EL CURSO TEMPORAL DE LA NEGACIÓN: · PDF fileEL CURSO TEMPORAL DE LA NEGACIÓN:...

EL CURSO TEMPORAL DE LA NEGACIÓN:

PROCESAMIENTO Y REPRESENTACIÓN

(The Temporal Course of Negation: Processing and Representation)

ISABEL ORENES CASANOVA

Director: Carlos Santamaría Moreno

Universidad de La Laguna.

Facultad de Psicología.

Departamento de Psicología Cognitiva, Social, y Organizacional.

Área de Psicología Cognitiva.

2 de Diciembre de 2013

3

D. Carlos Santamaría Moreno, Profesor Titular de la Universidad de La Laguna.

CERTIFICA que la presente Tesis Doctoral, realizada por Isabel Orenes Casanova con

el título “El curso temporal de la Negación: Procesamiento y Representación”, ha sido

elaborada bajo su dirección y supervisión en el Departamento de Psicología Cognitiva,

Social y Organizacional de la Universidad de La Laguna, y que dicha Tesis reúne, a su

juicio, los requisitos académicos y científicos necesarios para proceder a su presentación

y defensa pública ante el tribunal que se designe al efecto.

La Laguna, 29 de octubre de 2013

Fdo. Carlos Santamaría Moreno

5

Índice

‘*’ indicates that the chapter is written in English

Agradecimientos ............................................................................................................... 7

Prefacio: el puente entre el conocimiento y la realidad .................................................. 11

*General Abstract ........................................................................................................... 19

1. Negación: Concepto y Uso ........................................................................................ 27

2. Procesamiento de los enunciados negativos ............................................................... 31

2.1. Curso temporal de la negación: doble procesamiento ............................... 32

2.2. El tamaño del conjunto complementario ................................................... 36

2.3. La tarea de verificación: Integración de enunciados e imágenes .............. 39

3. Representación del operador negativo ........................................................................ 42

4. Estudiando la negación a través de los movimientos oculares ................................... 46

5. Objetivos ..................................................................................................................... 54

6*. How negation is understood: Evidence from the visual world paradigm ................ 57

6.1. Abstract ..................................................................................................... 57

6.2. Introduction ............................................................................................... 58

6.3. Experiment 1 ............................................................................................. 65

6.3.1. Method .......................................................................................... 66

6.3.2. Results ........................................................................................... 69

6.3.3. Discussion ..................................................................................... 75

6.4. Experiment 2 ............................................................................................. 76

6.4.1. Method .......................................................................................... 77

6.4.2. Results and Discussion ................................................................. 77

6.5. Experiment 3 ............................................................................................. 80

6.5.1. Method .......................................................................................... 82

6

6.5.2. Results and Discussion ................................................................. 83

6.6. General discussion ..................................................................................... 85

6.7. Conclusion ................................................................................................. 89

7*. Visual concepts impede negation ............................................................................. 91

7. 1. Abstract .................................................................................................... 91

7. 2. Introduction .............................................................................................. 91

7. 3. Experiment 1 ............................................................................................ 94

7.3.1. Method .......................................................................................... 94

7.3.2. Results and discussion .................................................................. 98

7. 4. Experiment 2 ............................................................................................ 99

7.4.1. Method ........................................................................................ 100

7.4.2. Results and discussion ................................................................ 101

7.5. General discussion ................................................................................... 103

8*. Inconsistencies make negation plausible: Evidence from the VWP ...................... 105

8.1. Abstract ................................................................................................... 105

8.2. Introduction ............................................................................................. 105

8.3. Method..................................................................................................... 109

8.4. Results ..................................................................................................... 112

8.5. General discussion ................................................................................... 120

9*. General Conclusion ................................................................................................ 123

References .................................................................................................................... 135

7

Agradecimientos

Me gustaría dedicar esta tesis a mis padres por confiar siempre en mí. También quisiera

agradecer al resto de mi familia, amigos y compañeros de trabajo por compartir

sonrisas, buenas conversaciones, sabrosas comidas y mensajes de ánimo para seguir

adelante en este proyecto.

Gracias también al Ministerio de Ciencia y Educación de España por otorgarme

una beca de formación del profesorado universitario (FPU) y a la fundación canaria

Manuel Morales, por becarme para seguir mi formación como investigadora durante el

año 2012. A la Universidad de La Laguna y sus profesionales por facilitar la ejecución

de este trabajo. A Alberto Avilés, Jon Andoni Duñabeitia, Manuel Gutiérrez, y

Christoph Scheepers por ayudarme con la técnica de movimientos oculares, técnica

principal de la tesis. A Phil Johnson-Laird, Sunny Khemlani, y Linda Moxey, con

quiénes tanto he aprendido sobre psicología cognitiva. A la Universidad de Glasgow,

donde he trabajado muchos meses. Y a los estudiantes de la facultad de psicología, que

muy amablemente participaron en los experimentos.

En especial, mi agradecimiento a Carlos Santamaría por su inteligencia,

conocimiento, y aportación en esta tesis así como su espíritu crítico que permite analizar

la realidad de forma alternativa.

Y a David Beltrán, GRACIAS por TODO.

9

A mis padres

Prefacio

11

Prefacio: el puente entre el conocimiento y la realidad

Me gustaría comenzar la tesis guiando al lector sobre lo que se va a encontrar en ella.

En este mismo primer apartado reflexionaré muy breve y libremente sobre un tema que

desde siempre me ha fascinado y que me ha llevado a adentrarme en el estudio del

pensamiento humano: la capacidad del ser humano para construir una sociedad como la

actual, de convertir piedras en instrumentos, sonidos en símbolos, y en definitiva, de

comprender y trasformar el mundo que le rodea, y esto sólo ha sido posible, a mi

entender, a través del conocimiento. Seguidamente, el lector entrará ya de lleno en lo

que constituye el tema de la presente tesis, la negación, encontrándose en primer lugar

con la introducción, en la que se plantea un marco teórico en relación a su

procesamiento y representación. A dicha introducción le seguirán los tres bloques de

estudios experimentales que suponen el núcleo principal del presente trabajo, los tres

escritos en inglés y en formato adecuado para su publicación. Y finalmente, la

conclusión general, donde se expondrá los principales resultados obtenidos en los

diferentes estudios experimentales así como sus principales aportaciones teóricas,

también escritas en inglés (igual que el Resumen de la tesis), por exigencias de la

modalidad de mención de doctorado internacional a la que se adscribe la presente tesis

doctoral.

Prefacio

12

Quisiera señalar que el concepto de mente es el punto oscuro que llegó a obsesionar a

los intelectuales de Occidente cuando al fin renunciaron a ese otro punto oscuro, el

concepto tecnológico de Dios. El carácter inefable de lo mental cumple la misma

función cultural que el carácter inefable de lo Divino: sugiere vagamente que la ciencia

no tiene la última palabra (Rorty, 1982).

Recuerdo que la primera vez que leí las palabras de Rorty me quedé atónita.

Tanto escepticismo te invita a reflexionar sobre el concepto de mente, que no es algo

banal ya que es el objeto de estudio de la psicología. Desde mi punto de vista siguen sin

estar claras preguntas básicas como: ¿existe realmente la mente?; si existe, ¿cómo

definirla?; y finalmente, la pregunta más importante para un investigador en el campo

de la psicología, ¿cómo estudiarla? Quizás fue Descartes el autor que distinguió más

claramente entre la mente y el cuerpo. Una idea mucho menos racionalista y más

romántica fue la que algunos defendieron al situar la mente en el corazón.

Probablemente hoy en día se concibe, fundamentalmente dentro de la Neurociencia

Cognitiva, y siguiendo la frenología y la concepción más empirista de Locke, que la

mente se reduce al cerebro.

Las neuronas son las responsables de procesar información en el cerebro. Son

unas células bastante peculiares ya que son las únicas que no se reproducen y tienen la

misma vida que el propio individuo. Mientras que la mayoría de las células se

regeneran, por otras que son capaces de realizar la misma función a través de la

información genética y la síntesis de aminoácidos, esto no ocurre para las neuronas. Lo

que diferencia a estas células del resto son las dendritas y los axones a través de los

cuáles se comunican usando señales electroquímicas. Y digo bien, señales

Prefacio

13

electroquímicas, porque toda la información que reciben nuestros sentidos, bien sea a

través de energía luminosa o química, es traducida al código electroquímico de las

neuronas. Ésta es la información que parece manejar el cerebro, por lo que uno se sigue

preguntando cómo estudiar la información, entendiendo ésta, ya no como código

eléctrico-químico, sino como conocimiento.

Cuando estudiamos los procesos cognitivos a través del cerebro, éste nos

informa sobre las partes que se activan, la actividad cerebral que produce o el

neurotransmisor implicado; sin embargo, en mi opinión, y espero que en la de otros

muchos también, esta información no explica la función cognitiva en sí, entendiendo

por explicación un principio que causaría dicha función cognitiva. Por ejemplo, la caída

de un cuerpo responde al principio que propuso Newton y está relacionado con la masa,

distancia y la constante de gravedad. El área de Broca parece que se activa con la

producción del lenguaje, pero su activación, por ejemplo con la técnica de estimulación

magnética (TMS), no podría producir directamente que una persona diga de manera

específica la palabra ‘hola’. Hoy por hoy sigue siendo más sencillo saludar a la persona

para obtener tal respuesta. Una cuestión menos complicada que la producción del

lenguaje, podría ser las causas de la ansiedad. Recuerdo estar en una clase de

psicofarmacología donde la profesora explicaba los mecanismos fisiológicos de la

ansiedad, pero la realidad es que es imposible descifrar si tal estado está provocado por

la boda o el despido de alguien, a menos que el propio sujeto informe de ello. Es

evidente que estos mecanismos neurofisiológicos solamente nos cuentan una parte de la

historia, para obtenerla completa se necesita algo más.

Recientemente, en un artículo científico publicado en Proceedings of the Royal

Society B: Biological Sciences, Susan Edwards y Stephen Pratt (2009) describían el

Prefacio

14

paralelismo que podría existir entre la conexión de neuronas y una colonia de hormigas.

Ambos conjuntos carecen de inteligencia de forma aislada, sin embargo, en conjunto

dan lugar a conductas inteligentes y conscientes. Desde este punto de vista, resulta

complicado localizar la mente en algún lugar del cerebro, más bien la mente surge o es

un potencial de la interacción de varias variables. Esta visión me recuerda a la

concepción que existe en física cuántica sobre los electrones, los cuales pueden estar en

varios sitios a la vez, pero ahí no acaba todo, parece que el lugar donde se encuentran

depende del observador. Esto sólo es posible si los electrones en vez de concebirlos

como materia se conciben como información. Si entendemos la mente como

información en este mismo sentido, yo me pregunto entonces si la mente puede estar en

varios sitios a la vez. Quizás sea algo parecido a la mente social que proponía Jung, y

sobre todo si la información depende del observador, y éste es nuestro objeto de estudio,

¿podría haber varias mentes posibles?

Concebir la mente como información es una influencia de la teoría de la

información y la computación. Algunos restringen la información a patrones de

activación como sería la teoría conexionista, pero, personalmente mi interés reside en

conocer cómo el ser humano es capaz de transformar la naturaleza en una sociedad, y

desde este punto de vista es necesario concebir la información como conocimiento.

Definición acertada o no, es una definición y probablemente el primer paso para

preguntarse cómo estudiarla: ¿cómo se adquiere el conocimiento? ¿Cómo se organiza y

representa? ¿Cómo se procesa y memoriza? ¿Qué información podría dar el cerebro

sobre el conocimiento? Etc.

En la presente tesis nos proponemos estudiar fundamentalmente los formatos de

representación del conocimiento, específicamente nos interesamos por la posibilidad de

Prefacio

15

que los individuos puedan representar la negación. Los niños a una edad muy temprana

(en torno al año) usan la negación cuando apenas tienen diez palabras en su vocabulario.

El primer vocabulario que producen suele estar relacionado con palabras esenciales con

un claro referente. Por ejemplo, es frecuente escucharles decir mamá, papá, tata, teta,

leche, agua. Es interesante descubrir o más bien darse cuenta que entre estas primeras

palabras se encuentra la negación, una palabra sin un claro referente, sin embargo su

función es fundamental porque se aplica a cualquier enunciado (proposición) y modifica

su significado (cambia su valor de verdad de falso a verdadero y viceversa). Además la

negación está presente en cualquier lenguaje, natural o artificial, lo que nos hace pensar

que su función es fundamental para nuestro desarrollo como humanos. Descubrir o

esclarecer cómo las personas comprendemos la negación es el objeto de estudio de esta

tesis, concretamente nosotros vamos a plantear fundamentalmente cómo nuestro sistema

cognitivo la procesa y representa.

17

El Curso Temporal de la Negación:

Procesamiento y Representación

(The Temporal Course of Negation: Processing and Representation)

General Abstract

19

General Abstract

Representation has been a central issue in cognitive science since the beginning (see

Bruner, Goodknow, & Austin, 1956). Nowadays, it is commonly accepted that iconic

(or analogical) representation is essential to language comprehension (Barsalou, 1999;

Glenberg, Meyer, & Lindem, 1987; Johnson-Laird, 1983; Zwaan & Radvansky, 1998).

This means that individuals understand language by representing an analogical structure

in their mind that corresponds to the structure of the world being described. However,

there are some components of natural language, such as negation, that do not have any

analogical correspondence in the real world. Following Wittgenstein’s classical example

(1953), one could well employ an image of a red figure with a superimposed cross to

represent the sentence ‘The figure is not red’, but one would have still to know that the

cross symbolizes negation, and nothing in the image could tell us that. Furthermore, one

would have to know what negation itself means.

Negation is a syntactic operator that takes an argument (e.g., Spain won the

Confederations Cup final in 2013) and reverses its truth value. This means that if an

argument is false, then its negation is true (e.g., Spain did not win the 2013

Confederations Cup) and vice versa. This meaning can only be captured symbolically.

However, embodiment theory, one of the frameworks that has risen to dominance in

cognitive science today, holds that negation is only understood iconically. The main

contribution to knowledge of the present thesis is the finding that individuals are able to

understand negation symbolically. Although previous studies have shown this using

reaction time (Clack & Chase, 1972), we present evidence of the unfolding processing

of this kind of representation using the tracking of eye movements. The assumption is

General Abstract

20

that there is a direct relation between what the eyes look at and what the mind

processes.

Other contributions of the present thesis relate to how the comprehension of

negation is modulated by the representation of the negated argument and the context in

which it occurs. The meaning of negation is difficult for most individuals to understand,

leading to longer processing times and higher error rates compared to the corresponding

affirmation. A variety of factors have been proposed to account for this fact, ranging

from purely grammatical mechanisms to the influence of affective connotations. But

accounts based on semantic and pragmatic factors are surely the most supported by

empirical evidence (Miller, 1962; Wason, 1965).

Semantic accounts attempt to answer the question of how the meaning of a

negative sentence is understood by a representational mind. As a result, they explain the

differences between negation and affirmation on the basis of mental processes and

representations. A considerable part of this dissertation is dedicated to delving further

into these types of cognitive explanations of how negation is understood. First, we make

use of a new methodology, the visual world paradigm, to reconcile two well-established

cognitive theories: embodiment and mental model theory. Second, we offer a new

perspective of the semantic function of negation and examine its impact on the

comprehension of concepts that vary in their degree of concreteness.

Pragmatic accounts confront the issue of negation complexity from a different

perspective. They focus on providing an answer to the questions of why and how people

use negation in a communicative context, and consider that comprehension is

definitively influenced by how much appropriate (felicitous) information is being used

in a given context (Givon, 1978; Wilson & Sperber, 2004). The main pragmatic account

General Abstract

21

(the denial hypothesis) claims that negation is used to deny what a hearer might be

mistakenly keeping in mind. In the third part of this dissertation, the role of denial in

comprehension is evaluated, again by means of the visual world paradigm methodology.

The following is a summary of the different experiments run to study the three

main predictions comprising the experimental part of this dissertation.

1. How negation is understood: Evidence from the visual world paradigm.

As explained above, the first goal of the present dissertation was to show that

individuals are able to understand negation symbolically. To test this, we studied the

process of understanding negation and the resulting mental representations. The two-

step theory (Kaup, Lüdtke, & Zwaan, 2006), based on the embodiment theory, holds

that the understanding of a negative sentence, like the figure was not red, leads to the

construction of two iconic mental representations: first, the negated situation (e.g., a red

figure) and next, the actual situation (e.g., a green figure). Remarkably, this theory

claims that the two representational steps are compulsory, in that they must occur

whenever the comprehension of a negative sentence is at stake. In this way, the

inclusion of symbolic operations is avoided.

Alternatively, the mental model theory, while accepting that individuals will

represent the actual situation to understand negation whenever possible, also holds that

they can represent the negated situation and apply a symbol for negation. Hence, this

theory recognizes two ways of dealing with negation, as well as the possibility of

including symbolic operations in its comprehension (Khemlani, Orenes, & Johnson-

Laird, 2012).

Our hypothesis was that the comprehension of negative sentences is modulated

by the availability of the actual situation. In our experiment, this actual situation was

General Abstract

22

made available in what we called the binary context, in which a disjunctive sentence

like the figure could be red or green appeared before a negative sentence like the figure

was not red. But it was unavailable, in the sense of underspecified (or indefinite), in

what we called the multary context, wherein the same negative sentence followed a

sentence like the figure could be red, or green, or blue, or yellow. Also, we made use of

the visual world paradigm methodology, which allowed us to track semi-continuously

participants’ visual attention over a set of four figures shown in the screen, while they

were hearing the passages containing both the context (binary or multary) and the target

sentence (affirmative or negative).

For the binary context, the same outcome was predicted by both the two-step

and the mental model theories: that there would be an initial focus of attention on the

figure representing the negated situation (a red figure) followed by a focus on the figure

representing the actual situation (a green figure). In contrast, different predictions were

anticipated for the multary context: under the mental model theory, the prediction was

that there would be persistent attention on the figure representing the negated situation,

while the two-step theory predicts a progressive decrease of attention on that figure.

In Experiment 1, we confirmed predictions of the mental model theory and

found that people shifted their visual attention toward the figure representing the actual

situation in the binary context, while focusing exclusively on the negated figure in the

multary context. This latter finding, the focus of attention on the negated figure, was

confirmed using different tasks in two follow-up experiments (Experiment 2:

recognition; Experiment 3: verification) in which negative sentences were presented

without any preceding context. The finding of a persistent focus on the negated figure

suggests that the comprehension process was relying on the representation of the

General Abstract

23

negated situation, and hence that the actual situation is of no use for understanding

negation outside of a binary context.

Thus, these findings pose a problem for the two-step theory. They show that the

two simulation steps are not necessary to understand negation. Instead, they tend to

support the mental model theory, which claims that negation can be understood by

keeping the negated situation plus a symbolic tag indicating that this situation is

negated.

2. Visual concepts impede negation. The second goal of the present

dissertation was to demonstrate that an argument that is symbolic could make negation

easier to understand. We predicted that the negation of arguments that involve visual

words (related to the representation of an image) would be slower to process than

negation involving non-visual words (although visual words are ordinarily easier to

process). To test this hypothesis, we carried out two experiments.

In Experiment 1, we presented a context that alternated between negation of the

argument involving the visual (iconic) word: the boy was brave and he was not asleep

and negation of the non-visual (or symbolic) argument: the boy was awake and he was

not cowardly. The next sentence (the target) consisted of a similar conjunctive phrase

with the same meaning, but with the previously negated word replaced by its contrary

visual argument (e.g., the boy was brave and he was awake). The target sentence was

similar for both conditions, and we measured the time that people took to read this

target. As predicted, results showed that participants took longer to read the target

sentence after the negation of the visual argument than after negation of the non-visual

argument, although visual concepts had been found to be easier to comprehend than

non-visual concepts in a previous lexical decision task.

General Abstract

24

In Experiment 2, we corroborated the previous result using a similar design. In

this case, we presented a context that alternated between negation of the argument

involving visual word (e.g., the boy was brave and he was not asleep) and negation of

the non-visual word. The next sentence (the target) consisted of a similar conjunctive

phrase, but without negation (e.g., the boy was brave and he was asleep). This was done

to test that the effect found in Experiment 1 was due to the type of representation of the

negated word (e.g., asleep), rather than its cancellation. Together, these two experiments

lead to the conclusion that iconic representation could impede some symbolic

operations such as negation.

3. Inconsistencies make negation plausible: Evidence from the visual world

paradigm. The third goal of the present dissertation was to prove whether the context in

which the argument is presented could make negation predictable and easier to

understand. A special case of this prediction occurs when the negation functions to deny

a misconception. Outside of this context, negation is more difficult to understand than

affirmation (Givon, 1978).

To test this hypothesis, we presented three types of context followed by

affirmative or negative sentences (e.g., her dad was (not) poor) while presenting images

of the affirmed (e.g., a poor man) or denied entities (e.g., a rich man). In a neutral

context (e.g., her dad lived on the other side of town) the participants looked at the

affirmed entities before the denied entities. This effect was magnified when the context

corresponded to a contextually true belief, that is, when the context and the target

sentence were consistent (e.g., She supposed that her dad had enough savings followed

by her dad was not poor). However, people looked at the object that corresponded to

the negation within the same time frame as they looked at the object that corresponded

General Abstract

25

to the affirmation when the sentence referred to a contextually false belief, that is, when

the context and the target sentence were inconsistent (e.g., She supposed that her dad

had little savings followed by her dad was not poor). Those results corroborated our

prediction. Negation was as easy to comprehend as affirmation when it was used to

deny a false belief (or misconception). Outside of this context, negation was more

difficult to understand than affirmation.

The findings of this section confirmed denial hypothesis predictions, leading to

the conclusion that there is an asymmetry in the usage of the main semantic function of

negation (truth-value reversal) that modulates comprehension. In particular, they

indicate a preference of using negation to reverse the value of mistakenly held ideas. It

is likely that this asymmetry in use is related to the important maxim in communication

of telling the truth.

Conclusions. The empirical analysis addressed in this dissertation has yielded

three main findings with important consequences not only for the topic of negation, but

also for the more general topic of language comprehension.

As a whole, these findings lead us to conclude that the comprehension of

negative sentence is modulated by the core semantic meaning of negation (truth-value

reversal). This meaning can be only represented symbolically, from whence follows that

any representational theory of human language has to consider including symbolic

representation for connective concepts like negation. Our results fit better with the

mental model theory than with the two-step theory. Also, we have revealed for the first

time that iconic (visual) representations slow the comprehension of negative sentences.

This finding could be generalized to reasoning and would indicate that symbolic

representation could be essential in certain complex tasks. This type of representation

General Abstract

26

allows for ease of operation, because it reduces the processing load on working

memory. And finally, we have shown that although negation is more difficult to

understand than affirmation, the meaning of negation is easily understood when it is

used in a denial context.

Procesamiento y Representación de la Negación

27

1. Negación: Concepto y Uso

Desde Aristóteles, la negación -expresada generalmente en castellano con la palabra no-

se define como un operador sintáctico que se aplica sobre un argumento (palabra o

frase) y revierte su valor de verdad, de falso a verdadero y viceversa (ver Aristotle,

1984). En términos lógicos un enunciado y su negativo se contradicen el uno al otro, es

decir, si uno es verdadero, el otro es necesariamente falso. Por ejemplo, si la frase

afirmativa ‘Jefferson inventó el pararrayos’ es falsa entonces su correspondiente

negativa ‘Jefferson no inventó el pararrayos’ debe ser necesariamente verdadera. Fíjese

el lector que la negación se usa para señalar que un argumento es falso: ‘Es falso que

Jefferson inventó el pararrayos’.

La función de la negación quizás sea falsar enunciados, pero la negación y la

falsedad son dos términos diferentes. Primero, porque un enunciado negativo (por ej.,

No estoy en España) puede ser tanto verdadero como falso y, paralelamente, un

enunciado falso (por ej., Es falso que estoy en España) podría expresarse tanto en modo

afirmativo como negativo (por ej., Es falso que no estoy en España). Y segundo, porque

la negación es parte del lenguaje, un elemento sintáctico del mismo con consecuencias

semánticas, mientras que la falsedad es un aspecto del metalenguaje, es decir, no es

expresado en el lenguaje en sí sino más bien dice algo sobre éste (ver Khemlani,

Orenes, & Johnson-Laird, 2012).

Con respecto al uso o función de la negación, una idea bien establecida es que

no tiene ningún sentido negar un enunciado a menos que exista alguna razón para creer

que lo afirmado por dicho enunciado es falso (véase por ejemplo, Horn, 1989). Según

esta idea, la única razón para que alguien dijese que ‘Jefferson no inventó el pararrayos’


28

es que previamente se hubiese afirmado, o bien se aceptase más o menos implícitamente

como verdadero que ‘Jefferson inventó el pararrayos’. De no ser así, seguramente el

hablante habría utilizado directamente la frase afirmativa verdadera: ‘Franklin inventó

el pararrayos’ – por supuesto, siempre y cuando estuviese en posesión de dicho

conocimiento. Por tanto, el uso de la negación tiene como función principal falsar un

mensaje, o en un sentido más amplio corregir la idea de un hablante (Givon, 1978;

Strawson, 1952; Wason, 1965).

La función correctora de la negación sugiere que el hablante hace uso de ella

para corregir la opinión de un interlocutor, posiblemente con la esperanza de que éste

acabe rechazándola y abandonándola. No obstante, dicho distanciamiento quizás no se

produzca, y no tanto por culpa del apego que el interlocutor le tenga a su propia opinión,

como por la importancia que ésta adquiere al caer dentro del foco de la negación. Negar

una idea significa dotarla de cierto protagonismo en el ejercicio de la comprensión. Si o

no ello conduce al rechazo y consecuente olvido de dicha idea depende de factores que

en ocasiones pueden pasar inadvertidos para el hablante. Así, si se dice a alguien que ha

sufrido un accidente ‘No pienses en el accidente’, lo más probable es que su

pensamiento acabe precisamente centrado en el accidente, por más que nuestro objetivo

no fuese precisamente ese. Por tanto, parece poco eficaz el uso de la negación cuando el

objetivo es promover el abandono por parte del interlocutor de una idea o conducta.

Aunque, como bien indicó Freud (1925), el hecho de que alguien niegue una idea de

manera repentina e inesperada quizás deba tomarse precisamente como indicio de

aquello entorno a lo que realmente giran sus preocupaciones. En lugar de sustituirla por

otra más apropiada, Freud recomienda al psicoanalista centrar el análisis sobre lo que


29

está siendo negado. De ahí, ya emergerá por asociación lo que bulle en su

subconsciente.

El estudio del desarrollo del lenguaje deja bien claro que existen varios usos

diferentes de la negación, no solamente el que lo vincula a una función correctora

(Horn, 1989). Por ejemplo, cuando los niños empiezan a utilizar la palabra no la usan

para indicar que un objeto ha desaparecido: ‘No está’, y también se utiliza

tempranamente para oponerse o rechazar algo. Como cuando la madre le dice ‘Vamos a

dormir’ o ‘Ponte la camiseta roja’ y el niño le responde que ‘No’. En este sentido, el

niño trata de comunicar que no está de acuerdo con lo que dice la madre o no está

motivado para hacerlo. Además los niños están familiarizados con la negación porque

los adultos la utilizan para prohibir, ‘No metas los dedos en el enchufe’ o ‘No cruces la

carretera solo’ (Morris & Hasson, 2010). Por tanto, la negación puede ser usada con

otros objetivos como la comunicación de no-existencia, rechazo o prohibición. De

hecho, la función de falsar, su principal uso, es la última que se adquiere en el desarrollo

cognitivo (para una revisión, Horn, 1989).

Hasta ahora hemos visto ejemplos en los que la negación se aplica sobre todo el

enunciado. Actualmente sigue abierto sin embargo el debate sobre si la negación podría

aplicarse a un argumento menor que la proposición en su conjunto (Khemlani y cols.,

2012). La realidad es que la negación se puede aplicar a diferentes partes del enunciado.

Por ejemplo, en el verbo o en el adjetivo. En relación a este último ejemplo, es relevante

el caso de los adjetivos marcados. Un adjetivo marcado es aquel que contiene una

negación implícita (Clark, 1969; 1974). Por ejemplo, el adjetivo ‘ausente’ es marcado

porque contiene la negación ‘no presente’. El uso de los adjetivos marcados es de

interés porque su uso no es necesario, es decir, éstos pueden ser expresados a través de


30

la negación (por ejemplo, no encendido-apagado; no grande-pequeño; no alto-bajo; no

rico-pobre), sin embargo las personas prefieren utilizar otra palabra, y no incluir

directamente la negación. Hay algunos conceptos contrarios que se han formado

sustituyendo el operador negado no por un prefijo: im-, des-, in-, di-, etc. Lo relevante

es que las palabras y sus contrarios suelen estar muy asociadas, es decir, unas evocan a

otras y viceversa (Fernández y cols., 2004). Este hecho es importante en el

procesamiento de la negación porque permite sustituir la negación por su contrario, y

como veremos más adelante, un enunciado afirmativo se procesa y memoriza mejor que

un enunciado negativo. Ahora bien, no siempre una negación puede ser sustituida por su

contrario. Por ejemplo, cuando se escucha en los medios de comunicación que ‘los

funcionarios no son ricos’, rara vez se entiende que ‘ellos son pobres’, más bien se

entiende que ellos no son ni pobres ni ricos sino que pertenecen a la clase media. Este

ejemplo nos indicaría que la negación tiene la función de modificar o mitigar, no

siempre contradecir, el argumento sobre el que se aplica. Este sería el caso de adjetivos

como caliente y frío. Si uno pide un café en el bar y dice ‘el café no está caliente’ no

significa que está frío, más bien que no está todo lo caliente que le gustaría o que está

templado. La negación en el lenguaje natural, además de contradecir, modifica el

argumento sobre el que se aplica en un sentido más amplio y variado, el cuál dependerá

en muchos casos de la pragmática de la comunicación (Giora, 2006; Schul, 2011).


31

2. Procesamiento de los enunciados negativos

La negación ha sido tradicionalmente estudiada en lingüística y filosofía (ver Horn,

1989). Sin embargo, a partir de los años 60 y 70 los psicólogos empezaron a interesarse

por cuál podría ser el efecto del operador negativo sobre el procesamiento cognitivo.

Los resultados han mostrado de forma consistente que los enunciados negativos son

más difíciles, producen mayor tiempo de reacción y mayor número de errores que los

enunciados afirmativos (Wason, 1959, 1961).

En un primer momento se interpretó que el mayor tiempo en la lectura de un

enunciado negativo podría deberse a la presencia de una sílaba extra, pero el tiempo que

se estima para leer una sílaba es de 25-90 ms mientras que el efecto de la negación es de

más de 100 ms (Clark & Chase, 1972). También se ha destacado que la dificultad de la

negación podría deberse a que ha sido asociada con connotaciones negativas (por ej.,

prohibiciones; Wason & Jones, 1963). En este sentido, Eifermann (1961) realizó un

experimento en hebreo, en cuya lengua existe dos palabras para el no: lo que se usa para

prohibir y eyno que se usa como negación. Los resultados mostraron tiempos de lectura

más largos y más errores asociados con lo que con eyno. Este experimento iría además

en contra de aquellos que consideran que la dificultad de la negación es debida a su

poca frecuencia ya que lo es más frecuente en el lenguaje hebreo que eyno. Otra posible

explicación ha sido que la negación requiere de un mayor número de trasformaciones

gramaticales comparado con los enunciados afirmativos (Klima, 1964). Aunque Miller

(1962) mostró que factores semánticos, y no sintácticos, son los responsables de la

complejidad de la negación, al encontrar que las diferencias entre los enunciados

afirmativos y negativos se reducían cuando eran oraciones pasivas frente a activas.


32

A pesar de las numerosas interpretaciones que han tratado de explicar por qué

los enunciados negativos resultan más difíciles que sus correspondientes enunciados

afirmativos, probablemente la que más peso ha tenido en la literatura, y la que se

detallará en el siguiente apartado, ha sido que para comprender enunciados negativos se

requiere de un doble procesamiento que no es necesario para la afirmación. Esta idea

viene del lógico Bertrand Russell quien escribió que ‘cuando digo “esto no es azul” de

alguna manera considero que es azul primeramente y después lo rechazo, considerando

un color diferente al azul’ (Russell, 1948).

2.1. Curso temporal de la negación: doble procesamiento

Siguiendo las propias palabras de Russell se podría considerar que para la comprensión

de enunciados negativos, tales como ‘la puerta no está abierta’, primero se procesa el

argumento negado, abierta, y después se aplica el operador negativo no sobre dicho

argumento para inferir su conjunto complementario, cerrada. Esta inferencia requiere de

tiempo adicional comparado con su correspondiente enunciado afirmativo, ‘la puerta

está abierta’, cuya comprensión no requiere de ninguna inferencia, y de ahí su menor

dificultad. Recientemente, Kaup, Lüdtke y Zwaan (2006) corroboraron esta idea a través

de una tarea de naming. Los autores presentaron enunciados negativos con predicados

contrarios (por ej., La puerta no está abierta) y después de 750 o 1500 ms presentaron

una imagen que correspondía (por ej., una puerta cerrada) o no con el enunciado (por

ej., una puerta abierta). La tarea de los sujetos era nombrar el objeto de la imagen, en

ambos casos ‘puerta’. Encontraron que a los 750 ms, los sujetos nombraban más rápido

‘puerta’ cuando veían una puerta abierta que una cerrada, mientras que los resultados


33

eran opuestos cuando el intervalo entre enunciado y figura fue de 1500 ms. En este caso

nombraban más rápido ‘puerta’ cuando ésta era una puerta cerrada que cuando era

abierta. Estos resultados parecían confirmar que los individuos representan primero el

argumento negado (por ej., abierta) y después el conjunto complementario (por ej., una

puerta cerrada). Además, demuestran también que tal inferencia podría darse entre los

750 y 1500 ms, con lo cual la comprensión de la negación podría ser tardía.

Moxey y Sanford (1987) también mostraron que para la comprensión de ciertos

cuantificadores era requerido el doble procesamiento. Por ejemplo, los autores

encontraron que los individuos después de leer ‘Unos pocos de los fans fueron al

partido’ inferían ‘Ellos gritaron en el campo’, mientras que cuando leían ‘Pocos fans

fueron al partido’ inferían ‘Ellos se quedaron en casa’. Esto es, el cuantificador ‘unos

pocos’ hace referencia a los que van a ver el partido mientras que ‘pocos’ es un

cuantificador negativo que hace referencia al conjunto complementario, es decir, a los

que no van a ver el partido. En este sentido, el uso de estos cuantificadores sería el

mismo que el de la negación. Tal y como se ha planteado antes, sólo si alguien piensa

que ‘Jefferson inventó el pararrayos’, se diría que ‘Jefferson no inventó el pararrayos’.

De la misma manera sólo en el caso de que alguien pensara que se iba a llenar el campo

entonces se podría decir que ‘Pocos fans fueron al partido’.

Igualmente, se ha encontrado que en la comprensión de condicionales

contrafactuales (por ej., Si los deportistas hubieran ganado el partido entonces ellos

hubieran tenido unas vacaciones) y también de aquellos enunciados que expresan

deseos (por ej., A los deportistas les gustaría ganar el partido) se procesan tanto la

situación que se describe como su complementaria (ver Byrne, 2005). Esto es, se

produce un doble procesamiento similar al antes visto para la negación y los


34

cuantificadores. Aunque, recientemente Nieuwland y Martin (2011) han obtenido

resultados contrarios que parecen indicar que no es necesario el doble procesamiento

para su comprensión.

La necesidad de un doble procesamiento también ha sido puesta en duda para la

negación recientemente. Por ejemplo, Nieuwland y Kuperberg (2008) presentaron una

tarea de lectura usando la técnica de potenciales evocados, con la peculiaridad de que

los enunciados afirmativos y negativos eran plausibles (por ejemplo, ‘Viajar a Bagdad

no es seguro por la guerra’ podría ser similar a ‘Viajar a Bagdad es peligroso por la

guerra’ según indicaron los participantes en un estudio normativo, es decir, ambos

enunciados eran considerados igualmente plausibles). Los autores encontraron efectos

principales de verdad en un componente cerebral relacionado con la integración

semántica (N400). Es decir, encontraron que los enunciados falsos presentaban mayor

N400 que los enunciados verdaderos con independencia de la polaridad, esto es, de si

eran afirmativos o negativos. Este efecto principal de verdad solamente es posible

encontrarlo si la interpretación de la negación ya está disponible en el momento que se

lee la palabra clave, lo que sugiere que la negación está siendo integrada

inmediatamente en el proceso de comprensión. Tan rápida integración de la negación no

es congruente, sin embargo, con el doble procesamiento, el cual según han indicado

algunos estudios requeriría de entre 750 a 1500 ms (Kaup y cols., 2006). Tian, Breheny,

y Ferguson (2010) encontraron también efectos tempranos de negación utilizando una

tarea diferente. En este caso, se presentaron dos tipos de enunciados negativos: hendidos

(por ej., Fue Jane quien no cocinó espagueti) y no hendidos (por ej., Jane no cocinó

espagueti) y 250 ms después, aparecía una imagen que correspondía (por ej., Un plato

de espagueti sin hacer) o no (por ej., Un plato de espagueti hecho) con el enunciado. La


35

tarea de los sujetos era indicar si el objeto de la imagen había sido nombrado. Los

resultados mostraron interacción entre el tipo de enunciado y la correspondencia (o no)

entre enunciado e imagen. Es decir, en el caso de los enunciados no hendidos, las

respuestas eran más rápidas cuando la imagen no correspondía que cuando

correspondía, lo que confirma el doble procesamiento de la negación. En cambio, para

los enunciados hendidos los resultados fueron opuestos, lo que indicaría que a los 250

ms, la negación había sido comprendida. Una vez más, estos resultados indicarían que

la comprensión de la negación es temprana bajo ciertas situaciones, y que posiblemente

el doble procesamiento o bien se realiza rápidamente o bien no es necesario.

Algunos autores han señalado que estos efectos tempranos de la negación se

deben a la influencia de la pragmática (por ej., Dale & Duran, 2011; Nieuwland &

Kuperberg, 2008; Tian y cols., 2010). Nosotros estamos de acuerdo con esta postura, es

decir, el papel de la pragmática es facilitar la comprensión de la negación al igual que

facilita el procesamiento en general. Ahora bien, ésta no puede explicar por qué los

enunciados negativos son más difíciles que los afirmativos cuando se presentan sin

contexto, en todo caso la pragmática podría explicar la facilitación de la negación

comparado con la afirmación en contextos favorables. Nuestra postura es sin embargo

que tal dificultad, la que es indicada por las diferencias entre afirmativas y negativas,

se debe a factores semánticos (Miller, 1962). No hay ningún caso en el cual un

enunciado afirmativo (por ej., Es rojo) y su negativo (por ej., No es rojo) sean

semánticamente idénticos, ya que el operador negativo aumenta el significado del

argumento sobre el que se aplica. Ahora bien, la frecuencia de uso o un contexto que

anticipe el concepto negado podría facilitarla, como veremos en el siguiente apartado, y


36

hacerla más parecida a su homóloga afirmativa en lo que a coste de procesamiento se

refiere.

2.2. El tamaño del conjunto complementario

Es frecuente encontrar expresiones en el lenguaje que requieren de la realización de

inferencias para su comprensión (Johnson-Laird, 1983). Por ejemplo, en el caso de las

anáforas, tal como ‘María se va a ir de viaje y ella se está preparando la maleta’ se

tendría que inferir que ella se refiere a María para su comprensión. Dicha inferencia

puede complicarse si nos dicen que ‘María se va a ir de viaje con Amalia y ella se está

preparando la maleta’ En este caso sería difícil saber si ella se refiere a María o a

Amalia. Esta ambigüedad es frecuente en los enunciados negativos cuando el conjunto

complementario se refiere a varias posibilidades (Condición Múltiple). Por ejemplo,

para comprender el enunciado negativo ‘La puerta no es azul’ los individuos podrían

inferir que el conjunto complementario de azul podría hacer referencia a marrón, verde,

roja, amarilla, etc.

Listar este conjunto de posibilidades llevaría mucho tiempo para su

procesamiento, además de suponer una sobrecarga para la memoria. Debido a que la

memoria de trabajo es limitada, resulta predecible que los individuos tiendan a

representar el menor número posible de posibilidades, para lo que en determinadas

situaciones pueden verse ayudados por el contexto, el cuál puede ayudar a desambiguar

y por tanto conducir a una reducción en el número de posibilidades (Khemlani y cols.,

2012). No obstante, otra forma, quizás más eficiente, de reducir el número de

posibilidades sería que los individuos no realicen tal inferencia y mantengan el operador


37

negativo en memoria, es decir, en estos casos los individuos comprenderían, por

ejemplo, ‘La puerta no es azul’ manteniendo el argumento negado, y de esta manera

reducirían tiempo y memoria para su procesamiento (Giora, 2006). Es más, en este caso

seguiría resultando más difícil la negación que su correspondiente afirmativa porque

aunque no requiera de una inferencia (o doble procesamiento) es, como ya hemos dicho,

semánticamente más compleja. De la misma manera, las personas podrían comprender

el siguiente enunciado: ‘Ella se está preparando la maleta’ sin necesidad de saber quién

es ella.

Estos ejemplos nos llevan a concluir que hay diferentes grados de comprensión

de un enunciado negativo, más o menos específico, dependiendo de la accesibilidad de

su complementario. Así, en el caso de la negación es posible comprender ‘La puerta no

es azul’ como la puerta no es azul o la puerta es amarilla (u otro color), dependiendo de

la información disponible. Esta propiedad o característica no está presente para las

afirmativas, las cuales suelen tener un significado más específico. Glenberg y

colaboradores (1999) encontraron que los enunciados afirmativos y negativos (por ej.,

El abrigo (no) era negro) podrían ser procesados igual cuando previamente presentaban

una situación plausible, tal como, ‘Ella no estaba segura si el mejor abrigo podría ser

claro u oscuro’. Mientras que, por el contrario, los enunciados negativos eran más

difíciles que los afirmativos después de leer un contexto no plausible ‘Ella no estaba

segura de qué tipo de material sería el abrigo’. Los autores consideraron que un

contexto plausible era aquel que presentaba la misma temática que la frase crítica, en

este caso el color. No obstante, dicho contexto fue presentado en este experimento de

forma binaria (claro u oscuro), y aunque los autores no atienden a este hecho

explícitamente, la realidad es que este contexto binario reduce el número de


38

posibilidades, y convierte a la negación en específica, al igual que la afirmación. Por

tanto, podríamos concluir que la comprensión de la negación se ve beneficiada cuando

los individuos pueden convertir la negación en una afirmación.

Probablemente fue Wason (1961) el primer psicólogo en descubrir que los

individuos convertían los enunciados negativos binarios, esto es, aquellos que tienen

una alternativa accesible, por ejemplo ‘El 9 no es par’ era sustituido por ‘El 9 es impar’

antes de decidir si un enunciado era verdadero o falso. Watson (1979) presentó

imágenes con alguna diferencia entre ellas a niños de entre 7 y 9 años, y encontró que

los infantes utilizaban la negación (66%) para expresar ausencia o pérdida de una

imagen con respecto a otra, por ejemplo, ‘El caballo no tiene cola’ o ‘El caballo no tiene

las riendas’; mientras que ellos preferían utilizar la alternativa afirmativa cuando había

una o varias posibilidades, por ejemplo, el tamaño (por ej., ‘Es grande’ frente a la otra

imagen en la que aparecía un objeto pequeño). Este mismo resultado fue encontrado en

Beltrán, Orenes, y Santamaría (2008), donde también se presenta una tarea de

producción pero en este caso con adultos. Además se encontró que los participantes

preferían utilizar más la negación para la condición múltiple, la cual no tenía un

conjunto complementario específico, que para la binaria. Estos estudios parecen

demostrar que los individuos a veces, sobre todo cuando el conjunto complementario es

específico (condición binaria), tienden a inferirlo, lo que confirmaría el doble

procesamiento para la comprensión de la negación; sin embargo, cuando el conjunto

complementario no es específico (condición múltiple), es posible que los individuos no

hagan ninguna inferencia y mantengan la negación a menos que el contexto indique de

alguna u otra manera cuál es la situación verdadera específica.


39

2.3. La tarea de verificación: Integración de enunciados e imágenes

Una de las tareas más frecuentemente usadas para el estudio de la negación ha sido la

verificación frase-imagen. En ella, los participantes tienen que indicar si un enunciado

(afirmativo o negativo) es verdadero o falso con respecto a una imagen. Clark y Chase

(1972) entendían que para realizar con éxito esta tarea, los participantes deberían

comparar el enunciado con la imagen en el mismo formato de representación. En el caso

de que ambas representaciones coincidiesen, la respuesta se consideraba verdadera;

mientras que cuando ambas representaciones no son similares, entonces la respuesta

sería falsa. Uno de los resultados más consistentes que se ha obtenido con la tarea de

verificación ha sido la interacción entre el valor de verdad y la polaridad (ver

Carpenter & Just, 1975; Clark & Chase, 1972; Trabasso, Rollins, & Shaughnessy, 1971;

Wason & Johnson-Laird, 1972; Wason & Jones, 1963). Esto es, los enunciados

afirmativos verdaderos son más fáciles que los enunciados afirmativos falsos ya que

mientras que hay una correspondencia o matching entre los enunciados afirmativos

verdaderos (por ej., A está encima de B) y la imagen (por ej., A/B); no hay tal

correspondencia (o se produce un mismatching) entre los enunciados afirmativos falsos

(por ej., B está encima de A) y la imagen (por ej., A/B). El caso opuesto ocurre para los

enunciados negativos, es decir, los enunciados negativos falsos son más fáciles que los

negativos verdaderos por la correspondencia frente a la no correspondencia o

mismatching entre el enunciado y la imagen.

Lüdtke y colaboradores (2008) presentaron una tarea de verificación usando

potenciales evocados. Los autores presentaron enunciados afirmativos y negativos (por

ej., En frente de la casa (no) hay un gato) y después aparecía una imagen que


40

correspondía o no con el enunciado. Ellos manipularon el tiempo de presentación entre

los enunciados y la imagen. En la mitad de los ensayos la imagen aparecía a los 250 ms

y en la otra mitad a los 1500 ms. Los resultados mostraron la clásica interacción entre el

valor de verdad y la polaridad cuando la imagen aparecía 250 ms después del

enunciado. Estos datos indicarían correspondencia o matching entre el enunciado y la

imagen, que sería más fácil que la no correspondencia. Sin embargo, cuando analizaron

la imagen presentada 1500 ms después del enunciado entonces aparecían efectos de

negación, por lo que los autores concluyeron que la negación podría ser comprendida en

periodos tardíos. Una pregunta que surge es si los efectos encontrados en este estudio

están relacionados con la propia comprensión o más bien con la verificación. Es decir,

una vez que los individuos han comprendido el enunciado, al ver la imagen, tienen que

contrastar o comparar el enunciado con la imagen y decidir si el enunciado es verdadero

o falso con respecto a la imagen, y este proceso requiere de tiempo, especialmente para

la negación ya que no hay ninguna imagen que corresponda directamente con un

enunciado negativo. El caso que podría resultar más sencillo es cuando el enunciado

negativo es falso, ya que si después de leer ‘Enfrente de la casa no hay un gato’ aparece

un dibujo con un gato enfrente de una casa es relativamente sencillo identificar que es

falso. Ahora bien, cuando leían el enunciado negativo ‘Enfrente de la casa no hay un

gato’ y aparecía un gato arriba de la casa, en principio, tendrían que indicar que el

enunciado es verdadero, pero es igual de verdadero que si aparece abajo, detrás o dentro

de la casa. Ante tantas posibilidades verdaderas, los participantes en la tarea debieron

aprender que el gato podría aparecer enfrente o arriba de la casa (condición binaria), por

tanto una estrategia que podría facilitar la tarea sería convertir el modelo negativo (por

ej., Enfrente de la casa no hay un gato) en un modelo alternativo afirmativo (por ej.,


41

Arriba de la casa hay un gato) que pudiera comparar con la imagen directamente, y esta

inferencia podría requerir de tiempo, según los autores hasta 1500 ms. La pregunta

teórica clave es si dicha inferencia que parece útil para la tarea de verificación es

necesaria para la comprensión del enunciado. Para responder a esta pregunta se va a

presentar primeramente una tarea neutra como puede ser el reconocimiento más que una

de verificación, la cual podría facilitar, como hemos indicado previamente, la

conversión de un modelo negativo a uno afirmativo.

Fueron Young y Chase (1971) los que anticiparon que ciertas tareas o

instrucciones podrían facilitar la conversión de los enunciados negativos a afirmativos y

además mostraron que la conversión requiere de tiempo, lo que podría confirmar que tal

proceso se realice entre los 750 y 1500 ms. En nuestra opinión, y atendiendo a los

estudios analizados, todas aquellas tareas en las que se requiere integrar enunciados

negativos con una imagen van a facilitar su conversión para mejorar la comparación.

Esto es lo que ocurriría en la tarea de verificación frase-imagen; pero también en tareas

que sin requerirlo en algún nivel se integran ambas, y esto podría ocurrir en la tarea de

naming de Kaup y colaboradores (2006) cuya tarea solamente era nombrar el objeto de

la imagen, pero tal tarea se hacía más rápida cuando el objeto de la imagen correspondía

con el enunciado que se había presentado previamente.

En conclusión, la hipótesis de que la comprensión de la negación requiere de

doble procesamiento y efectos tardíos (750-1500 ms) parece tambalearse; primero

porque se han encontrado efectos tempranos (250-400 ms) y segundo porque los efectos

tardíos encontrados podrían deberse a la inferencia o conversión desde el modelo

negativo al modelo alternativo afirmativo, inferencia que pudiera no ser necesaria para

la comprensión de la negación. Nuestra hipótesis y la que vamos a tratar de defender en


42

la primera parte de la tesis es que el doble procesamiento depende de la información que

hay disponible, concretamente del tamaño del conjunto complementario o número de

alternativas, o incluso una tarea como la verificación podría favorecer la disponibilidad.

En líneas generales, podríamos suponer que nuestro sistema cognitivo sustituye el

modelo negativo por otro modelo alternativo afirmativo siempre que sea posible como

ocurre en aquellos casos donde hay una alternativa o contrario claro, accesible

(condición binaria). Por tanto para estos casos, es predecible que se facilite el doble

procesamiento. Sin embargo, cuando esto no es posible, el sistema cognitivo podría

mantener el modelo negativo más que sustituirlo por varios modelos alternativos

afirmativos (condición múltiple), los cuales podrían suponer una sobrecarga para la

memoria (Johnson-Laird, 2001).

3. Representación del operador negativo

Uno de los axiomas más importantes en Ciencia Cognitiva es que las personas son

capaces de representar el conocimiento que adquieren del mundo que les rodea. Una

representación, en términos de Peirce (ver Peirce 1931-1958), y probablemente la

concepción más aceptada por la mayoría de los psicólogos cognitivos, es una triada

formada por un signo, un intérprete y un objeto, es decir, para que una representación

funcione se necesita un sujeto (intérprete) que interpreta una realidad (objeto) a través

de un signo. La relación entre el objeto y el signo que lo representa puede ser a través de

un icono o un símbolo. Un icono es una representación en la que el signo mantiene las

mismas propiedades y relaciones que el objeto que representa. El ejemplo más sencillo

sería una imagen (p.e. un círculo rojo). El símbolo es una representación abstracta de


43

cualquier nombre, adjetivo o verbo, y se caracteriza por no mantener las mismas

propiedades y relaciones que el objeto que representa. Por ejemplo, el lenguaje en sí

(ver Von Eckardt, 1993 para una completa revisión del concepto).

Hay varias teorías generales que han planteado cómo podrían ser las

representaciones mentales. La teoría corpórea defiende que son icónicas, es decir, son

analógicas al objeto que representa (Barsalou, 1999; 2005; Zwaan & Radvansky, 1998).

Una propuesta completamente opuesta sería la teoría proposicional, la cual supone que

las representaciones son simbólicas, es decir, no tienen las mismas propiedades que el

objeto que representan, sino que se componen de proposiciones (Carpenter & Just,

1975; Clark & Chase, 1972). La teoría proposicional, sin embargo, no niega la

existencia de las imágenes, sino el hecho de que éstas sirvan para explicar el

funcionamiento de nuestro sistema cognitivo, es decir, de alguna manera las considera

epifenoménicas. De la misma manera, la teoría corpórea defiende que el lenguaje en sí,

o cualquier abstracción derivada de éste, no es la base del significado lingüístico.

Un modelo híbrido sería la teoría de modelos mentales. Su principal promotor,

Johnson-Laird (1983), entiende que la información puede ser representada en diferentes

formatos: el modelo mental, la proposición, y la imagen, dejando fuera las reglas

lógicas. Una imagen representa un objeto, mientras que una proposición sería la

descripción del objeto o diferentes descripciones de éste; la imagen guarda una relación

analógica con el objeto que representa mientras que este no es el caso para la

proposición; una imagen puede ser rotada y transformada haciéndola corresponder con

el objeto mientras que una proposición puede ser verdadera o falsa con respecto al

objeto. La imagen sería un tipo específico de modelo mental. Un modelo mental es una

representación icónica o analógica al objeto que representa, y según esta teoría sería el


44

modo con el cual las personas comprenden y razonan sobre el mundo mientras que las

proposiciones sólo permitirían una comprensión superficial (vocabulario y gramática).

Además, desde este enfoque se admite que los modelos mentales pueden combinarse

con representaciones simbólicas. Este sería por ejemplo el caso de la negación como

estudiaremos más adelante (para una revisión, Khemlani y cols., 2012). En resumen,

podemos considerar la teoría de modelos mentales un enfoque flexible sobre la

comprensión.

La diferencia entre la teoría de modelos mentales y la proposicional es que

mientras que la primera defiende que las personas para comprender construyen un

modelo mental, la segunda defiende que las personas representan proposiciones. Para la

teoría de modelos mentales, las proposiciones serían descripciones de los modelos

mentales. Tanto la teoría de modelos mentales como la teoría corpórea defienden la

existencia de los modelos mentales (o de situación, Zwaan & Radvansky, 1998); la

diferencia es que mientras que la teoría corpórea entiende que la comprensión se basa

exclusivamente en representaciones icónicas, la teoría de modelos mentales acepta la

existencia de otros formatos de representación, y su combinación.

Según la teoría proposicional la negación se representaría de forma lingüística y

encapsularía el argumento sobre el que se aplica. Por ejemplo, ‘El círculo no está a la

derecha del triángulo’ se representaría algo como:

No(a-la-derecha-de (círculo-triángulo)).

Según la teoría corpórea el operador negativo no puede ser representado

explícitamente, por lo que las personas construirían un modelo alternativo afirmativo,

por ejemplo, podría representar la frase anterior a través de un modelo con un círculo a

la izquierda del triángulo. La teoría de modelos mentales defiende que la negación


45

puede ser representada de forma icónica, pero esto sería una de las formas en que se

podría representar. Es decir, el individuo podría representar el círculo a la izquierda o

arriba o abajo o detrás o delante, etc., pero cada una de las representaciones no podría

captar el significado de la negación en sí, por lo que también defiende una

representación simbólica. Es decir, las personas podrían representar un modelo mental

de un círculo a la derecha de un triángulo precedido por un símbolo que representara la

negación.

¬

Durante un tiempo se consideró que los seres humanos éramos seres racionales

que procesábamos y representábamos proposiciones. Fue a partir de los años 70 cuando

los psicólogos experimentales empezaron a mostrar que la comprensión implicaba la

construcción de modelos mentales, y no solamente la formación de representaciones

proposicionales (Johnson-Laird, 1983). Los primeros indicios que hicieron cambiar de

perspectiva fueron estudios sobre memoria (Barclay, 1973; Bransford, Barclay, &

Franks, 1972; De Soto, London, & Handel, 1965). En estos estudios se presentaban

historias para recodar y encontraron que más que retener la información superficial

lingüística, se retenía información semántica profunda a través de modelos mentales, y

después describían esos modelos, a veces, con palabras diferentes a las que se habían

utilizado en las historias. Esta evidencia sugiere que las personas construyen modelos

mentales tal como la teoría de modelos mentales y la teoría corpórea defiende. La

diferencia entre ambas teorías sería que mientras que la teoría de modelos mentales

defiende otros formatos de representación, este no es el caso para la teoría corpórea.

Consecuentemente, uno de los objetivos que nos proponemos en la presente tesis es

testar ambas teorías. Este debate puede resultar novedoso ya que la mayoría de la


46

literatura sobre ambas teorías ha tendido a contrastarlas de manera casi exclusiva con la

teoría proposicional (simbólica).

4. Estudiando la negación a través de los movimientos oculares

En los estudios que presentaremos más adelante el procesamiento y la representación de

la negación es estudiado a través de medidas conductuales como los errores que se

cometen en la realización de una tarea y el tiempo que se tarda en desempeñarla. Estas

dos medidas están relacionadas con la complejidad del proceso cognitivo que se está

midiendo, tal que a mayor dificultad en el procesamiento de una tarea determinada le

suelen seguir un mayor número de errores y tiempo de respuesta más largos. Al ser

estas dos medidas ampliamente estudiadas en ciencia cognitiva (Donders, 1969), en este

apartado describiremos otra medida conductual que es menos conocida, la fijación de la

mirada al objeto de interés. Esta medida además de informar sobre la complejidad del

proceso cognitivo en general, registra información espacial y temporal del objeto que

está siendo atendiendo visualmente en cada momento y esta información está

directamente relacionada con el procesamiento cognitivo. La relevancia de la fijación de

la mirada para el estudio de la cognición fue promovida por Just y Carpenter (1976)

bajo lo que se conoce como la hipótesis fuerte de la relación ojo-mente. Según ésta,

existe una relación directa e inmediata entre fijación y procesamiento cognitivo, tal que

lo que está siendo fijado, por ejemplo una palabra, es instantáneamente procesada, y lo

es además durante tanto tiempo como dure la propia fijación. Los trabajos que aquí

presentamos comparten lo esencial de esta hipótesis, aunque somos también plenamente

conscientes de que la información que no es fijada visualmente también puede ser


47

procesada, como bien indica la amplia literatura sobre atención encubierta (por ej.,

Posner, 1980).

En general, los ojos son los órganos a través de los cuales se conoce el mundo

que nos rodea. Para llevar a cabo esta función, los ojos realizan principalmente dos tipos

de movimientos: unos, los movimientos de la fijación, se dirigen a compensar el

movimiento de la cabeza y los objetos del campo visual, con el objetivo de mantener

fija una imagen visual en la fóvea. Los otros, los movimientos sacádicos, que permiten

el barrido del campo visual y, por tanto, la captación de los objetos de interés sobre los

que la mirada queda finalmente fijada. Los movimientos sacádicos son movimientos

rápidos cuya función principal es detectar el objeto de interés y mantenerlo en la fóvea.

Una vez que el objeto es detectado, el ojo se mantiene relativamente estable para

atender y procesar dicho objeto. A este periodo estable del ojo se denomina fijación y se

relaciona con varios procesos cognitivos como la atención, el lenguaje, y la memoria

entre otros (Allopenna, Magnuson, & Tanenhaus, 1998; Altmann & Kamide, 2004;

Duñabeitia y cols., 2009; Hayhoe & Ballard, 2005; Lawrence, Myerson, & Abrams,

2004; Liversedge & Findlay, 2000; Rayner, 1978; 1998; Tanenhaus y cols., 1995).

En nuestro caso, las fijaciones de los ojos se van a medir a través de un aparato

llamado SR Research EyeLink II, que consta de un ordenador donde se presenta el

experimento, un ordenador que registra el movimiento de los ojos, y un casco que

consta de tres cámaras, una para cada ojo más otra que registra la pantalla (Figura 1).

Antes de empezar cualquier experimento hay que calibrar y validar la medida. Para ello

aparece en la pantalla nueve puntos uno detrás de otro y el participante tiene que mirar

al punto. Lo que se registra entonces es la desviación o no entre donde aparece el punto

y donde miran los ojos, su coincidencia indica que el registro es válido. Además de esta


48

medida obtenida en la calibración, la velocidad y la aceleración media es la que se tiene

en cuenta para saber lo que pasa durante el experimento. Por ejemplo, una velocidad y

una aceleración del ojo que sea superior a la calibración es considerada un movimiento

sacádico, mientras que el no registro del movimiento de los ojos se considera un

parpadeo. Cuando no es un movimiento sacádico ni un parpadeo se considera una

fijación.

Figura 1. Laboratorio de movimientos oculares

En los experimentos que se presentan más adelante utilizamos el paradigma de

‘mundo visual’ (del inglés ‘Visual World Paradigm’) para el estudio del impacto del

procesamiento de la negación sobre la exploración visual del medio. Este paradigma

consiste en la presentación oral de una palabra o enunciado mientras que los sujetos


49

están viendo en la pantalla elementos visuales que pueden estar o no relacionados con la

información presentada de forma oral (para una revisión: Huettig, Rommers, & Meyer,

2011). La suposición básica, en línea con la hipótesis ojo-mente, es que las personas

exploran la pantalla en consonancia con la información que les ha sido presentada

verbalmente, y que este proceso de relación entre interpretación y acción (fijación de la

mirada) ocurre de manera automática (Cooper, 1974; Tanenhaus y col., 1995).

El uso del paradigma de ‘mundo visual’ ha producido varios hallazgos

interesantes en relación a los mecanismos lingüísticos. Por ejemplo, Altmann y Kamide

(1999), en un estudio dirigido al análisis de los mecanismos anticipatorios del lenguaje,

mostraron que sus participantes, cuando escuchaban la frase ‘el niño se comerá un

pastel’, fijaban la mirada hacia el pastel que aparecía en una escena visual ya en el

momento de escuchar el verbo comer, antes incluso de escuchar la palabra ‘pastel’. A

nivel léxico, se ha encontrado que las fijaciones pueden dirigirse hacia objetos visuales

relacionados con las palabras oídas. Así, por ejemplo, Duñabeitia y colaboradores

(2009) encontraron que las personas miraban a una nariz cuando escuchaban la palabra

‘oler’. En relación con el objetivo de la presente tesis, estos hallazgos sugieren que este

paradigma puede ser útil en el estudio de la negación, puesto que permiten predecir que

los enunciados afirmativos y negativos quizás conducen a fijaciones sobre elementos

diferentes de una escena visual, o también a patrones de fijación distintos sobre un

mismo elemento. Por ejemplo, ante la presentación oral de la frase ‘La figura es roja’, es

de esperar que las fijaciones se dirijan hacia una figura roja, manteniéndose en ella tanto

tiempo como dure el proceso de comprensión. Mientras que para su versión negada (‘La

figura no es roja’) se puede predecir que primero miren a la figura roja y después

cambien a otros elementos o figuras de diferente color al rojo. En este sentido, uno de


50

los objetivos de la tesis es explorar si para la negación el cambio de atención, tal y como

éste es indicado por la fijación de la mirada, automática y necesariamente va desde el

elemento visual que representa el argumento u objeto negado hacia un elemento

diferente o alternativo. La importancia de profundizar en el procesamiento de la

negación estriba en su conexión con las teorías de la representación, como se ha

comentado previamente.

Antes de terminar este apartado, es necesario abordar, dada su controversia, el

tema del análisis de las fijaciones en el contexto del paradigma de ‘mundo visual’. La

mayoría de los estudios utilizan pruebas paramétricas como el análisis de varianza

(ANOVA), sin embargo, algunos autores defienden que éste no es un método adecuado

ya que los movimientos oculares, y particularmente las fijaciones, no cumplen con los

supuestos de estas pruebas estadísticas (ver: Barr, 2008; Jaeger, 2008).

Una hipótesis frecuente en psicología es aquella que utiliza una variable

independiente categórica (por ejemplo, la polaridad de un enunciado: afirmativo o

negativo) y una variable dependiente continua, tal como el tiempo de reacción o el

número de errores. Sin embargo, cuando se utiliza la técnica de movimientos oculares

estamos tratando con una variable independiente continua (el tiempo) y una variable

dependiente categórica (la región de interés sobre la que se produce la fijación). Lo que

generalmente se suele hacer para usar el análisis de varianza es ‘discretizar’ la variable

continua tiempo en intervalos y así tenemos intervalo 1, intervalo 2, etc. Esta solución

puede originar conclusiones erróneas relacionadas con efectos anticipatorios o de ratio

(ver Barr, 2008). Para evitar este problema se ha recomendado, entre otras alternativas,

el uso de modelos de regresión para analizar el cambio de la variable dependiente en

función del tiempo. Adoptando esta posible solución queda pendiente todavía el


51

problema de que la variable dependiente es categórica y como tal sigue una distribución

multinominal más que normal. Este problema es compartido por el análisis de varianza

(ANOVA), para cuyo uso es necesario que la variable dependiente cumpla unos

supuestos, que son:

1. La variable dependiente debe medirse al menos a nivel de intervalo

2. Independencia de observaciones

3. La distribución de los residuales debe ser normal

4. Homogeneidad de varianza.

Para solucionar el problema de que la variable dependiente es categórica

(formada por cada una de las regiones en la se divide el espacio de la pantalla) se utiliza

la probabilidad de que el sujeto mire a dicha región. Pero utilizar la probabilidad plantea

otro problema ya que los valores que puede tomar están limitados, entre 0 y 1, y por

tanto el error de la varianza es proporcional a la media. En cambio, el ANOVA supone

que el rango de valores de la variable dependiente es ilimitado y que los errores se

distribuyen de forma normal e independiente de la media. Para solucionar este nuevo

problema se transforma las proporciones en odds y se obtiene su logaritmo (y=ln(p/1-p),

donde ln es el logaritmo neperiano, p es la proporción de fijaciones hacia el objeto de

interés e y es el valor obtenido de la transformación de p, Jaeger, 2008).

Llegados a este punto, seguimos teniendo otro problema ya que las

observaciones son dependientes. Es decir, la probabilidad de que se mire a la posición

de interés es dependiente de que no se mire al resto de posiciones, y todas ellas suman

1. Para solucionar este problema, los modelos de efectos mixtos (o multiniveles) son

adecuados ya que modelan la no dependencia. Por tanto, Barr (2008) propone que el

mejor modelo para analizar los movimientos oculares es el modelo de regresión


52

logística de efectos mixtos (o multinivel), ya que los modelos de regresión son

adecuados para acomodar la variable continua del tiempo, los modelos logísticos son

necesarios para acomodar una variable dependiente categórica, y los modelos de efectos

mixtos atienden a la no dependencia de observaciones.

Otros análisis también han sido propuestos. Por ejemplo, Scheepers (2003)

utilizó modelos lineales logísticos para analizar los movimientos oculares. Estos

modelos son óptimos para el análisis de variables categóricas puesto que no asumen

normalidad u homogeneidad de varianza. Scheepers, Keller y Lapata (2008) utilizaron

el modelo logístico ‘logistic power peak’ (LPP) en otro estudio. Heller, Grodner, y

Tanenhaus (2008) calcularon la proporción de fijaciones en el target con respecto a la

suma de la proporción de fijaciones en el target y los distractores. Para evitar problemas

relacionados con la proporción de los datos, las medias de los participantes y los ítems

fueron transformadas utilizando modelos quasi-logit antes del análisis de varianza

(ANOVA). Ferguson, Scheepers, y Sanford (2010) obtuvieron la probabilidad de

fijación en el target usando su logaritmo y luego analizaron los datos utilizando análisis

de clúster y finalmente ANOVA. Mirman, Dixon, y Magnuson (2008) también

propusieron utilizar un análisis de curvas de crecimientos para no sólo analizar el

tiempo correctamente sino también tener en cuenta las diferencias individuales de los

sujetos.

Esta diversidad de modelos estadísticos utilizados para el análisis de los

movimientos oculares podría originar la imposibilidad de comparar unos estudios con

otros, por lo que es necesario que los investigadores se pongan de acuerdo sobre cuál es

el mejor modelo para analizar el curso temporal de las fijaciones. Aunque, también es

cierto que el uso de un modelo u otro debe depender de la hipótesis del investigador y


53

los datos. Por ejemplo, uno de los objetivos de la tesis es explorar si la conversión de un

modelo negativo a su alternativo afirmativo es necesaria, es decir, tenemos dos objetos

de interés: el que corresponde al modelo negativo y a su alternativo afirmativo, en

algunos casos incluso todos los elementos son de interés porque había varios

alternativos posibles. Este tipo de exploración no puede hacerse con el mejor estadístico

para el análisis de los movimientos oculares propuesto, el modelo de regresión logístico

de efectos mixtos, porque éste no explora el momento en el que cambia una distribución

de un objeto a otro, más bien indica el incremento o disminución de un objeto de interés

o las diferencias de ese objeto entre las condiciones. Por otro lado, el análisis de

funciones no lineales tampoco se puede utilizar para explorar nuestra hipótesis porque,

como veremos, algunas de las manipulaciones que hemos introducido conducen a

distribuciones de fijaciones diferentes para las condiciones que se pretenden comparar,

y por tanto requeriría el uso de funciones diferentes para cada una de ellas. Además

estos análisis indican si hay diferencias en la proporción de fijaciones, pero no indican

el momento temporal, y nosotros estamos muy interesados en el curso temporal de la

negación. Por tanto, aunque parece que hay un modelo estadístico adecuado para

analizar los movimientos oculares, es importante tener en cuenta que los datos y la

hipótesis son los que realmente deben determinar qué método estadístico es el adecuado

y eso hemos tratado de hacer en los trabajos con movimientos oculares que

presentaremos a continuación.


54

5. Objetivos

El principal objetivo de la presente tesis se dirige a deshojar una de las palabras

esenciales del lenguaje, la negación, para estudiar su complejidad en la comprensión.

Son muchos los estudios que han analizado diferentes factores para dar respuesta a esta

cuestión, sin embargo, al día de hoy sigue siendo una cuestión irresoluble. Para avanzar

es su conocimiento, nosotros vamos a atender al concepto propio de la negación para

inferir las primeras conclusiones que se derivan de él y que son las que vamos a testar

en la presente tesis.

Desde Aristóteles, como hemos dicho previamente, la negación se define como

un elemento sintáctico que coge un argumento (por ej., rojo) y revierte su valor de

verdad (por ej., no rojo) de falso a verdadero, o viceversa.

Este concepto, revertir el valor de verdad, es simbólico. Es decir, no hay nada en

el mundo real (externo) que corresponda con dicha función. El primer objetivo que nos

planteamos entonces es demostrar que las personas pueden comprender la negación (por

ej., La figura no es roja) de forma simbólica, es decir, representando exclusivamente el

modelo negado (por ej., no figura roja). Ahora bien, cuando la alternativa sea accesible,

los individuos tenderán a convertir la negación en su alternativa afirmativa (por ej., una

figura verde) puesto que como hemos comentado previamente, es más fácil recordar

información en afirmativo que negativo. Estas dos formas de comprender la negación

estarían relacionadas con la representación de la negación, en el primer caso, la

representación sería simbólica ya que la negación está representada explícitamente y la

única forma de representarla es simbólica; y en el segundo, icónica, puesto que la

negación no se representaría explícitamente. Como consecuencia este objetivo nos


55

permitiría discriminar entre teorías representacionales: la teoría de los modelos mentales

y la teoría corpórea.

De la definición de negación también se desprende que la negación coge un

argumento verdadero o falso y lo convierte en falso o verdadero. Esto significa que la

negación se aplica a una proposición, la cual puede ser verdadera o falsa, sin embargo

este no es el caso de la imagen. Tal y como hemos indicado previamente, una imagen

puede ser rotada y transformada haciéndola corresponder con el objeto mientras que

solo una proposición puede ser verdadera o falsa con respecto al objeto. Con lo cual, la

propia definición de la negación nos lleva a pensar que la negación no se aplica

directamente sobre una imagen (o representación visual), principal ventaja de las

palabras concretas frente a las abstractas, y esto nos lleva a hipotetizar que argumentos

simbólicos (o no visuales) pudieran facilitar la comprensión de la negación frente a

argumentos icónicos (o visuales). De corroborar esta hipótesis, la idea de que la

negación sea simbólica se vería fortalecía.

Con estos dos trabajos habríamos descartado que la dificultad de la negación se

deba a su doble procesamiento o su representación simbólica como algunos estudios

han propuesto ya que habríamos encontrado que la negación se puede comprender en un

solo paso representando la situación negada y además habríamos probado que la

representación simbólica aunque suele ser más difícil que la icónica, no sería el caso

para la negación, que podría incluso facilitarla. El tercer y último objetivo de la tesis es

demostrar que la dificultad de la negación con respecto a la afirmación es semántica

(Miller, 1962), es decir, la negación añade información semántica con respecto a su

correspondiente afirmativa. La negación coge un argumento afirmativo y revierte su

valor de verdad de falso a verdadero o viceversa. Para demostrar esta hipótesis


56

utilizaremos la pragmática presentando ambos tipos de enunciados en varios contextos.

Si nuestra hipótesis es cierta, cuando la afirmación se presente en un contexto para

falsar la información previa, principal uso de la negación, entonces ambos tipos de

enunciados serán procesados en el mismo momento temporal y resultarán iguales de

fáciles o difíciles. Fuera de este contexto, la negación se mostrará más difícil que la

afirmación porque su principal uso es falsar o contradecir la información previa, y ésta

función es más compleja que la afirmación, que generalmente presenta información

consistente con la previa conversación.

How negation is understood

57

6. How negation is understood: Evidence from the visual world paradigm

6.1. Abstract

This chapter explores for the first time how negation is understood using the visual

world paradigm. Two-step theory assumes that the comprehension of negative

sentences, such as the figure was not red, necessarily involves the simulation of the

actual situation (e.g., a green figure), while mental model theory claims that individuals

might retain a symbolic representation of the negated situation (e.g., a non-red figure)

when an analogical representation is awkward or unfeasible. Our hypothesis is that

people will switch to the actual situation whenever possible, but will be able to maintain

a symbolic representation of the negated situation when needed. To test this, we studied

the role of context and task in the availability of the actual situation in three visual

world paradigm experiments. Experiment 1 presented either a specific context (binary:

the figure could be red or green) or an unspecified context (multary: the figure could be

red or green or yellow or blue). Then, affirmative and negative sentences (e.g., the

figure is (not) red) were heard while four figures were shown on the screen and eye

movements were monitored. We found that people shifted their visual attention toward

the actual situation in the binary context, but focused on the negated situation in the

multary context. This latter result is corroborated in Experiments 2 and 3, in which

negative sentences were presented without any context using two different tasks:

recognition and verification. Our findings suggest that individuals are able to represent

negation symbolically, but readily switch to the actual situation when the context

permits.


58

6.2. Introduction

There is growing evidence in the literature that language comprehension makes use of

analogical representations in the form of models (Barsalou, 2005; Glenberg, Meyer, &

Lindem, 1987; Johnson-Laird, 1983; Zwaan & Radvansky, 1998). However, there are at

least two different views on how these representations are used. On the one hand,

embodiment theory holds that all representations, including those relating to abstract

concepts, must be iconic to the world (Barsalou, 1999; 2005; 2012; Glenberg et al.,

1987; Lakoff & Johnson, 1980; Zwaan & Radvansky, 1998). According to this theory,

symbolic representations are foreign to the human mind. On the other hand, mental

model theory, while holding that most representations are iconic, also allows for the use

of combinations with symbolic representations (Johnson-Laird, 1983; 2006). An

example of this combination can be seen in the processing of negation (Khemlani,

Orenes, & Johnson-Laird, 2012). Both views posit the existence of iconic situation

models, but differ in that the mental model theory also claims that symbolic

representations exist, while the embodiment theory holds that representations are

exclusively iconic. In the present study, we will contrast these two views in three

experiments using negation. Our main hypothesis is that people will switch to the actual

situation whenever possible, but will be able to maintain a symbolic representation of

the negated situation when needed. This represents a new approach to the question: in

the past, the two theories in question have been compared with propositional theories

using exclusively symbolic representation systems (Clark & Chase, 1972; MacDonald

& Just, 1989), but this is the first time they will be compared with each other.


59

Negation is an operator that takes a single argument and reverses its truth value.

In other words, if A is an argument that is false (e.g., Jefferson was the president of the

United States), then Not-A is necessarily true (e.g., Jefferson was not the president of

the United States), an analysis that goes back to Aristotle (1984). As the meaning of

negation has no direct equivalence in experience, it represents a challenge for

embodiment theory. Nevertheless, a theory of negation has recently been proposed (the

two-step simulation theory or two-step theory, for short) that, in the spirit of the

embodiment view, excludes symbolic and linguistic-like representations of any kind

(Kaup, Lüdtke, & Zwaan, 2006). According to the two-step theory, negation cannot be

represented explicitly, and so the comprehension of a sentence such as the door is not

open must be accomplished through two representational steps (Kaup et al., 2006). The

first step is represented via a perceptual simulation of the negated situation that

corresponds to the affirmative equivalent (e.g., an open door); in a second step

occurring 750-1500 ms later, this perceptual simulation is changed to the actual

situation implied by the negative (e.g., a closed door). This theory also holds that these

two steps are mandatory for comprehension.

This requirement that there must be a shift from one simulation to the other

would appear to be justified for sentences such as the one used in the above example

(the door is not open). For this sentence, a simulation of the actual situation (a closed

door) is readily inferred from its binary (or complementary) predicate: in the case of

‘not open’, there are only one alternative, ‘closed’. Negative sentences are not always

this informative about the actual situation, however. For instance, the multary (or

contrastive) predicate in a sentence such as the door is not blue has many alternatives

(‘red’, ‘green’, ‘yellow’, etc.), and so there is no clear actual situation that can be


60

simulated. In fact, it seems impossible to know what the door actually looks like, unless

additional information is provided. The two-step theory holds, however, that even in

cases of uncertainty such as the one given above, a simulation of the actual situation

might take place, although this simulation could be empty (see Barsalou, 1999). For

example, the door is not blue could well be simulated by representing a door of an

unspecified color (Kaup, Zwaan, & Lüdtke, 2007). However, this case has not yet been

shown to occur.

Mental model theory agrees with the possibility that people might simulate the

actual situation for multary predicates, but holds that they are able to retain the negated

situation while applying a symbol that represents negation (Khemlani et al., 2012).

Consider the following assertion: the circle is not to the right of the triangle. Mental

model theory argues that individuals, in order to understand this situation, will construct

an iconic mental model of the corresponding affirmative assertion and then apply the

negation symbol. The resulting model might look like this:

¬

In this sense, Giora and colleagues have also proposed the suppression/retention

hypothesis, which argues that suppression following negation (i.e. the change toward

the actual situation) is not mandatory, but sensitive to discourse goals and requirements

(Giora, 2006; Giora et al., 2007; Giora et al., 2009; see also for a similar idea Schul,

2011). Wason (1961) was the first psychologist to discover that individuals replace the

negated situation with the actual situation when it is available, such as in the case of

binary predicates. Watson (1979) also observed that children did the same for multary

predicates, although they retained the negated situation in the case of adjectives that


61

express loss or absence, such as the horse has no tail. Beltrán, Orenes and Santamaría

(2008) corroborated those results in adults, and also found that individuals produced

more negations for multary predicates than for binary predicates. These studies support

the idea that people are able to represent negation through either its actual situation or

its negated situation, as mental model theory claims. What they represent in each case

will depend on the availability of the actual situation. In the case of binary predicates

(e.g., open-closed), the actual situation is readily available, whereas in the case of

multary predicates (e.g., blue-red-green-yellow), the correspondence with the actual

situation, unless it is obvious from the context, is not straightforward. As those studies

used a production task, it is necessary to test whether those results are similar for

comprehension. Kaup and collaborators (2006) showed that people changed to the

actual situation when people understand negation using binary predicates, the main goal

of this study then is to know whether people maintain the negated situation when they

understand negation using multary predicates.

To test this, we studied the role of context and task in the availability of the

actual situation in three visual world paradigm experiments. In a typical visual world

task, verbal and visual inputs are presented simultaneously while eye movements are

recorded. Experiments have shown that when linguistic input matches visual input, the

eyes will begin to move automatically towards the corresponding visual input (Cooper,

1974; Tanenhaus et al., 1995). These results suggest that it is the conceptual overlap

between the word and the object that mediates between language and eye movements.

These data on semantic relatedness rule out an account based solely on phonological

overlap between the unfolding word and the names associated with the objects in the

scene (Altmann, 2011). Eye movements are thus presumed to reflect interactions


62

between linguistic and visual representations that occur at the level of conceptual

representation (Salverda, Brown, & Tanenhaus, 2011).

In keeping with the above assumptions, it follows that when people are exposed

to negative assertions in a visual world paradigm, they will look more frequently at

what they are using to process and represent the assertion. The advantage of the visual

world paradigm for studying negation is that all the objects (whether or not they are

related to the comprehension of the sentence) are displayed on the screen, and so people

are free to turn their attention to whatever object is required for processing and

representation. With respect to the timing of the display of the input, most of the

paradigms applied thus far in research on negation have opted for using a discrete delay

between the sentences and the pictures. For example, Lüdtke and collaborators (2008)

employed a sentence-picture verification paradigm using event-related potentials (ERP)

in which participants were presented with affirmative or negative sentences (e.g., in

front of the house there was a/no cat) followed by a matching or mismatching picture

250 or 1500ms later. The results showed that when the delay in the picture presentation

was short (250 ms), verification latencies as well as the ERPs evoked by the picture

showed an interaction between negation and truth value. In contrast, when the delay was

long (1500 ms), main effects of truth value and negation were observed, in addition to

the interaction effect in the N400 time window. These results suggest that negation is

fully integrated into sentence meaning only at a later stage of the comprehension

process. As we have seen, the authors interpreted this to mean that the comprehension

of negated sentences happens around 1500 ms. However, sentence comprehension

should not take that long, and so it might be worthwhile to use another methodology to

record what is happening in that lengthy period of time.


63

Using the visual world paradigm, we presented affirmative and negative

sentences (e.g., the figure was (not) red) via a loudspeaker while four colored figures

(e.g., yellow, blue, green, and red) were shown on the screen. One of the colors

represented the negated situation (e.g., the red figure) while the others stood for the

actual situation (e.g., the yellow, blue, and green figures). With this design, the

participants (and not the researchers) were able to manage the pace of their

comprehension, thus allowing us to determine the temporal course of negation. Also,

our use of the visual world paradigm allowed us to determine what people were looking

at when comprehending negative sentences: did they focus on the negated situation or

the actual situation? This approach has clear implications for helping to discriminate

between the two theories under comparison.

We carried out three experiments in all. The goal of Experiment 1 was to

determine how people process negative sentences (e.g., the figure was not red) in binary

(e.g., the figure could be red or green) and multary contexts (e.g., the figure could be

red, or green, or blue, or yellow). According to mental model theory, the predicted

outcome would be that the participants would shift their visual attention from the

negated situation (e.g., a red figure) toward the actual situation (e.g., a green figure) in

binary contexts (as Kaup et al. (2006) found), while they would keep their visual

attention on the negated situation in multary contexts. In Experiment 2, we presented

affirmative and negative sentences without any verbal context. This condition

corresponds with the multary context in Experiment 1, and so we expected that the

findings would be the same. The purpose of this second experiment was to control for

any possible influences of context. Many studies have shown that the processing of

negation is facilitated when assertions are presented in a suitable context (Dale &


64

Duran, 2011; Givon, 1978; Glenberg et al., 1999; Johnson-Laird & Tridgell, 1972;

Nieuwland & Kuperberg, 2008; Strawson, 1952; Tian, Breheny, & Ferguson, 2010;

Wason, 1965). Also, Salverda and Altmann (2011; Soto & Humphreys, 2007) showed

that context activates the concepts that guide processing; it is therefore appropriate to

test the role of context in the processing of negation.

Experiments 1 and 2 employed a recognition task (e.g., were the figures

circles?) which was the same as the one used by Kaup et al. (2006). In both studies,

participants were asked about the identity of the picture that was presented on the

screen; the question was not related to the meaning of the sentences themselves (see

also Zwaan, Stanfield, & Yaxley, 2002). This task should be considered more

ecological than a task requiring comprehension (such as a verification task), which

could modulate the processing of negation; it is well known that such tasks affect

processing (Clark & Chase, 1972; Jones, 1966; 1968), and moreover, language

comprehension does not usually require any specific task to be carried out. Some may

question our decision to use a recognition task, arguing that this type of task does not

imply full comprehension of the sentence’s meaning, with the resulting danger that

participants might not necessarily be interpreting the affirmative and negative

assertions, but merely making an associative response to them. In support of this

argument, it should be pointed out that Evans (1972) found that individuals showed a

tendency to pay attention only to the arguments that have been presented in the

premises, regardless of whether they are affirmative or negative (this effect was called

the ‘matching bias’). To control for this unlikely effect, we decided to replicate

Experiment 2, but with a verification task, in which people needed to understand the

sentences in order to give the right response. This is what we did in Experiment 3. We


65

predicted that the type of task would not influence the results and that the findings for

Experiments 2 and 3 would be the same.

6.3. Experiment 1

The goal of Experiment 1 was to test whether, on hearing negative sentences in the

binary (e.g., the figure could be red or green) and multary (e.g., the figure could be red,

or green, or blue, or yellow) contexts, participants would shift their visual attention

from figures representing the negated (mentioned) situation towards figures

representing the actual (alternative) situation. To that end, we designed a visual world

experiment in which participants heard affirmative and negative sentences while

exploring a display with four colored figures, and examined the patterns of participants’

fixations on the figures when these sentences were preceded by one of two different

spoken contexts: 1) a binary context that mentioned two of the four figures in the

display, and 2) a multary context that mentioned all the figures in the display.

The predictions supported by current theories differ for binary and multary

contexts. Mental model theory makes the following predictions about performance in

the task: if an affirmative assertion, such as the figure is red, occurs in either context,

there should be an increase in fixations on the red figure referred to in the assertion. If a

negative assertion, such as the figure is not red, occurs in a binary context (e.g., the

figure could be red or green), there should be an increase in fixations on the actual

(alternative) figure, i.e. the green one. This result would support the idea that people

switch to the (analogical) representation of the actual situation whenever possible.

However, if the negative assertion occurs in the multary context (e.g., the figure could


66

be red, or green, or blue, or yellow), there should be an increase in fixations on the red

figure referred to in the assertion. This latter prediction is crucial. Its corroboration

supports the possibility of a symbolic interpretation of negation as posited by mental

model theory, rather than the hypothesis that negation always calls for the simulation of

the actual situation, as held by the two-step theory. Indeed, two-step theory would

predict the same results as mental model theory as explained above, except in the

multary context, where it predicts that the results will be similar to the binary context

for negative sentences, i.e. that there will be an increase in fixations on the alternatives.

Kaup et al. (2007) also claimed that it would be possible for the actual situation to

remain empty or unspecified (Barsalou, 1999). In that case, the theory predicts that the

proportion of fixations on the mentioned color (e.g., the red figure) and the alternatives

would be similar, because none of the figures is being processed.

6.3.1. Method

Participants. Thirty-one native Spanish speakers from the University of La Laguna,

Tenerife (Spain), participated in the experiment in exchange for course credits. All of

them had uncorrected vision or wore soft contact lenses or glasses.

Materials. Sixty-four experimental trials were presented to participants distributed in

four conditions. For each trial, a different display with four colored figures was shown

on the screen (see Figure 1). These figures occupied distinct quadrants of the display

and were always of different colors (yellow, blue, green and red). The same colors were

used in all the experimental displays, but with the quadrant position counterbalanced. In


67

contrast, the figures’ shape (diamonds, triangles, circles, or squares) varied across

displays, but were always the same for the four figures in each display. In other words,

all figures were of different colors but an identical shape within trials, and of the same

color but different shapes across trials.

The experimental conditions were generated from the combination of two

spoken sentences, both presented via loudspeakers. In each trial, the first sentence

established the context, which was either binary (e.g., the figure could be red or green)

or multary (e.g., the figure could be red, or green, or blue, or yellow), and the second

sentence was the target, which was referred to in either an affirmative (e.g., the figure is

red) or negative polarity form (e.g., the figure is not red). The resulting conditions were

hence: binary affirmative, binary negative, multary affirmative and multary negative. In

total, there were 16 experimental trials per condition. For all trials, the target word was

the color word mentioned in the second sentence. This target word established the onset

from which the fixation time-course was analyzed.

In addition to the figure display, a written question was also shown on the screen

at the end of each trial. This question involved the detection of the shape of the figures

in the display (e.g., were the figures circles?) and was unrelated to the spoken

sentences, which always referred to the color. In this way, the impact of speech

comprehension on fixations could be detached from the impact of the task goal.

Apparatus and Procedure. Participants’ eye movements were recorded at a rate of 500

Hz using an SR Research EyeLink II head-mounted eye-tracker connected to a 21-inch

color CRT for visual stimulus presentation. Procedures were implemented in the SR

Research Experiment Builder. Calibration and validation processes were carried out at


68

the beginning of the experiment and repeated several times per session. Trials started

with the display of a central fixation dot for drift correction (see Figure 1) while

participants listened to the context sentence that took 3500 ms. After that, a display with

the four colored figures appeared for 5500 milliseconds. The target sentence was

delivered after one second of display preview, with the target word starting 1500 ms

later for affirmatives, and 1600 ms later for negatives. The trial concluded with the

appearance of the written question (e.g., were the figures circles?), to which participants

had to answer either ‘yes’ or ‘no’, with each response being correct for half of the trials.

There was a practice block before the experimental block. The trials of this block (eight

in total) followed the same structure but used a different set of colors (gray, violet,

brown and orange). The entire experiment lasted approximately 30 minutes.

Figure 1. Procedure of Experiments 1: Recognition task (the sentences have been

translating from the Spanish).


69

6.3.2. Results

Behavioral data. Response accuracy and latency were both analyzed separately using

two-way ANOVAs with context and polarity as factors. The aim of these analyses was

to test whether there was any influence of the spoken sentences on the recognition task.

Accuracy analysis failed to show any significant sign of interference. In contrast,

latency analysis did reveal that the response times were modulated by the spoken

materials. Specifically, it showed that response latencies were slower after negative

sentences (1288 ms; sd=41) than after affirmatives (1242 ms; sd=38; F(1,30)=6.987,

p=.013, η2=.189), and were also slower after binary contexts (1282 ms; sd=41) than

after multary contexts (1248 ms; sd=38; F(1,30)=6.425, p=.017, η2=.173). These main

effects of polarity and context provide evidence of participant involvement in the

comprehension of the spoken materials.

Eye movement data. First, we will describe the procedure for analyzing the eye-

movement data generated by the EyeLink system. Bitmap templates were created for

identifying each of the regions of interest (color circles) in each display. The output of

the eye-tracker included the x and y-coordinates of participant fixations, which were

converted into region codes using templates. The time period analyzed was from 500

ms before the onset of the critical word (the color word mentioned in the affirmative or

negative assertion) to 1500 ms after the word. This time window was chosen to

guarantee that there would be enough time for participants to comprehend negations

(e.g., Kaup et al., 2006; Lüdtke et al., 2008). This period was divided into 20-ms time

slots. For each time slot, the number of fixations on each color was counted and


70

converted into fixation probabilities obtained from the four figures and the background

(Figure 2).

Fixation probabilities were obtained for display quadrants containing either 1) a

figure of the color that was mentioned in the target sentences (‘Mentioned color’; e.g., a

red figure for sentences like the figure was (not) red), 2) a figure of one of the colors

mentioned in the context sentence but not in the target sentence (‘Alternative color’; e.g.

a green figure for a context sentence like the figure could be red or green or the figure

could be red, or green, or blue, or yellow, followed by target sentences like the figure

was (not) red), or 3) a figure of a color different from any of those mentioned in the

context and target sentences (‘Other colors’; e.g., a blue figure for context sentences like

the figure could be either red or green followed by a target sentence like the figure is

(not) red).

Figure 2 shows the impact of the spoken sentences on the time course of fixation

probabilities for the Mentioned, Alternative and Other color figures. In this figure, the

graphs for affirmatives (2.a and 2.b) show that there was an increase in fixation

probabilities on the Mentioned color accompanied by a decrease in fixation probabilities

on the Alternative color in both binary and multary contexts. In contrast, the graphs for

negatives (2.c and 2.d) illustrate patterns of fixation that differ as a function of context.

Specifically, these graphs describe a time course for negative sentences in the multary

context that is similar to that of affirmatives, with an increase in fixation probabilities

on the Mentioned color and a decrease in fixations on the Alternative color. At the same

time, they reveal a reversed time course for negatives heard in the binary context, with a

decrease in fixations on the Mentioned color and an increase in fixations on the

Alternative color. This latter pattern is preceded by a short period of increased fixations


71

on Mentioned color figures, which quickly fades into the stabilization of both the

increase in fixations on the Alternative color figures and the decrease in fixations on the

Mentioned color figures. Thus, a visual inspection of the time course of fixations

suggests that contextual information only affected the fixation pattern elicited by

negative sentences.

To explore the statistical significance of the observed pattern, first we calculated

the mean fixation probabilities for 100-ms time regions from 100 to 1500 ms after

critical word onset. Given that 180-200 ms are needed to account for an eye

programming latency (Martin, Shao, & Boff, 1993), the mean of the first time region

(100-200 ms) was considered to be the baseline and was used to conduct statistical

comparisons against the means of all other 100-ms time regions (for a similar method,

see Huettig & Altmann, 2010). This correction to baseline allowed us to control for any

bias in the pattern of fixations on figures caused by the context.

Tables 1 and 2 detail mean fixation probabilities of each time region with respect

to the chosen baseline for both Mentioned and Alternative color figures and also the

significances of the corresponding t-tests against the baseline. The statistical

comparisons gave results that corresponded nicely with the visual pattern described

above.


72

Figure 2. Temporal course of affirmative (top) and negative sentences (bottom) for

Binary context (left) and Multary context (right). The onset of the critical word (the

color word mentioned in the affirmative and negative sentence) is represented by 0 on

the horizontal axis. Error bars represent 95% confidence intervals by subject, such that

no overlap between conditions indicates a significant difference. A pre-inspection of

fixation probabilities on the Other colors for binary and Alternative color for multary

context indicated no differences over time (ps>.2), so the average of these is shown as a

single line.


73

Table 1. Summary of the difference of probabilities of fixation between each region and

the baseline for the Mentioned color (MC) and Alternative (A) for affirmative and

negative sentences for the binary context. Asterisks indicate significant differences

(p<.05) with respect to the baseline and the minus sign ‘-‘ indicates a decrease of the

proportion of fixation with respect to the baseline.

Affirmative_MC Negative_MC Affirmative_A Negative_A

200-300 .0010 -.0026 .0006 -.0032

300-400 .0490* .0145 -.0261 -.0232

400-500 .1594* .0416 -.1235* -.0494*

500-600 .2742* .0758* -.2126* -.0555

600-700 .3410* .0777* -.2571* -.0258

700-800 .3671* .0506 -.2655* .0223

800-900 .3839* .0155 -.2723* .0742

900-1000 .3940* -.0129 -.2736* .1068*

1000-1100 .3814* -.0302 -.2646* .1255*

1100-1200 .3782* -.0398 -.2701* .1293*

1200-1300 .3601* -.0613 -.2638* .1416*

1300-1400 .3498* -.0875 -.2707* .1603*

1400-1500 .3394* -.1070* -.2762* .1546*

Paired t-tests showed that negative sentences in the binary context generated an

initial increment of fixation probabilities on the Mentioned color figure (first significant

value at 500-600 ms time period, t(30)=2.481, p=.019). Yet, from 900 ms onward, this

tendency changed and fixation probabilities started to increase for the Alternative color

figure (t(30)=2.512, p=.018) and decrease for the Mentioned color figure, with this

change being significant starting at 1400 ms (t(30)=-2.101, p=.044). Thus, on hearing

negative sentences in the binary context, participants shifted their visual attention from

the Mentioned color figure toward the Alternative color figure.


74


the baseline for the Mentioned color (MC) and Alternative (A) for affirmative and

negative sentences for the multary context. Asterisks indicate significant differences

(p<.05) with respect to the baseline and the minus sign ‘-‘ indicates a decrease of the

proportion of fixation with respect to the baseline.

Affirmative_MC Negative_MC Affirmative_A Negative_A

200-300 .0065 .0156 -.0018 -.0049

300-400 .0292 .0122 -.0044 -.0073

400-500 .1106* .0497* -.0252* -.0049*

500-600 .2287* .1141* -.0547* -.0343*

600-700 .3487* .1676* -.0853* -.0553*

700-800 .4184* .2277* -.1030* -.0647*

800-900 .4767* .2267* -.1152* -.0592*

900-1000 .5088* .2208* -.1224* -.0535*

1000-1100 .5245* .2071* -.1279* -.0521*

1100-1200 .5296* .1861* -.1313* -.0484*

1200-1300 .5240* .1531* -.1339* -.0423*

1300-1400 .5193* .1430* -.1323* -.0407*

1400-1500 .5067* .1371* -.1279* -.0402*

In contrast, statistical comparisons revealed that there was no shift of attention

from the Mentioned to the Alternative color figures in the case of negative sentences

heard in the multary context. For these sentences, fixation probabilities revealed instead

a prolonged increase in visual attention on the Mentioned color figure (t(30)=2.480,

p=.019), which was accompanied throughout by a decrease in fixations on the

Alternative color figures (t(30)=-2.554, p=.016) starting at 400 ms. Thus, on hearing a

negative sentence in a multary context, participants looked at the figure corresponding

to the Mentioned color, at the expense of a reduction of attention toward the figures of

an Alternative color.

Finally, an identical pattern of fixations was obtained for affirmatives in both

binary and multary contexts (see Tables 1 and 2). Just as for negatives in the multary

context, affirmative sentences induced a lengthy increase in fixation probabilities on the


75

Mentioned color as well as a decrease in the fixations toward the Alternative color

figures. Thus, on hearing an affirmative assertion, participants’ visual attention shifted

toward the figure of the Mentioned color, irrespective of whether a binary or multary

context had been provided.

6.3.3. Discussion

Experiment 1 showed that hearing negatives in a binary context causes participants’

visual attention to shift from a figure of the negated (mentioned) color towards a figure

of the actual (alternative) color. This finding confirms the two stages predicted by the

two-step theory, and suggests that during the processing of a negative assertion, there

must be a shift in the respective saliency of the negated and the actual situations.

Moreover, the specific time courses of fixations indicate that the shift was completed

around 900 ms after critical color word onset, which is in agreement with some previous

reports that the instantiation of the actual situation takes around 1 second (e.g., Kaup et

al., 2006).

Importantly, Experiment 1 also revealed that hearing negatives in a multary

context induces participants’ visual attention to remain trained on the figure of the

negated (mentioned) color throughout the period examined. This finding, unlike the

previous one, is indeed at odds with a mandatory two-step process and confirms, in

opposition to this view, that the shift from the negated to the actual situation is not a

mandatory dynamic for negation processing. As predicted by mental model theory,

when the actual situation is underspecified or indeterminate, it is the negated situation

that remains as the salient content in the course of processing.


76

Supporting this conclusion are the qualitatively similar patterns of fixation

exhibited by negatives and affirmatives in multary contexts. Irrespective of context,

affirmative sentences generated a deployment of visual attention characterized by a

progressive increase in attention to the figure of the Mentioned color accompanied by a

parallel decrease in attention to figures of the Alternative colors. This suggests that, as

in the case of negatives in multary contexts, hearing an affirmative assertion leads to the

progressive instantiation in the mind of the content that has been mentioned explicitly in

the sentence.

6.4. Experiment 2

Experiment 1 yielded evidence against a mandatory two-step dynamic for the

processing of negatives. There, we gave participants an initial verbal context that varied

in terms of the availability of the actual situation to which the subsequent affirmative or

negative sentence could be referring (binary and multary context). The goal of

Experiment 2 was to test whether the deployment of visual attention for isolated

negative sentences (without contextual constraints) would reproduce the pattern

observed for negatives in the multary context of the previous experiment. To that end,

we presented affirmative (e.g., the figure is red) and negative sentences (e.g., the figure

is not red) without any previous verbal context while a picture with four colored figures

(e.g., red, blue, green, and yellow) was shown on the screen. The predicted outcome

was that there would be an increase in the proportion of fixations on figures of the

Mentioned color in both affirmative and negative sentences, accompanied in both cases

by a decrease in fixations on the Alternative colors.


77

6.4.1. Method




Materials and Procedure. The instructions and procedure were the same as in

Experiment 1. The only difference here was that we presented affirmative and negative

sentences (16 trials of each) that were not preceded by any verbal context. Hence, the

time given to explore the display before hearing the sentences was not conditioned by

any previous verbal information.

6.4.2. Results and Discussion

Behavioral data. One participant was eliminated from the analysis because she did not

answer any questions. We only found significant differences for reaction times

(F(1,29)=5.483, p =.026, η2=.159). Participants were slower to respond to the task

questions after negative sentences (95%; 1345 ms; sd=50) than after affirmatives (93%;

1292 ms; sd=48). Again, this result can be taken as indicative of participants’

involvement in the comprehension of the verbal material, even though this was not

required by the task.


78

Eye movement data. The procedure for analyzing the eye movement data was similar to

that used in Experiment 1. We eliminated one additional subject due to problems in the

recording of her eye movements.

Figure 3. Temporal course of the Mentioned color and Other colors for affirmative

(left) and negative sentences (right) without verbal context (recognition task). The onset

of the critical word (the color word mentioned in the affirmative and negative sentence)

is represented by 0 on the horizontal axis. Error bars represent 95% confidence intervals

by subjects such that no overlap between conditions indicates a significant difference. A

pre-inspection of fixation probabilities on the Other colors indicated no differences over

time (ps>.2), so the average of these is shown as a single line.

Figure 3 shows the effect of the spoken sentences on the time course of eye

fixations on Mentioned color and Other color figures. The graph for affirmatives (Fig 3,

left) shows that there was an increase in fixations on the Mentioned color figure and a

decrease in fixations on the Other colors. We observed the same pattern for negative

sentences (Fig 3, right), with an increase in fixation on the Mentioned color and a

decrease in fixation on the Other colors.

Table 3 shows mean fixation probabilities of each time region with respect to the

baseline for both Mentioned color and Other color figures. For negative sentences, it is

observed that participants increased fixations on the Mentioned color (t(28)=3,068,


79

p=,0059) and decreased fixations on the Other colors (t(28)= 3,649, p=,001) starting at

400 ms. The same pattern was observed for affirmatives, but the increase with respect to

the baseline for the Mentioned color (t(28)= -2,266, p=.031) and the decrease for the

Other colors (t(28)= 2,863, p=,008) started at 300 ms.


the baseline for the Mentioned color (MC) and Others (O) for affirmative and negative

sentences without verbal context. Asterisks indicate significant differences (p<.05) with

respect to the baseline and the minus sign ‘-‘ indicates a decrease of the proportion of

fixation with respect to the baseline.

Affirmative_MC Negative_MC Affirmative_O Negative_O

200-300 -.0033 -.0175 -.0067 .0062

300-400 .0358* -.0015 -.0211* - .0047

400-500 .1343* .0644* -.0501* -.0294*

500-600 .2625* .1621* -.0897* -.0597*

600-700 .3780* .2349* -.1222* -.0791*

700-800 .4484* .2707* -.1378* -.0879*

800-900 .4734* .2833* -.1398* -.0908*

900-1000 .4524* .2846* -.1391* -.0944*

1000-1100 .4388* .2759* -.1417* -.0915*

1100-1200 .4011* .2147* -.1372* -.0869*

1200-1300 .3849* .2147* -.1323* -.0764*

1300-1400 .3551* .1988* -.1260* -.0747*

1400-1500 .3139* .1894* -.1189* -.0691*

To sum up, Experiment 2 showed the same pattern as the one observed in

Experiment 1 for the multary context. Therefore, it must have been the availability of

the actual situation and not the verbal context that modulated the shift toward the actual

situation (or alternatives). It was found that people kept their visual attention on the

Mentioned color when the actual situation was not available, regardless of whether a

verbal context was presented or not. This finding is important, because many studies

have shown that negation is facilitated by context or pragmatics (Dale & Duran, 2011;


80

Nieuwland & Kuperberg, 2008; Tian et al., 2010). However, the prior presentation of

the dimension (i.e. the color) or of the negated and the actual situation in unspecified

way (i.e. the figure could be red or green or blue or yellow) does not seem to facilitate

negation as some authors have claimed (see Glenberg et al., 1999; Lüdtke & Kaup,

2006), unless this information specifies the negated situation or the actual situation,

such as is the case for the binary context.

We infer from our results that although negation is processed in a qualitatively

similar way to affirmation, a quantitative difference emerges. For example, when we

compared affirmative and negative sentences, we observed an increase in fixations on

the Mentioned color that was significantly higher for affirmative sentences (13%) than

for negative sentences (7%) starting at 400 ms (t(28)=3.116; p=.004). This also occurred

for the multary condition in Experiment 1: the increase in attention on the Mentioned

color was 11% for affirmatives and 5% for negatives starting at 400 ms (t(30)=2.160,

p=.039). This result could indicate that even when affirmative and negative sentences

are processed in a similar way in those conditions (in both cases people focused on the

Mentioned color), the proportion of attention to the Mentioned color is higher for

affirmative sentences than for negative sentences. The higher fixation on the Mentioned

color for affirmative sentences (16%) as compared to negative sentences (4%) was also

observed for the binary condition in Experiment 1 starting at 400 ms (t(30)=4.058,

p<.001).


81

6.5. Experiment 3

The previous experiments support the idea that people focus on the negated situation

both when understanding negation in a multary context (Experiment 1) and when no

context is provided (Experiment 2). However, as we used a recognition task (with no

deep comprehension demands) in these experiments, it might be argued that the

attention to the mentioned color might be due to a lack of full comprehension of the

sentences. Of course, this hypothesis would hardly explain the effects obtained in our

binary conditions. However, the goal of Experiment 3 was to test whether the

deployment of visual attention for isolated negative sentences using a verification task

would reproduce the pattern observed in the previous experiment for isolated negative

sentences using a recognition task. If so, this would disprove the aforementioned

alternative explanation, while lending additional support to our hypothesis. To that end,

we presented affirmative (e.g., the figure is red) and negative sentences (e.g., the figure

is not red) without any previous verbal context while a picture with four colored figures

(e.g., red, blue, green, and yellow) was shown on the screen. We predicted an increase

in the proportion of fixations on figures of the Mentioned color in both affirmative and

negative sentences, accompanied in both cases by a decrease in fixations on the

Alternative colors.


82

6.5.1. Method




Materials and procedure. The instructions and procedure were the same as in

Experiment 2. The only difference here was that participants were asked to complete a

verification task (e.g., could the figure be red?) instead of a recognition task (see Figure

4).

Figure 4. Procedure of Experiment 3: Verification task (the sentences have been

translating from the Spanish).


83

6.5.2. Results and Discussion

Behavioral data. Five participants were eliminated from the analysis as their data were

more than 2.5 standard deviations from the mean. The results showed that the

percentage of accurate responses was lower for negative sentences (80%) than for

affirmatives (92%; F(1,25)=37.306, p<.001, η2=.599). Also, the time that participants

took to read the comprehension question and answer it was longer for negative

sentences (1562(354) ms) than for affirmatives (1456(287) ms; F(1,25)=10.067, p=.004,

η2=.287).

Figure 5. Temporal course of the Mentioned color and Other colors for affirmative

(left) and negative sentences (right) without verbal context (verification task). The onset

of the critical word (the color word mentioned in the affirmative and negative sentence)

is represented by 0 on the horizontal axis. Error bars represent 95% confidence intervals

by subjects such that no overlap between conditions indicates a significant difference.

Eye movement data. The procedure for analyzing the eye movement data was similar to

that used in Experiment 1. Figure 5 shows the increase in fixation probabilities on the

Mentioned color that was observed for affirmative and negative sentences; however, the


84

proportion of fixation is lower for negatives than for affirmatives. The lower level of

attention on the Mentioned colors for negatives as compared to affirmatives is a stable

pattern that is observed across all contexts.

Table 4 shows the mean fixation probabilities of each time region with respect to

the baseline for both Mentioned color and Other color figures. For negative sentences, it

is observed that participant fixations increased for the figures of the Mentioned color

(t(25)=3.462, p=.002) and decreased for the Other colors (t(25)= 2.720, p=.012) starting

at 400 ms. The same pattern was observed for affirmatives, but the increase with respect

the baseline for the Mentioned color (t(25)=3.277, p=.003) and the decrease for the

Other colors (t(25)= -2.375, p=.026) started at 300 ms.


the baseline for the Mentioned color (MC) and Others (O) for affirmative and negative

sentences without verbal context. Asterisks indicate significant differences (p<.05) with

respect to the baseline and the minus sign ‘-‘ indicates a decrease of the proportion of

fixation with respect to the baseline.

Affirmative_MW Negative_MW Affirmative_O Negative_O

200-300 .0058 -.0016 -.0053 -.0073

300-400 .0426* .0115 -.0167* -.0143

400-500 .1508* .0905* -.0395* -.0323*

500-600 .2906* .2006* -.0776* -.0576*

600-700 .4226* .2934* -.0993* -.0671*

700-800 .5339* .3248* -.1094* -.0576*

800-900 .5492* .3046* -.1086* -.0445

900-1000 .5450* .2741* -.1047* -.0362

1000-1100 .5328* .2435* -.1066* -.0337

1100-1200 .5050* .2142* -.1026* -.0273

1200-1300 .5041* .1712* -.0997* -.0154

1300-1400 .4802* .1321* -.0981* -.0072

1400-1500 .4689* .1013* -.0988* .0012


85

6.6. General discussion

Two-step theory has claimed that negation cannot be represented explicitly, and that the

only way to comprehend negated sentences (e.g., the door is not open) is by means of a

shift of attention from the simulation of the negated situation (e.g., an open door, or in

our case the mentioned color) toward the simulation of the actual situation (e.g., a

closed door, or in our case the alternative; Kaup et al., 2006). This form of processing

negation fits well with the notion of a perceptual simulation (Barsalou, 1999), and our

results confirm that the participants tend to do that whenever possible. Mental model

theory also claims that most representations are perceptual-motor simulations or iconic.

However, it also allows for the occasional use of symbolic representations and, by

extension, the idea that negation could be represented explicitly. This means that

individuals should be able to retain the negated situation in their minds in order to

understand negation (Khemlani et al., 2012). Both two-step and mental model theory

share the same main assumptions; the essential difference between the two is that while

the former claims that people always change to the actual situation (or alternative), the

latter also supports the possibility that people might retain the negated situation (or

mentioned word).

The present study investigated, over three experiments, the time course of

attention shifting to the alternative color in the comprehension of negative sentences.

We found that participants do shift their attention to the alternative whenever possible,

but they also are able to retain the negated situation, as predicted by mental model

theory. In Experiment 1, we presented affirmative and negative sentences in binary and

multary contexts while participants viewed four different colors on the screen. The


86

results showed that people shifted their attention to the Alternative color starting 900 ms

after hearing negative sentences in a binary context, while they looked at the Mentioned

color the whole time in a multary context. In Experiment 2, we presented affirmative

and negative sentences in isolation (i.e. without a context), and the results replicated

those observed for the multary context in Experiment 1. As our participants had

demonstrated their understanding of the negative sentences, they must have retained the

Mentioned color, applying a symbolic negative operator to it (Giora, 2006; Khemlani et

al., 2012; Schul, 2011). This idea was confirmed in Experiment 3, where we used a

verification task to ensure participants’ full understanding of the sentences and obtained

the same results as those observed in Experiment 2 and in the multary context in

Experiment 1. This would therefore appear to indicate that the negation was also

understood in Experiments 1 and 2, even though only a recognition task was used. In

addition, it is important to consider the stable pattern observed in the understanding of

negation; individuals increased their attention to the negated situation starting at 400 ms

in all experiments. The N400 component is related to semantic features in event-related

potentials (Kutas & Federmeier, 2011), and future research should examine this possible

relation using co-registration.

The act of retaining the negated situation to understand negation, as evidenced

by the present findings, is opposed to the mandatory view of two-step theory, which

predicts that individuals will always understand negation through the actual situation

(e.g., representing the door is not open by a closed door). However, the results of all

three experiments presented here corroborate the claim that although people will prefer

to change the negated model for the affirmative model (or alternative) in a binary

context and a sensorimotor representation of negation is therefore possible, there are


87

cases (e.g., multary contexts) in which the negative assertion is not informative about

the actual situation and many alternatives are therefore available. It would appear that in

such cases, people might retain the negated situation and represent the negated operator

symbolically (Clark & Chase, 1972; Giora, 2006; Khemlani et al., 2012; Mayo, Schul,

& Burnstein, 2004; Schul, 2011). It seems then that while the cognitive system tends to

cancel a negated model by an affirmative model (or alternative) in binary contexts, it

would prefer to retain the negated model instead of many different affirmative models

(or alternatives) which could overload the memory in multary contexts. This would

happen as consequence of the limitations of working memory: multiple models can

overload its processing capacity and lead to errors in which reasoners fail to consider

some models of the premises. As drawing Johnson-Laird (2001), the fewer the number

of models needed for an inference, the easier the inference should be by the effect of

limit memory. Our results are also consistent with those of certain studies that, while

not opposing the embodiment theory, have identified some exceptions (Anderson et al.,

2010). For example, Tian and collaborators (2010) presented affirmative and negative

sentences that were either cleft (‘it was Jane who didn’t cook the spaghetti’) or non-cleft

(‘Jane didn’t cook the spaghetti’), with a matching or mismatching picture appearing

250 ms later. The participants were to indicate whether the object in the picture had

been mentioned in the preceding sentence or not. The results showed an interaction

between the type of sentences (cleft or non-cleft) and the matching condition. That is,

after a non-cleft negated sentence, responses were faster when the image mismatched

than when it matched, a result that supports the two-step simulation. However,

participants were faster in response to matching images after hearing cleft negated

sentences. This result poses problems for two-step processing (Kaup et al., 2006, 2007).


88

One result that has been consistent in the three experiments was the Mentioned

word is less attended visually for negative sentences than affirmatives. A question that

arisen is whether this fact would be related to the longer time that was required to

answer the recognition or verification task after listening to negative sentences compare

to affirmative sentences, result that is consistent in literature (see Carpenter & Just,

1975; Carpenter et al., 1999; Clark & Chase, 1972; Trabasso, Rollins, Shaughnessy,

1971; Wason & Johnson-Laird, 1972; Wason & Jones, 1963). Also, the fixation on the

Mentioned color could be related to the literature on recall. For instance, the

embodiment theory claims that negative concepts are less accessible (through recall)

than affirmative concepts, because the negated situation is replaced by the actual

situation (Kaup, 2001). On the other hand, propositional theory holds that negation is an

explicitly represented operator that takes a whole proposition in its scope. As the

negation operator encapsulates the negated concept, it is less accessible (Fillenbaum,

1966; Hasson & Glucksberg 2006; Lea & Mulligan, 2002; MacDonald & Just, 1989).

This latter point of view fits better with our results, because the negated situations (or

the Mentioned color) received less attention than the affirmatives in both the binary and

multary contexts, while an inhibition of the negated situation due to the change toward

the actual situation only happened in the binary context. In sum, the lower amount of

visual attention paid to the Mentioned word for negative sentences could be related to

the fact that the negative concepts are harder to process and recall.

Finally, it is important to consider whether the results of this study (which uses

exclusively perceptual features, i.e. colors) could be generalized to include more

abstract concepts. In our view, a shift of attention toward the actual situation (or

alternative) such as that tested in our study depends more on the availability of the


89

actual situation than on the format used to represent the concepts. As the reader can

corroborate in any association corpus, such as the Spanish free-association norms

(Fernández et al., 2004), the two words of binary predicates are highly associated in the

case of both perceptual and abstract concepts; this association should facilitate the shift

of attention to the alternative, which will be modulated by the accesibility of the actual

situation regardless of the format used to represent the negated argument (e.g., the

figure is not red or the door is not open). Also, literature has shown that the shift of

attention to the alternative can be modulated by context. In our experiments, the context

was logically dichotomized by adding disjunctions, and the binary context showed

similar results to those obtained by Kaup et al. (2006), while the multary context

showed results that we would expect to see when the actual situation is not available.

We found that the multary condition gave results that were similar in the three

experiments, whether the verbal context was explicit or not, therefore the availability of

the actual situation would appear to be more important than the verbal context for

shifting attention toward the actual situation (or alternative). In sum, the representation

of negation (the negated situation or the actual situation) depends on the availability of

the actual situation, and when this is unavailable, the mental representation of the

sentence calls for symbolic tags.

6.7. Conclusion

In conclusion, this study has shown that individuals are able to retain the negated

concept and consequently, they should be able to represent the negation operator.

However, when the alternative concept is available, they prefer to shift attention to the


90

analogically representable concept. This result supports a theory that assumes that a

symbolic representation of negation is possible (e.g., the mental model theory; Johnson-

Laird, 1983).

Visual concepts impede negation

91

7. Visual concepts impede negation

7. 1. Abstract

Many studies have showed the advantage of processing visual concepts over non-

visuals. The present paper reports the case of negation in which, presumably, imagery

could slow down processing. Negation reverses the truth value of an argument from

false to true or vice versa. Propositions and not images are true or false. Consequently,

an image cannot be negated directly. In contrast, negation can be readily attached to a

linguistic representation as a syntactic operator. This leads to a paradoxical hypothesis:

despite the advantage of visual words for general processing, the negation of arguments

involving them (related to the representation of an image) would be harder than

negation involving non-visual words. Two experiments support this hypothesis by

showing that sentences with a previously negated visual argument took longer to be

read than sentences with non-visual arguments.

7. 2. Introduction

There is growing evidence supporting the idea that iconic (analogical) representations

are crucial in understanding language. This means, for instance, that individuals tend to

construct an image of a red figure in order to understand the sentence: the figure is red

(Barsalou, 1999; 2005; 2008; Glenberg, Meyer, & Lindem, 1987; Johnson-Laird, 1983;

Zwaan & Radvansky, 1998). This evidence connects with the classical concreteness

effect: concrete concepts are processed more quickly and accurately than abstract


92

concepts in a variety of tasks, such as word recognition, lexical decision, recall,

problem-solving, and reasoning (for a review, see Denis, 1989). Indeed, this effect has

been related to an iconic representation (an image code in the words of Paivio, 1991,

2013) that could be implicated in the processing of concrete concepts but not of abstract

concepts. The advantage of concrete concepts over abstract concepts could be related to

the greater processing demands needed to construct images (cf. Johnson-Laird &

Bethell-Fox, 1978). This type of representation is more structured and elaborated than

verbal representation, and consequently leads to a richer and deeper semantic processing

(cf. Craik & Tulving, 1975). Furthermore, this dual coding theory (Paivio, 1991) has

found support in recent neuroimaging studies showing that the neural representation of

abstract concepts relies more heavily on the verbal system, while concrete concept

representation involves more mental imagery and relies more heavily on the perceptual

system (see Wang et al., 2010 for a meta-analysis).

In sum, the role of imagery is currently considered crucial in language

comprehension. However, by their very nature, some components of natural language

cannot be represented iconically. One significant example of this is negation. Negation

is a syntactic operator that takes a proposition and reverses its truth value. In other

words, if the proposition A is false (e.g., Steve Jobs is alive), then Not A is necessarily

true (e.g. Steve Jobs is not alive) and vice versa; this is an analysis that goes back to

Aristotle (1984). Propositions are the smallest units of knowledge that can be true or

false. Negation reverses the truth value of arguments from false to true or vice versa

such as propositions or sets of propositions, but cannot apply directly to icons or

images, as they are not true or false arguments. However, the mental model theory

considers that negations can be stored as ‘mental footnotes’ (see Johnson-Laird, 2001).


93

For example, ¬RED denotes a model of the possibility in which a figure is not red. But

people soon lose track of these footnotes because they are hard to remember. There is

no such thing as an image of falsity. From the meaning of negation and image, it could

be inferred a paradoxical situation: while concrete concepts will generally be easier to

process, the negation of arguments involving abstract concepts, which are related to the

verbal system, would be easier to process than the negation of arguments involving

concrete concepts, which are related to the perceptual system or imagery.

There are no studies that have focused on this novel prediction, at least to our

knowledge, but if it is true, the negation of arguments involving visual words should be

slower than negation involving non-visual words. To test this, we carried out two

experiments using a subtle methodology. The goal was to present the same target for

both conditions to avoid possible lexical and sub-lexical effects, among others. To

achieve this, the experimental texts in Experiment 1 consisted of a sentence formed by

an initial conjunctive phrase connecting a visual and a non-visual word. We alternated

between negation of the argument involving the visual word: the boy was brave and he

was not asleep and negation of the non-visual argument: the boy was awake and he was

not cowardly. The next sentence (the target) consisted of a similar conjunctive phrase

but with a replacement of the previously negated word with its contrary. The resulting

sentence contained the same words for the visual condition: the boy was brave and he

was awake and the non-visual condition: the boy was awake and he was brave. The

dependent variable was the time that participants took to read this target sentence. The

predicted result was that the participants would take longer to read the target sentences

after the arguments where the visual words were negated.


94

In Experiment 1, the participants had to change from a negated situation (e.g.,

the boy was not asleep) to a situation with the same meaning but using the contrary term

(e.g., the boy was awake). This processing of negation would be related to cancellation

of the negated concept (asleep). To rule out the possibility that our results were a

consequence of the cancellation of concepts rather than the use of negation of each type

of argument, we designed Experiment 2, in which the negative concepts were preserved

in the target sentences. Here, we presented a sentence formed by an initial conjunctive

phrase connecting a visual and non-visual word, one of which was presented in negated

form (e.g., John said that the boy was brave and he was not asleep). The next sentence

established whether John was right or wrong (50% each), and finally the target sentence

was presented (e.g., the boy was brave and he was asleep). As seen, the last sentence

repeated the same words from the first one (brave and asleep) and was the same across

conditions. The predicted result was the same as for Experiment 1.

7. 3. Experiment 1

The aim of Experiment 1 was to test whether the negation of arguments involving visual

words would be slower than the negation of arguments with non-visual words.

7.3.1. Method

Participants. Eighty-two native Spanish speakers from the University of La Laguna,

Tenerife (Spain), participated in the experiment in exchange for course credits.


95

Material and Procedure. Two normative studies were carried out before the

experimental study. The goal of the first normative study was to select the material,

which consisted of visual and non-visual words with a clear contrary. We presented 80

sentences (20 pairs of visual and non-visual words and their contraries (20*4=80)).

Seventy-six students of the University of La Laguna (64 females; mean age: 22 years)

had to write the contrary of each word and estimate the degree of visualization in the

choice using a Likert scale from 1 to 5. For example, the boy was asleep. The boy was…

The underlined words were obtained from the Spanish free-association norms

(Fernández et al., 2004). The selection criterion for visual and non-visual words was

that they must have a clear contrary, i.e., the percentage of agreement about the contrary

must be above 90%. Following this criterion, half of the items were eliminated, leaving

40 words for use in the experimental study. Visual (20) and non-visual (20) words were

equated for word frequency, number of syllables, and letters (see Table 1). We used

BPAL to determine the words’ characteristics (Davis & Perea, 2005). There was also no

difference between visual and non-visual words with respect to the percentage of

participants’ agreement on the contrary. The only difference between them was the

degree of visualization (t(75)=14.157, p<.001; see Table 1).

Table 1. Mean values for characteristics of stimuli.

Experiment 1 Experiment 2

Visual Non-visual Visual Non-visual

Frequency 1.46 1.65 1.63 1.44

Number of syllables 3 3 3 3

Number of letters 7.10 6.60 6.22 6.67

Agreement on the contrary 98% 97% 98% 94%

Degree of visualization 4.12 2.63 4.29 2.73


96

The goal of the second normative study was to reproduce with our material the

typical concreteness effect observed in lexical decision tasks: faster decision times for

visual than non-visual words. Fifty-three native Spanish speakers from the University of

La Laguna, Tenerife (Spain), participated in the experiment study in exchange for

course credits. We presented the 80 words (40 visual and 40 non-visual words) used in

Experiments 1 and 2 and 80 pseudowords that were created from these words, which

thus kept the same properties. Each trial started with a fixation crosshair for 400 ms,

followed by the string that remained on the screen for 2000 ms or until a response was

given. Finally, a black screen appeared with the indication ‘please, press the SPACE bar

to continue’. The experiment started with six practice trials and all stimuli were

presented in a random order. To indicate whether or not a string was a Spanish word,

participants were asked to position their left and right index fingers on two response

buttons marked yes/no. The experiment lasted approximately 5-10 minutes. The

participants completed the experiment in an individual cubicle and the instructions and

trials were presented via the program E-PRIME 2.0 in a PC with CRT screen. An

ANOVA comparing lexical decision latencies across words (663 ms; sd=83) and

pseudowords (788 ms; sd= 112) indicated a significant lexical effect (F(1,52)=179.359,

p<.001): words were identified faster than pseudowords. In addition, lexical decisions

were faster for visual words (656 ms; sd=87) than for non-visual words (670; sd=83;

(F(1,52)=6.468, p=.014). This result showed the classical concreteness effect and the

well-known advantage of visual words in lexical decision tasks.

Based on the results of the first normative study, we presented 40 experimental

trials preceded by four practice trials. Also, 32 filler sentences were presented. Each

trial had two sentences. The first presented the description of either a person or an


97

object through two words, one visual and one non-visual, one of which was negated.

For example: the boy was awake and he was not cowardly. Participants had to read the

sentence and press the button as soon as possible after reading it. Then a second

sentence with similar meaning appeared, but in this case the negated word was replaced

by its contrary (e.g., the boy was awake and he was brave). Half of the sentences

negated the arguments involving the visual word (e.g., the boy was brave and he was

not asleep/the boy was brave and he was awake) and half negated the non-visual

argument. The second, target sentence was similar for both visual and non-visual

conditions (only the order was altered; see Table 2). The predicted result was that the

response to the target sentence after the negation of arguments with visual words would

be slower than with non-visual words. The only task given the subjects was to read the

sentences and press the button as soon as possible. Some comprehension questions also

appeared to check that people were actually reading the sentences. The participants

completed the experiment in an individual cubicle and the instructions and trials were

presented to them via the program Presentation 12.1 in a PC with CRT screen.


98

Table 2. Examples of experimental sentences of Experiments 1 and 2

Visual Condition Non-visual Condition

Exp 1 The boy was brave and he was not

asleep.

The boy was brave and he was

awake.

The boy was awake and he was not

cowardly.

The boy was awake and he was brave.

Exp2 John said that the boy was brave and

he was not asleep.

John was right.


awake.

John said that the boy was awake and

he was not cowardly.

John was right.


John said that the boy was brave and

he was not awake.

John was wrong.


awake.

John said that the boy was awake and

he was not brave.

John was wrong.


7.3.2. Results and discussion

We removed two subjects whose reaction times were more than 2.5 standard deviations

from the mean, thus we analyzed 80 participants. 88% of the comprehension questions

were responded to correctly, thus indicating that participants were reading and

comprehending the sentences. We found that the visual target sentences (1734 ms;

sd=365) took longer to read than the non-visual target sentences (1693 ms; sd=341), and

these differences were significant (t(79)=2.295, p=.024). Fifty-two participants showed

this pattern.


99

7. 4. Experiment 2

Experiment 1 showed that the negation of arguments involving visual words took longer

to read than those involving non-visual words. This result is likely due to the fact that

negation cannot easily apply to images and since visual words have this kind of

representation, this could slow down the processing of negation. However, there is

another possibility. It has been shown that in negation with contraries – the material that

we used in Experiment 1 – the negated concept is cancelled by an alternative; that is to

say, individuals understand the boy was not asleep to mean he was awake (Kaup,

Lüdtke, & Zwaan, 2006). Also, it is well documented that visual words have two codes:

image and verbal, whereas non-visual words have only one code: verbal (Paivio, 1983;

1986; 1991; 2007; 2013). The advantage enjoyed by visual words in many tasks is

related to these two codes. This means that the negation of arguments involving visual

words would be more difficult than negation involving non-visual words by the effect of

cancellation of two codes instead of only one. To examine this alternative hypothesis,

we designed Experiment 2, similar to Experiment 1, but where we presented the same

words in the first and second sentences so that individuals would retain the negated

concept instead changing to the alternative. If the results of Experiment 2 were similar

to Experiment 1, this would corroborate the effect of negation on visual words and not

to the cancellation.


100

7.4.1. Method

Participants. Ninety-two native Spanish speakers from the University of La Laguna,

Tenerife (Spain), participated in the experiment in exchange for course credits.

Material and Procedure. We took 80 words from the first normative study, including 40

visual and 40 non-visual words. We added more words in this experiment for two

reasons: 1) to strengthen our data and 2) because the percentage of agreement about the

contrary was not important in this experiment, given people had to retain the negated

word and not change to the alternative. In the case of Experiment 2, the percentage of

agreement on the contrary was higher for visual than for non-visual words (98%/ 94%;

t(78)=3.055, p=.003) and there were differences in the degree of visualization

(4.29/2.73; t(78)=17.529, p<.001). The words were equated for frequency, number of

syllables, and letters (see Table 1).

Eighty trials were presented to participants. Each trial started with the

description of a person, in which either a visual argument (e.g., John said that the boy

was brave and he was not asleep) or a non-visual argument (e.g., John said that the boy

was awake and he was not cowardly) was negated. The next sentence established

whether the description was right (e.g., John was right) or wrong (e.g., John was

wrong). The trial finished with the target sentence, which was similar for all conditions

but with the order altered. In sum, four conditions were created (see Table 2). In the first

two conditions, people had to retain the negated concept: 1) when negation involves a

visual word and the information is wrong (e.g., John said that the boy was brave and he

was not awake. John was wrong. The boy was brave and he was awake); and 2) when


101

negation involves a non-visual word and the information is wrong (e.g., John said that

the boy was awake and he was not brave. John was wrong. The boy was awake and he

was brave). The next conditions are similar to Experiment 1, people had to change to

the alternative: 3) when negation involves a visual word and the information is right

(e.g., John said that the boy was brave and he was not asleep. John was right. The boy

was brave and he was awake); and 4) when negation involves a non-visual word and the

information is right (e.g., John said that the boy was awake and he was not cowardly.

John was right. The boy was awake and he was brave). Each sentence appeared

successively according to the reader’s own pace. Also, 34 filler sentences were

presented. The only task given to subjects was to read the sentences and press the button

as soon as possible. Some comprehension questions also appeared to check that people

were actually reading the sentences. The participants completed the experiment in an

individual cubicle and the instructions and trials were presented to them via the program

Presentation 12.1 in a PC with CRT screen.

7.4.2. Results and discussion

We removed ten subjects whose reaction times were more than 2.5 standard deviations

from the mean, thus we analyzed 82 participants. 91% of the comprehension questions

were responded to correctly, thus indicating that participants were reading and

comprehending the sentences. There was interaction between degree of visualization of

the argument that was negated in the first sentence (visual and non-visual) and the

message of the second sentence, wrong or right (F(1,81)=4.612, p=.035). There were no

main effects. Post hoc t-tests revealed that participants took longer to read the sentence


102

that appeared after the wrong description with negation of a visual argument (e.g., John

said that the boy was brave and he was not awake. John was wrong. The boy was brave

and he was awake; 1933 ms; sd=456) than the sentence that appeared after the wrong

description with negation of a non-visual argument (e.g., John said that the boy was

awake and he was not cowardly. John was wrong. The boy was awake and he was

brave; 1858 ms; sd=437); t(81)=2.542, p=.013). This finding rejects the possibility that

this effect is due to a cancellation of the negated concept. In other words, as a linguistic

operator, negation would operate better with arguments involving non-visual words

(verbal representations) than with visual words. The iconic representation related to

visual words seems to slow down the processing of negation.

There was no difference between the two sentences that appeared after the right

description for the visual condition (e.g., John said that the boy was brave and he was

not asleep. John was right. The boy was brave and he was awake; 1853 ms; sd=418)

and the non-visual condition (e.g., John said that the boy was awake and he was not

cowardly. John was right. The boy was awake and he was brave; 1859 ms; sd=436;

t(81)=-.209, p=.835). These two conditions were similar to those presented in

Experiment 1; that is to say, individuals needed to change to the alternative in the target

sentence. However, we found no differences in Experiment 2 similar to those found in

Experiment 1. One possible reason would be that the difference between the visual and

non-visual conditions found in Experiment 1 is small (41 ms), and it could vanish with

the introduction of the second sentence (e.g., John was right) in Experiment 2.

However, the second sentence: John was wrong introduces another negation and it can

make comprehension more difficult and the studied effect is maintained as described

above.


103


Negation is a syntactic operator that takes an argument and reverses its truth value. A

proposition can be true or false. If a proposition is true, its negation is false and vice

versa. However, images cannot be true or false, and as result, negation cannot apply

directly to them. From this definition of negation, it could be inferred that the negation

of arguments involving visual words (related to imagery representations) could be

slower than for arguments involving non-visual words. The results of Experiments 1

and 2 corroborated this novel hypothesis. Sentences that appeared after the negation of

an argument involving visual words took longer to be read than those appearing after

non-visual words, even though visual words took less time to read than non-visual

words in a lexical decision task. Both results constitute converging evidence of a

different representation of visual and non-visual words.

These results fit well with theories that distinguish between a visual code and a

non-visual code, such as the dual coding theory (Paivio, 1983) or the mental model

theory (Johnson-Laird, 1983). Also, Barsalou (2008) pointed out that the simulation

system is closely integrated with the linguistic system. From all these points of view,

the role of imagery is crucial in language, memory, problem-solving and reasoning in

order to improve performance, although this advantage could be reversed in certain

cases, such as negation.

Finally, it is important to note that our results may be not restricted to negation.

Knauff and Johnson-Laird (2002) found that visual relations slowed down the process

of reasoning (relational inference and conditional reasoning) in comparison with control

relations, visuospatial and spatial relations. The authors concluded that visual images


104

are not critical for deductive reasoning and may even interfere with the process, whereas

spatial representations help individuals to reason deductively. The authors reported

studies that have showed an advantage for visual representation; however it seems that

the material used in those studies has more spatial than visual properties (cf. De Soto,

London, & Handel, 1965). Also, several studies have failed to detect any effect of

imageability on reasoning (cf. Sternberg, 1980). Those results that have been

corroborating in neuroimaging studies showing that only visual relations elicited

additional activity in visual context while all types of relations evoked activity in the

parietal cortex related to reasoning (Knauff, Fangmeier, Ruff, & Johnson-Laird, 2003).

This hypothesis has been tested with participants who were blind from birth, and they

were not affected by the visual-impedance effect (Knauff & May, 2006).

Taken together, we could conclude that when image representations yields

information relevant to a processing, as it does with mental rotation (Shepard & Cooper,

1982) then it would improve the processing and performance. But if visual images

containing details that are irrelevant to a processing should impede and takes longer the

processing. It leads to a more general and remarkable conclusion: negation and certain

types of reasoning must apply to the concepts related to abstraction and not to the image

related to figuration and concreteness, details that may not be relevant for those

processing.

Inconsistencies make negation plausible

105

8. Inconsistencies make negation plausible: Evidence from the VWP

8.1. Abstract

Communicative language usually refers to what is true or what has happened.

Consequently, negation is typically harder to understand than affirmation. However,

when context makes negation plausible it could be as easy as affirmation. One example

is when the negative sentence denies a false belief. We explored this hypothesis using

the visual world paradigm. In the present study, we presented three types of context

followed by affirmative or negative sentences while presenting images of the affirmed

or denied entities. In a neutral context the participants looked at the affirmed entities

prior to the denied entities. This effect was magnified when the context corresponded to

a contextually true belief. However, people looked at the object that corresponded to the

negation within the same time frame as they looked at the object that corresponded to

the affirmation when the sentence referred to a contextually false belief. Our results

suggest that negation is easier to understand within a context that presents a false

argument.

8.2. Introduction

The comprehension of language is context-dependent: its content depends not only on

the syntactic and semantic properties of the types of expressions used, but also on facts

about the situation in which the expressions are used (Stalnaker, 1998). Negative

sentences do not point to the actual situation but to what is not the case. As a


106

consequence, in their comprehension we should figure out what the speaker is referring

to, and pragmatics becomes crucial. If someone tells us that their car is not red there

should have been a reason to presume (or speculate) that it is red. Otherwise the utterer

would have referred to the actual color of the car. In fact, individuals seem to use

affirmation to communicate as default, but negation is often used in some specific

contexts, and outwith these contexts negation is difficult to understand (Khemlani,

Orenes, & Johnson-Laird, 2012).

The comprehension of negation is relatively easy in a binary context (also called

complementary) because the actual situation is available. For instance, if people are

speaking about the United States elections in 2012 and they say: ‘eventually Romney did

not win the election’, hearers are likely to understand that Obama won because only one

of them could win, even though many parties were involved. It is assumed that the

comprehension of negative sentences with binary predicates such as the above example

would be accomplished through two representational steps (Kaup, Lüdtke & Zwaan,

2006). The first step is represented via a perceptual simulation of the negated situation

that corresponds to its affirmative counterpart (e.g., Romney won the election); in a

second step, this perceptual simulation would be changed to the actual situation implied

by the negative (e.g., Obama won the election). The aim of the present study was to

explore how this change of attention from the negated situation toward the actual

situation is modulated by context.

Literature on negation has reported that negative sentences are more difficult to

comprehend than their corresponding affirmatives: people take longer to process them

and they make more mistakes (see Carpenter & Just, 1975; Clark & Chase, 1972; Mayo,

Schul, & Burnstein, 2004; Trabasso, Rollins, & Shaughnessy, 1971; Wason & Johnson-


107

Laird, 1972; Wason & Jones, 1963). This finding would indicate that negation adds

semantic richness to the argument denied (Miller, 1962). However, recently many

studies have also shown that when negation is presented in an adequate context, it could

be similar to affirmation (Dale & Duran, 2011; Givon, 1978; Johnson-Laird & Tridgell,

1972; Nieuwland & Kuperberg, 2008; Strawson, 1952; Tian, Breheny, & Ferguson,

2010; Wason, 1972). Thus, it is relevant to study the contextual factors that make the

unfolding processing of negation easier to understand.

Wason (1965) was the first psychologist who showed how pragmatics could

benefit the comprehension of negation. This author presented seven red circles and one

blue circle while participants were instructed to describe the stimulus aloud. The results

showed that participants took longer when using negation to describe the red circles

compared to the corresponding affirmative, while this complexity of negation was less

pronounced when using negation to describe the blue circle. This finding supports the

exceptionality hypothesis which claims that the effect of negation is reduced when used

to refer to a distinctive or unusual attribute. Glenberg and collaborators (1999) found

that people took longer to read negative sentences rather than affirmative sentences

(e.g., the couch (was/was not) black) into a non-supportive context which presented a

different attribute dimension to the affirmative or negative sentences (e.g., She wasn´t

sure what kind of material she wanted the couch to be made of), whereas they read

similarly both types of sentences into a supportive context which highlighted the

relevancy of the attribute dimension that was referred to the affirmative and negative

sentences (e.g., she wasn’t sure if a darkly colored couch would look the best or a

lighter color). However, Lüdtke and Kaup (2006) pointed out that a context that

explicitly mentions the negated concept (e.g., whether the water would be warm or


108

whether the water would be warm or cold) is a better context for the processing of a

negative sentence (e.g., the water was not warm) than a context that merely activates the

relevant attribute dimension (e.g., what the water would be like). They also showed that

negation (e.g., The T-shirt was not dirty) is as easy as affirmation (e.g., The T-shirt was

clean) when the negated concept was highly plausible (e.g., that a boy´s T-shirt is dirty

after he played outside in the backyard). It is interesting to note that all these studies

described above used binary (or complementary) predicates, thus the fact that the actual

situation was available seems important to facilitating comprehension of negative

sentences (see Beltrán, Orenes, & Santamaría, 2008).

In the current study, we presented three different types of context followed by

affirmative and negative sentences while presenting images of the affirmed or denied

entities. As negation is focused on what is not the case, we predicted that a context that

presents the argument that is going to be negated first (inconsistent context) should

make negation easier to understand while a context that presents the actual situation

(consistent context) should make it harder to understand. An intermediate case would be

a neutral context. We explored this hypothesis using the visual world paradigm. Until

now, most studies of negation have used RT and ERP methodologies, but the visual

world paradigm presents some advantages. In a typical visual world task verbal and

visual inputs are presented simultaneously while the participants’ eye movements are

recorded. Eye movements provide an index of real time processing that most other

methodologies do not, and they are sensitive to subtle aspects of language, attention and

memory (Allopenna, Magnuson, & Tanenhaus, 1998; Duñabeitia et al, 2009; Rayner,

1998). From the literature, it is expected that when something is heard, it is processed

and attended to automatically. At the same time, if the object is visible, the eyes begin


109

to move towards the corresponding object (Cooper, 1974; Tanenhaus et al., 1995). In

other words, there is a correspondence between what is visually attended and what is

been processing (Eye-mind Hypothesis; Just & Carpenter, 1976). Also, this

methodology allows us to see the unfolding process without the intervention of a

researcher. That is, the images, related or not to the information that participants hear,

are on the screen the whole time, and participants look at them as a consequence of their

comprehension. In most other studies, images are presented after the verbal or written

information, so it is not possible to have an online measure of processing, but this is not

the case with the visual world paradigm.

8.3. Method

Participants. Fifty native Spanish speakers from the University of La Laguna, Tenerife

(Spain), participated in the experiment in exchange for course credits. All of them had

uncorrected vision or wore soft contact lenses or glasses.

Materials. Forty-eight experimental vignettes of simple events were heard. The first two

sentences per vignette described a general situation (e.g., Veronica needed a new car for

work. She wondered whether her dad could help her financially). The last sentence in

each vignette presented a context. The context could be consistent (e.g., She supposed

that her dad had enough savings), inconsistent (e.g., She supposed that her dad had

little savings) or neutral (e.g., her dad lived on the other side of town) with respect to

the target part of the story that consisted of an affirmative or a negative sentence (e.g.,

her dad was not poor).


110

Figure 1. Example of a display with two images, one corresponds to a rich man and

another to a poor man.

For each trial, a different display with two images appeared on the screen. For

example, an image of a rich man on the left and a poor man on the right (see Figure 1).

The position of each image was counterbalanced. The order of the materials was

randomized, and 12 versions of the full set of materials were prepared because each

context (consistent, inconsistent, and neutral) was combined with the two types of

sentences (affirmative and negative) and the two poles of the adjective contraries (e.g.,

poor-rich), so that only one of the 12 possible versions of each experimental item

occurred in each presentation (see Table 1). In total, there were 8 experimental trials in

each of six conditions: consistent-affirmative, consistent-negative, inconsistent-

affirmative, inconsistent-negative, neutral-affirmative, and neutral-negative. For all

trials, the target word was the adjective word mentioned in the last sentence of the story.

This target word established the onset from which the time course of fixations was

analyzed.


111

Table 1. Examples of experimental sentences

Veronica needed a new car for work. She wondered whether her dad could help her

financially.

Consistent-Affirmative: She supposed that her dad had little savings.

Her dad was poor. Version 1.

She supposed that her dad had enough savings.

Her dad was rich. Version 2.

Consistent-Negative: She supposed that her dad had enough savings.

Her dad was not poor. Version 3.

She supposed that her dad had little savings.

Her dad was not rich. Version 4.

Inconsistent-Affirmative: She supposed that her dad had enough savings.


She supposed that her dad had little savings.


Inconsistent-Negative: She supposed that her dad had little savings.


She supposed that her dad had enough savings.


Neutral-Affirmative: Her dad lived on the other side of town.


Her dad lived on the other side of town.


Neutral-Negative: Her dad lived on the other side of town.


Her dad lived on the other side of town.


Apparatus and Procedure. Participants’ eye movements were recorded at a rate of 500

Hz using an SR Research EyeLink II head-mounted eye-tracker connected to a 21-inch

color CRT for visual stimulus presentation. Procedures were implemented in SR

Research Experiment Builder. Calibration and validation procedures were carried out at

the beginning of the experiment and repeated several times per session. Trials started

with the presentation of a central fixation dot for drift correction while participants

listened to the general situation and the context (consistent, inconsistent, or neutral).

After that, a display with two images appeared for 2 seconds and then the story finished


112

with the presentation of an affirmative or negative sentence that was the target. The trial

concluded with the appearance of a written question (e.g. did Veronica need a new

car?) which participants had to answer by pressing either a “yes” or a “no” button.

There was a practice block of four trials before the experiment proper started. The entire

experiment lasted approximately 30 minutes.

8.4. Results

The eye-movement data generated by the EyeLink system were analyzed as follows.

First, bitmap templates were created for identifying regions of interest in each display

(e.g., a rich and a poor man). The object regions were defined in terms of rectangles

containing the relevant objects; fixations landing within the perimeters of these

rectangles were coded as fixations on the relevant objects. The output of the eye-tracker

included the x- and y-coordinates of participant fixations, which were converted into

region of interest codes using the templates. Fixations shorter than 80 ms were pooled

with preceding or following fixations if they were within 0.5 degrees of visual angle.

Times for blinks were added to the immediately preceding fixations. The analyzed time

period was from the onset of the target word to 1500 ms after the target word (as

established on a by-trial basis). This time window was chosen to guarantee there was

enough time to comprehend negations (e.g., Kaup et. al., 2006; Lüdtke et al., 2008).

This period was further divided into 50 ms time slots. For each time slot, the number of

fixations on each image was counted and converted into fixation probabilities obtained

from the proportion of one of them and the sum of both of them fixation proportions.


113

Figure 2 depicts probabilities of fixations on the target region of interest as a

function of time and context. The target region of interest or ‘the mentioned image’ was

the image that was literally mentioned. For example, poor man when the target word

was ‘poor’ or ‘not poor’. Be aware that when people heard ‘poor’, they increased their

attention on the poor man while when they heard ‘not poor’, they decreased their

attention on the mentioned image for attending the rich man. Remember that the

proportion of fixation on the mentioned image (e.g., the poor man) was computed by

counting, the proportion of fixations on the poor man relative to the sum of probability

of fixation on the poor man and the rich man. The sum of both proportions is 1. This

means that the decrease of one is the increase of another.

Figure 2.1 corresponds to the neutral context, where people heard a context that

was not related to the critical sentence (or target). For example, ‘Her dad lived on the

other side of town’. In this case the context does not say anything about the images that

are shown on the screen, therefore individuals look at both images equally often. When

participants listened to the affirmative sentence, e.g. ‘Her dad was poor’, fixation

probabilities on the mentioned image increased (e.g. the poor man) and decreased

during negative sentence: ‘Her dad was not poor’ on the mentioned image (e.g. the poor

man). The latter indicates that there was an increase of fixation probabilities on the

alternative image (e.g., the rich man). This simple effect of polarity (affirmative versus

negative) in neutral contexts started at around 500 ms after target word onset.

Importantly, before this point in time, there was no clear difference between affirmative

and negative sentences.


114

Figure 2.1. Probabilities of fixations on the (mentioned) target image over time,

separately for affirmative and negative sentences within neutral contexts. Before the

onset of the target word (t < 0), participants focused on both images about equally

frequently because the context was neutral. From about 500 ms after target word onset,

probabilities of fixations on the mentioned image started to increase for affirmative

sentences while they decreased for negative sentences. Error bars represent 95%

confidence intervals by subjects such that no overlap between conditions indicates a

significant difference.

Figure 2.2 shows the data for the inconsistent context condition, where

participants heard the critical affirmative or negative sentence following a context that

was inconsistent with what was mentioned in the critical sentence (e.g., She supposed

that her dad had enough savings -> Her dad was poor/not rich. OR She supposed that

her dad had little savings -> Her dad was rich/not poor). When the critical sentence

was inconsistent affirmative (e.g., Her dad was poor after She supposed that her dad

had enough savings), participants shifted their attention from the image not mentioned

in the critical sentence (rich man) toward the image mentioned in the critical sentence


115

(poor man). When the critical sentence was inconsistent negative (e.g., Her dad was not

poor after She supposed that her dad had little savings), they shifted their attention from

the image of the poor man (inferred from the context) toward the image of the rich man

(inferred from the target sentence). As can be seen, from ca. -500 ms to +550 ms

relative to the target word onset, the mentioned referent was more likely to be fixated in

negative than in affirmative sentences. This effect reversed from ca. 600 ms onwards.


separately for affirmative and negative sentences within inconsistent contexts. In the

case of negation, we observed that participants looked at the mentioned image before its

onset, and when it was negated, they decreased their attention on it and focused on the

alternative image. In the case of affirmation, we observed that participants looked at the

alternative image and then they changed toward the mentioned image when it was

heard. Error bars represent 95% confidence intervals by subjects such that no overlap

between conditions indicates a significant difference.

Figure 2.3 shows the data for the consistent context condition, where participants

heard a context (e.g., She supposed that her dad had enough savings OR She supposed


116

that her dad had little savings) that was consistent with the critical sentence (e.g., her

dad was rich/not poor OR her dad was poor/not rich). When the critical sentence was

affirmative (e.g., her dad was poor after She supposed that her dad had little savings),

individuals kept active the same concept (the poor man), the opposite happens for

negative sentence (e.g., Her dad was not poor after She supposed that her dad had

enough savings).


separately for affirmative and negative sentences within consistent contexts. In the

affirmative condition, probabilities of fixations on the mentioned image were reliably

above 50% across the entire time course, but there was a notable increase in those

probabilities from around 700 ms after the onset of the target word. In the negative

condition, the mentioned image was fixated reliably less than 50% of the time, but we

observed a slight increase in those probabilities when the critical word was heard

(peaking around 500 ms after critical word onset). Error bars represent 95% confidence

intervals by subjects such that no overlap between conditions indicates a significant

difference.


117

To explore the statistical significance of the observed pattern, mean fixation

probabilities were first calculated for 100 ms time-regions from 100 to 1500 ms after

critical word onset. Given that 180-200 ms are usually assumed to account for saccade

programming (Martin, Shao, & Boff, 1993), the mean of the first time-region (0 - 100

ms) was considered to be the baseline and used to conduct statistical comparisons

against means on all others 100 ms time-regions (for a similar method, Huettig &

Altmann, 2010). This correction to baseline allowed us to control for any bias in the

pattern of fixations on figures caused by the type of context (see Table 2). T-tests and

ANOVAs were also used for additional comparisons between conditions. We

eliminated one subject due to problems in the recording of her eye movements.

We performed 3 (context) * 2 (polarity) factorial ANOVAs and found an

interaction between context and polarity starting at 300 ms (F1(2,47)=3.212, p=.049;

F2(2,46)=5.288, p=.009). Post hoc t-tests revealed that differences between affirmative

and negative sentences were found starting at 300 ms (t1(48)=-2.070, p=.044; t2(47)=-

2.524, p=.015) for the inconsistent context. There was an increase in fixations on the

mentioned image for affirmative sentences (2%) and a decrease in fixations on the

mentioned image for negative sentences (-3%). This pattern shows that both types of

sentence started to be processed at that time, but in opposite directions, an increase on

the mentioned image for affirmative sentences and a decrease for negative sentences.


118


the baseline for the Mentioned image for affirmative and negative sentences into

contexts: neutral (NEU), inconsistent (INC) and consistent (CON). Asterisks indicate

significant differences (p<.05) with respect to baseline and the signal minus ‘-‘ indicates

a decrease of the proportion of fixation with respect to the baseline.

AF-NEU NE-NEU AF_INC NE-INC AF-CON NEG-CON

100-200 -.0035 -.0105 .0064 -.0162 -.0177 .0076

100-300 -.0074 -.0087 .0156 -.0327 -.0137 .0165

100-400 .0036 -.0030 .0337 -.0439 -.0044 .0388

100-500 .0581 -.0151 .0750* -.0536* .0056 .0621*

100-600 .1345* -.0300 .1671* -.0824* .0400 .0814*

100-700 .1681* -.0455 .2757* -.1262* .0949* .0967*

100-800 .2079* -.0866* .3457* -.1967* .1261* .0808*

100-900 .2341* -.1221* .4003* -.2755* .1342* .0665

100-1000 .2643* -.1694* .4342* -.3359* .1373* .0551

100-1100 .2687* -.2028* .4591* -.3830* .1481* .0251

100-1200 .2671* -.2109* .4684* -.4113* .1564* -.0083

100-1300 .2558* -.2246* .4725* -.4302* .1574* -.0172

100-1400 .2640* -.2424* .4762* -.4335* .1531* -.0356

100-1500 .2622* -.2696* .4725* -.4458* .1516* -.0466

There was also a main effect of polarity (F1(1,48)=5.308, p=.026;

F2(1,47)=9.051, p=.004) in addition to the interaction (F1(2,47)=8.851, p=.001;

F2(1,46)=12.802, p<.001) starting at 500 ms. This main effect of polarity shows that

affirmative and negative sentences are different across all contexts. In the neutral

context, we found differences between both types of sentences (t1(48)=-2.071, p=.044;

t2(47)=-2.132, p=.038), an increase in fixations on the mentioned image for affirmative

sentences (6%) and a decrease in fixations on the mentioned image for negative

sentences (-2%). From Table 2, there was an increase in fixation probabilities on the

mentioned image starting at 600 ms for affirmative sentences (t1(48)=4.344, p<.001;

t2(47)=3.900, p<.001) while there was a decrease on the mentioned image starting at


119

800 ms for negative sentences (t1(48)=-3.014, p=.004; t2(47)=-2.620, p=.012)

compared to the baseline. This is the typical effect of negation found in most of the

studies when negation is presented out of context: negation is harder than affirmation.

In this case, when the critical word is negated, the differences from the baseline

appeared later than when the critical word is affirmative. In the inconsistent context, the

pattern of results was similar but appeared much earlier. There was an increase in

fixation probability on the mentioned image for affirmative sentences (t1(48)=2.430,

p=.019; t2(47)=3.455, p=.001) and a decrease on the mentioned image for negative

sentences (t1(48)=-2.044, p=.046; t2(47)=-1.859, p=.069) compared to the baseline

starting at 500 ms (see Table 1). This result proves that negation is processed as easily

as affirmation when it is presented in an appropriate context, that is, for example, when

negation is used to deny a belief, as in the inconsistent context condition.

Finally, there were differences between affirmative and negative sentences at

500 ms (t1(48)=2.103, p=.041; t2(47)=1.834, p=.073) in the consistent context, an

increase in fixations on the mentioned image for negative sentences (6%) and no

change for affirmative sentences (1%). This finding would indicate that when

participants heard the affirmative sentence ‘her dad was poor’ after a context with the

same information, the processing of affirmative sentences was delayed (700 ms

compared to the baseline; t1(48)=3.518, p=.001; t2(47)=3.009, p=.004); however when

participants were focusing on the image of the rich man and heard ‘not poor’, they

needed to change their attention to the poor man in processing “not poor” (500 ms

compared to the baseline; t1(48)=2.736, p=.009; t2(47)=2.706, p=.009). Finally,

participants seems to recognize that ‘not poor’ means ‘rich’, and there was a decrease in

fixations on the mentioned image (poor) to attend the alternative (rich) again. In sum,


120

for negative sentences in the consistent context, individuals started looking at the rich

man after context, they increased their visual attention on the poor man after hearing

‘not poor’ and finally, they realized that ‘not poor’ is rich and decreased their visual

attention on poor man to attend the rich man again. All those inferences are time-

consuming.

In sum, as mentioned in the introduction the comprehension of negation

supposes a change of attention from the mentioned word toward the alternative, and

results showed that the shift of attention occurs earlier for inconsistent contexts

compared to neutral contexts and consistent context. These findings suggest that the

comprehension of negation is as fast as affirmation in the inconsistent context, that is,

when negation is used to deny a false belief.


The goal of this study was to explore how the unfolding processing of negation is

modulated by context. The results corroborated the classical effect of negation in a

neutral context with the visual world paradigm. There was an increase in fixation on the

mentioned concept for affirmative sentences starting at 600 ms but a decrease in

fixation on the mentioned concept for negative sentences starting at 800 ms. This result

shows that the processing of negation is more difficult than that of affirmation (see

Carpenter & Just, 1975; Clark & Chase, 1972; Mayo et al., 2004; Trabasso et al., 1971;

Wason & Johnson-Laird, 1972; Wason & Jones, 1963) and our paradigm was sensitive

enough to detect it. Our eye-movement data also corroborates that the effect of negation

is removed when negation is used to deny a belief. We found a difference compared to


121

the baseline starting at 500 ms for both, affirmative and negative sentences in the

inconsistent context. The advantage of using the visual world paradigm is that this

method allows us to see online, within each time window, what people do when they

process negation in those contexts. For example, when the participants were focusing on

the mentioned concept (poor) in the inconsistent context, and heard ‘he was not poor’,

they changed toward the alternative immediately. However, when the participants were

focusing on both images equally often in the neutral context, and heard one of them (he

was not poor), they changed toward the alternative with a delay compared to the

inconsistent context. In the first case, the mentioned word was already processed and in

the second case, more attention is needed to process the mentioned word.

These results are consistent with those of a recent study in which affirmative and

negative sentences (e.g., the figure is (not) red) were presented into a specific context

(binary context: e.g., the figure could be red or green) while four figures appeared on

the screen and eye-movements were monitored. The results showed that people shift

their attention to the actual situation after 900 ms (Chapter 6). In the present study,

participants looked at the actual situation starting at 800 ms in the neutral context. In

this sense the present study is a generalization of the previous results to everyday

contexts. However, together the studies show the relevant role of the availability of

situational knowledge (in a binary context) to process negation regardless of the content

of language (colors or others features).

Finally, the consistent context was quite different from the other contexts,

probably because it would seem odd. The increase of fixation on the mentioned word

for affirmative sentences started at 700 ms. This delay in comparison to other contexts

may be due to the target not being very informative, that is, it repeats information. As


122

the theory of relevance purports, language or communication must be relevant (Grice

1961; Wilson & Sperber, 2004), however in the consistent context, after listening to for

example, Veronica needed a new car for work. She wondered whether her dad could

help her financially. She supposed that her dad had little savings, individuals identified

that her dad was poor, thus when they heard, for example, Her dad was poor this

information is less relevant in the sense that participants already knew it. In summary,

the information that is repeated is less informative or relevant, and as result, processing

is delayed. Also, it is odd to hear the negative sentence Her dad was not poor after

hearing She supposed that her dad had enough savings as people are more likely to say:

her dad was rich. In this case, participants needed to change their attention from the

image of the rich man (after hearing the context) toward the image of the poor man

(after hearing negation) to process the mentioned word around 500 ms. And then, they

inferred that not poor is rich, so they needed to change their attention from the poor man

toward the rich man again at a later stage. These two inferences take extra time compare

to the previous contexts (see Johnson-Laird & Tridgell, 1972). The advantage of using

the visual world paradigm is that processing is registered online and it is possible to

observe each step of processing in each time window.

In conclusion, although, in general, negation is more difficult to understand than

affirmation, a context that presents the negated argument first makes negation as easy to

process as affirmation (Givon, 1978; Khemlani et al., 2012). However, in a context that

presents what is the case (as in the consistent condition), where affirmation would

normally be used, negation is difficult to process, as extra processing is required to

work out what is the case.

General Conclusion

123

9. General Conclusion

Throughout this dissertation, we have studied how individuals understand negation and

the resulting mental representations. Also, we have shown that its understanding may

improve when either the negated argument is symbolic (or non-visual) or when it is

presented in a denial context. These results corroborate the three main predictions of the

present dissertation.

We started with one of the most consistent results in literature: negation is more

difficult (larger latencies to response and higher error rates) to understand than

affirmation. Among others explanations, this result has been accounted for on the basis

of a requirement of two representational steps to understand negation (e.g., the figure is

not red), the negated situation: a red figure; and the actual situation: a green figure,

while in affirmation (e.g., the figure is red), the actual situation is directly available: a

red figure (Kaup, Lüdtke & Zwaan, 2006). The first goal of the present thesis was to

study whether this two-step processing is necessary to understand negation, or just one

possibility. Also, this is an important issue in cognitive science because processing is

related to representation. It is assumed that if people represent the actual situation (e.g.,

a green figure) to understand negation, the resulting representation is iconic because

negation is not represented explicitly, whereas if they represent just the negated

situation, this representation should be symbolic, or at least not purely iconic, because a

symbolic marker is needed to represent negation without swapping to the actual

situation. In other words, it can only be done by keeping ‘not red’ in mind. Therefore,

this topic is also important to be able to differentiate between theories of representation.

General Conclusion

124

1. Individuals are able to represent symbolic information. Results described

in the chapter 6 showed that people could well understand negation by either

representing the actual situation or by building up a symbolic representation of the

negated situation. Whether one or the other kind of representation takes place in the

mind seems to depend on the availability of the actual situation. Experiment 1 showed

that when the actual situation is available, such as in a binary context (e.g., the figure

could be red or green), participants understood negation (e.g., the figure was not red)

by changing their visual attention from the negated situation (e.g., a red figure) to the

actual situation (e.g., a green figure). This shift is time-consuming to envisage (around

900 ms) and proves that, when the actual situation is available, people tend to cancel

negation by a representation of the alternative affirmation. As Johnson-Laird (2001)

pointed out, negation can be stored as ‘mental footnotes’, but people soon lose track of

these footnotes because they are hard to remember. The alternative affirmation, though

non-negated in form, helps to further recall of the meaning of the negated sentence,

since it is easy to store and corresponds to the actual situation being described in the

sentence. Thus, negation processing instills the actual situation (if available) while

taking out the situation that is within its scope. Other studies have also shown that

negated concepts are less accessible than affirmative concepts, and hence somehow

displaced from the mind by negation (Fillenbaum 1966; Lea & Mulligan, 2002;

MacDonald & Just, 1989).

However, there are cases, such as the multary context, in which the actual

situation is not available and therefore many alternatives are possible to describe what

the actual situation is. Results of Experiment 1 also showed that participants focused on

the figure corresponding to the negated situation in the multary context. This finding is

General Conclusion

125

consistent with the possibility that negation is represented symbolically (Clark & Chase,

1972; Giora, 2006; Khemlani, Orenes, & Johnson-Laird, 2012; Mayo, Schul, &

Burnstein, 2004; Schul, 2011). This would result as consequence of the limitations of

working memory: multiple models can overload its processing capacity and lead to

errors. Johnson-Laird (2001) pointed out that the fewer the number of models needed

for an inference, the easier the inference should be by the effect of limit memory. In

short, it is likely that individuals change one negated model with one affirmative model

(alternative) because negation is hard to remember. However, people would prefer to

maintain negation rather than two or more possible affirmative models.

This latter finding was corroborated in Experiments 2 and 3, in which negative

sentences were presented without any context using two different tasks: recognition and

verification. It is important to consider the stable pattern observed in the understanding

of negation; individuals increased their attention on the negated situation from 400 ms

onwards in all experiments. This timing presents an interesting correspondence with the

timing for brain semantic processing according to event-related potentials (ERP)

research. The N400 component, which unfolds between 200-500 ms, has been

repeatedly associated with the integration of word meaning into sentence context (Kutas

& Federmeier, 2011), and therefore could be taken as an indicator of comprehension.

Although there is not much evidence in the case of negation linking its comprehension

to N400 response (the only exception being Niewland & Kuperberg, 2008), future

research should examine this possible relation using EEG and Eye-Tracking co-

registration.

Experiments 2 and 3 revealed an interesting similarity in the temporal course

fixations for the verification (e.g., could the figure be red?) and the recognition task

General Conclusion

126

(e.g., were the figures circles?). There is a debate in cognitive science as to whether

verification is an automatic comprehension process or not. For instance, Fischler and

colleagues (1983) found that both affirmative sentences (e.g., a robin is a bird/tree) and

negative sentences (e.g., a robin is not a bird/tree) elicited identical ERP effects in

sentence category verification tasks, with no systematic differences observed between

true and false sentences. Specifically, they observed that in both affirmative and

negative sentences, object nouns elicited a larger N400 component when they were

categorically unrelated to the subject noun (robin-tree) than when they were related

(robin-bird). This seems to suggest that the validation of the truth of a sentence is not a

case of automatic processing. However, Richter, Schroeder, and Wöhrmann (2009)

showed that reading true sentences (e.g., perfume contains scents) as compared to false

sentences (e.g., soft soap is edible) activated more correct responses in an orthographic

task, even though a truth validation was not required. Wiswede et al. (2012) presented

affirmative and negative sentences (e.g., Saturn is a planet; Saturn is not a planet;

Saturn is a continent; Saturn is not a continent) which participants were instructed to

read. After that, either verification or identification tasks were conducted. The results

showed the classical interaction between polarity and truth value for the verification

task. Participants identified the probe words ‘true’ and ‘false’ faster when they matched

the truth content (e.g., Saturn is (not) a planet) than when they did not, and it was also

slower for negative sentences than for affirmative sentences. No difference was

observed between conditions in the identification task, where participants had to

indicate if the sentence were identical to a probe sentence or not. This would appear to

indicate that the validation of the truth value of the sentences was not an automatic

process. Thus, these findings support theories postulating that the processing of truth

General Conclusion

127

value is goal-dependent (e.g., Dodd & Bradshaw, 1980; Green & Brock, 2000; Schul,

Mayo, & Burnstein, 2004). Apparently, evaluating the truth value of a proposition does

not automatically occur whenever a sentence is read and understood, but must be

regarded as a conditionally automatic process, the occurrence of which depends on the

requirements of the task at hand and the resulting mindset.

Carpenter and collaborators (1999) presented a sentence-picture verification task

using functional magnetic resonance imaging, and the results showed higher activation

in the left posterior temporal gyrus related to language comprehension and higher

activation in the left and right parietal regions related to the visuospatial processing. The

higher activation for negative rather than affirmative assertions was related to the

increased processing difficulty. At the same time, Tettamanti and collaborators (2008)

found that negation deactivated cortical areas and the left pallidum, which could be

interpreted as a reduction in access to mental representations of the concept being

negated. These two studies would seem to be contradictory, but the presentation format

of the sentences and the tasks could explain these differences. When people listened to

the sentences in Tettamanti’s study, access to the negated word was reduced, while

when people were asked to decide whether an image corresponded or not to the

previous negated sentence in the verification task in Carpenter’s study, the comparison

of the sentence and the image must have been more difficult (higher activation) for

negation than for affirmation, because there was no image matching the negation

(Khemlani et al., 2012). For example, when participants read a negative sentence: ‘It is

not true that the star is above the plus’, they needed to infer that ‘the star is below the

plus’ or ‘the plus is above the star’; however when they read an affirmative sentence ‘It

is true that the star is above the plus’, there was a correspondence between the sentence

General Conclusion

128

and their representation, that is, ‘the star is above the plus’. Therefore, both studies are

relevant because they allow us to dissociate between comprehension, related to the

reduction of activation for negation as compared to affirmation, and verification, related

to a higher activation due to the comparison between the sentence and the picture. This

dissociation allows us to be aware about the role of the task in the comprehension of

negation.

In general, our findings in Experiments 1, 2 and 3 are opposed to the mandatory

view of two-step theory, which predicts that individuals will always understand

negation by representing the actual situation (e.g., representing the door is not open by a

closed door). This form of processing negation fits well with the embodiment theory,

one of the dominant frameworks in cognitive science that holds that all representations,

including those relating to abstract concepts, must be iconic to the world (Barsalou,

1999; 2005; 2012; Glenberg et al., 1987; Lakoff & Johnson, 1980; Zwaan &

Radvansky, 1998). Our results were, in contrast, consistent with the mental model

theory, which, while holding that most representations are iconic, also allows for the use

of combinations with symbolic representations (Johnson-Laird, 1983; 2006).

In summary, individuals are able to understand negation with just one step, and

consequently, negation could be symbolically represented. At this point, we can reject

the hypothesis that the difficulty of negation comes from the two-step processing

because it is not always necessary. This opens a new possible explanation: negation is

more difficult because it has a symbolic representation. A number of studies have

shown the advantages of iconic representation. What we did in the next study was to

find one exception to the supposed iconic advantage. We predicted that an abstract

General Conclusion

129

(non-iconic) argument would make negation easier to understand than an iconic

argument.

2. Visual concepts could impede negation. Chapter 7 showed that the negation

of arguments involving visual words (related to iconic representation; e.g., the boy was

brave and he was not asleep) was slower than negation involving non-visual words

(related to verbal or symbolic representation; e.g., the boy was awake and he was not

cowardly). This finding was corroborated in two experiments. In Experiment 1, we

presented the previous sentences followed by a target sentence with the same meaning

as the previous one, but with a replacement of the previously negated word with its

contrary (e.g., the boy was brave and he was awake). The target sentence was similar

for both conditions, but participants took longer to read the target sentence after the

negation of the visual argument than the non-visual argument, even thought visual

concepts were easier than non-visual concepts in a lexical decision task previously

carried out. In Experiment 2, we found the same results. In this case, we presented the

same sentence as the previous one but without negation (e.g., the boy was brave and he

was asleep). Both experiments showed that iconic representation could impede some

symbolic operations such as negation. This finding is very relevant because other

authors have also found that visual relations slowed down the process of reasoning

(relational inference and conditional reasoning) compared to control relations,

visuospatial and spatial relations (Knauff , 2009; 2013; Knauff & Johnson-Laird, 2002).

Taken together, we could conclude that although iconic representation has enormous

advantages in cognition, its semantic richness could be unnecessary in certain cognitive

processing such as negation. For example, it could be easier to negate a symbolic

representation of a cowardly child than an iconic representation of a sleeping child. That

General Conclusion

130

is, the negation of an image could contain details that are irrelevant to the processing,

and consequently it could be slower. It leads to a more general and remarkable

conclusion: negation and certain types of reasoning are better applied to the concepts

related to abstraction than to the images related to figuration and concreteness. In short,

symbolic representation is essential in cognition because it reduces the processing load

on working memory and allows more complex operations to proceed without the

interference of unnecessary representational elements.

Before finishing this part, I would like to relate our results with some theories of

representation. The context availability theory holds that concrete concepts are more

difficult than abstract concepts by effect of context (Kieras, 1978; Schwanenflugel &

Shoben, 1983). According to this theory, concrete concepts can activate more semantic

information in isolation than abstract concepts. This increase of activation would

provoke the typical concreteness effect, but it would vanish when both types of

concepts are presented in equally supporting sentence contexts. In Experiment 1

(chapter 7), we presented a supportive context (e.g., the boy was brave and he was not

asleep) and the second sentence (the target) was highly predictable (e.g., the boy was

brave and he was awake); however the results were not similar for visual and non-

visual conditions, as the context availability theory would predict.

A similar case occurs with the framework that defends qualitative differences in

the organization of concrete and abstract concepts in the mental lexicon, that is,

concrete concepts would be primarily organized following a semantic similarity

principle, whereas abstract concepts would be mainly organized by their association

with other concepts (e.g., Crutch, 2006; Crutch & Warrington, 2005; Crutch, Ridha &

Warrington, 2006; Duñabeitia et al, 2009; Warrington & Crutch, 2007). Experiment 1

General Conclusion

131

(chapter 7) shows that the negation of non-visual concepts was faster than visual

concepts. This could prove this framework because non-visual words would activate

their associates, as happening in the second sentence of Experiment 1 (e.g., not

cowardly-brave). However, we found the same result in Experiment 2 when the same

word (e.g., not cowardly- cowardly) and not its associate was presented. Thus, the

associate is not the factor that explains the differences between both types of words.

Recently, Kousta, Vigliocco and Del campo (2011) have found an advantage for

abstract words rather than concrete words in a lexical decision when they match in

imageability and the two sorts of words differ only on emotionality (see also, Barber et

al., 2013). We found the opposite results in a lexical decision experiment where

imageability was manipulated. Both results could indicate that imagery is a necessary

and sufficient factor for the concreteness effect because when this factor is present, we

found the effect as literature has showed in several studies; however, when this variable

is absent, the effect disappeared. To control the emotionality of our eighty words in both

experiments in chapter 7, we asked 55 participants to rate the two dimensions of

emotionality: the valence, whose range extends from unpleasant to pleasant (1-9), and

the activation, extending from calm to excitation (1-9), by the Self-Assessment Manikin

(SAM) using the program E-PRIME 2.0. The procedure was the same as that of

Redondo and collaborators (2005). The results showed higher valence for visual words

(5.43; sd=.47) than non-visual words (5.15; sd=.41; F(1,54)=21.713, p<.001). An

average around 5 would indicate that the words were neutral. However, the activation

was higher for non-visual (4.74; sd=1.55) than visual words (3.73; sd=1.54;

F(1,54)=92.692, p<.001). Therefore, our results do not seem to be due to the grade of

emotionality. One relevant question for future research would be a meta-analysis that

General Conclusion

132

could point out the effect of the percentage that is explained in each case by the grade of

visualization, the emotionality, the frequency, the type of task and other variables on the

processing of words (see for example, Zdrazilova & Pexman, 2013).

3. Inconsistency contexts make negation more plausible. Results described in

chapter 7 allow rejection of the possibility that the difficulty of negation is related to its

representation. Our hypothesis is semantic (Miller, 1962). That is, negation has a more

complex semantic meaning than the corresponding affirmation. Negation (e.g., non-red)

adds semantic richness to the argument that it takes (e.g., red). If this hypothesis is true,

then when we use an affirmation (e.g., her dad was poor) in a neutral context (e.g., her

dad lived on the other side of town), it should be easier than the negation (e.g., her dad

was not poor) which adds semantic information as we said above. However, if

affirmation and negation are used to deny an argument, then both of them would add

semantic information and no differences between then are expected. That is, we hold

that negation is more difficult than affirmation because it denies an argument and adds

semantic information, therefore if affirmation is used similarly, then both of them

should be equally easy. In other words, if we presented affirmative sentences to deny a

false belief: She supposed that her dad had enough savings and thereafter it is said: her

dad was poor, it should be equally easy as the negation (e.g., her dad was not poor

followed by She supposed that her dad had little savings). Results of chapter 8

corroborated our hypothesis using the visual world paradigm.

It is interesting to find that affirmative and negative sentences were easier when

they were used to deny a false belief than in a neutral context because in the first case

individuals needed to change a belief and literature suggests that once beliefs are held,

they are difficult to change. This means that people tend to maintain their beliefs even

General Conclusion

133

when faced with evidence that is contrary or inconsistent (Khemlani & Johnson-Laird,

2012; Orenes et al., 2012). From this premise, one could predict that when people listen

to a context that is inconsistent with the target, this latter must be understood slowly (see

Ferguson, Sanford, & Leuthold, 2008). However, our results show that both affirmative

and negative sentences are processed faster in the inconsistent context (when they are

used to deny or change a belief) than in a neutral context maybe due to a priming effect.

In our experiment, we presented a context that predicted if her dad was rich or poor. For

example, ‘She supposed that her dad had enough savings’ and then it was rejected: ‘Her

dad was poor/her dad was not rich’. This inconsistent context may make one think of

rich or poor man rather than the neutral context which does not activate any of these

concepts: Her dad lived on the other side of town. As Khemlani and collaborators

(2012) point out, individuals should find easier to understand a negation if they have

already constructed the models of the corresponding affirmative assertion.

In summary, both of the sentences, affirmative and negative, could be processed

similarly when they are use to deny a false belief as we have shown in our previous

study. This could indicate the importance of falsity on negation. I believe that they must

be quite similar in language production, but there are not many studies about that,

because negation is used to falsify. That is, we can say ‘no’ or ‘it is false’. However,

many comprehension tasks, such as verification, have found that false sentences are

easier than negative sentences. For example, if people read ‘the figure is red’ and then a

green figure appeared. They compared both representations, a red figure and a green

figure, and easily found a mismatch. However, negation is not easy to match with an

image; therefore this processing could be more complex. For example, if people read

‘the figure is not red’ and then a green figure appeared. They needed to infer that ‘the

General Conclusion

134

figure is not red’ is a green figure, and this step, as we have studied along the

dissertation, takes time, therefore it could need more time than the first comparison.

Our general conclusion from the present thesis would be that the syntactic

operator of negation is difficult because it adds semantic information to the argument

that it takes, specifically reverses the truth value of the argument, and this function

could only be represented symbolically. Individuals are able to understand negation

symbolically and this type of representation also improves its computation and

comprehension. Furthermore, when negation is used to deny a belief, it could be as easy

as affirmation. To sum up, negation has an essential linguistic function, to falsify an

argument or to correct a misconception, and this should be fundamental to the cognitive

system, since it is presented in natural and artificial languages and from an early age.

References

135

References

Allopenna, P., Magnuson, J.S. & Tanenhaus, M.K. (1998) Tracking the time course of

spoken word recognition using eye-movements: evidence for continuous mapping

models. Journal of Memory and Language, 38(4), 419-439.

Altmann, G.T.M. (2011). The mediation of eye movements by spoken language. In S.P.

Liversedge, I.D. Gilchrist, & S. Everling (Eds.), The Oxford Handbook of Eye

Movements (pp. 979-1003). Oxford: OUP.

Altmann, G.T.M., & Kamide, Y. (1999). Incremental interpretation at verbs: restricting

the domain of subsequent reference. Cognition 73, 247-264.

Altmann, G.T.M., & Kamide, Y. (2004). Now you see it, now you don't: Mediating the

mapping between language and visual world. In J.Henderson & F. Ferreira

(Eds.), The interface of language, vision, and action: Eye movements and the

visual world. New York: Psychology Press.

Anderson, S., Huette, S., Matlock, T., & Spivey, M. (2010). On the temporal dynamics

of negated perceptual simulations. In F. Parrill, V. Tobin, & M. Turner (Eds.),

Meaning Form and Body (pp. 1-20). Stanford University, California: CSLI

Publications.

Aristotle. (1984). The complete works of Aristotle, Vols. 1 and 2. In J. Barnes (Eds.),

Princeton, NJ: Princeton University Press.

Barber, H.A., Otten, L.J., Kousta, S.T., & Vigliocco, G. (2013). Concreteness in word

processing: ERP and behavioural effects in a lexical decision task. Brain &

Language. 125, 47-53.

References

136

Barclay, J.R. (1973). The role of comprehension in remembering sentences. Cognitive

Psychology, 4, 229-254.

Barr D.J. (2008) Analyzing ‘visual world’ eyetracking data using multilevel logistic

regression. Journal of Memory and Language, Special Issue: Emerging Data

Analysis, 59, 457-474.

Barsalou, L.W. (1999). Perceptual symbol systems. Behavioral and Brain Sciences, 22,

577-660.

Barsalou, L.W. (2005). Continuity of the conceptual system across species. Trends in

Cognitive Science, 9, 309-311.

Barsalou, L.W. (2008). Grounded Cognition. Annual Review of Psychology, 59, 617-

645.

Barsalou, L.W. (2012). The Human conceptual system. In M.J. Spivey, K. Mcrae, &

M.F. Joanisse (Eds.), The Cambridge Handbook of Psycholinguistics, Cambridge

(pp. 239-258). University Press.

Beltrán, D., Orenes, I., & Santamaría, C. (2008). Context effects on the spontaneous

production of negation. Intercultural Pragmatics, 5-4.

Bransford, J.D., Barclay, J.R., & Franks, J.J. (1972). Sentence memory: a constructive

versus interpretive approach. Cognitive Psychology, 3, 193-209.

Bruner, J.S., Goodnow, J.J., & Austin, G.A. (1956). A Study of Thinking. New York:

Wiley.

Byrne, R.M.J. (2005). The rational imagination: How people create alternatives to

reality. CA: MIT Press.

Carpenter, P.A., & Just, M.A. (1975). Sentence comprehension: A psycholinguistic

processing model of verification. Psychological Review, 82, 45-73.

References

137

Carpenter, P.A., Just, M.A., Keller, T.A., Eddy, W.F., & Thulborn, K.R. (1999). Time

course of fMRI-Activation in language and spatial networks during sentence

comprehension. NeuroImage, 10, 216-224.

Clark, H.H. (1969). Linguistic processes in deductive reasoning. Psychological Review,

76, 387-404.

Clark, H.H. (1974). Semantics and comprehension. In T.A. Sebeok (Eds.), Current

trends in linguistics, Vol. 12: Linguistics and adjacent arts (pp. 1291-1428). The

Hague: Mouton.

Clark, H. H., & Chase, W.G. (1972). On the process of comparing sentences against

pictures. Cognitive Psychology, 3, 472-517.

Cooper, R.M. (1974). The control of eye fixation by the meaning of spoken language: a

new methodology for the real-time investigation of speech perception, memory,

and language processing. Cognitive Psychology, 6, 84-107.

Craik, F.I.M. & Tulving, E. (1975). Depth of processing and the retention of words in

episodic memory. Journal of Experimental Psychology: General, 104, 268-94.

Crutch, S.J. & Warrington, E.K. (2005). Abstract and concrete concepts have

structurally different representational frameworks. Brain, 128, 615-627.

Crutch, S.J. (2006). Qualitatively different semantic representations for abstract and

concrete words: further evidence from the semantic reading errors of deep

dyslexic patients. Neurocase, 12, 91-97.

Crutch, S.J., Ridha, B.H., & Warrington, E.K. (2006). The different frameworks

underlying abstract and concrete knowledge: evidence from a bilingual patient

with a semantic refractory access dysphasia. Neurocase, 12, 151-163.

References

138

Dale, R., & Duran, N.D. (2011). The cognitive dynamics of negated sentence

verification. Cognitive Science, 35, 983-996.

Davis, C.J., & Perea, M. (2005). BuscaPalabras: A program for deriving orthographic

and phonological neighborhood statistics and other psycholinguistic indices in

Spanish. Behavior Research Methods, 37, 665-671.

Denis, M. (1989). Image et cognition. Paris: Presses Universitaires de France.

De Soto, C.B., London, M., & Handel, S. (1965). Social reasoning and spatial paralogic.

Journal of personality and social psychology, 2, 513-521.

Dodd, D.H., & Bradshaw, J.M. (1980). Leading questions and memory-pragmatic

constraints. Journal of Verbal Learning and Verbal Behavior, 19(6), 695-704.

Donders, F.C. (1969). On the speed of mental processes. In W.G. Koster (Eds.),

Attention and Performance II, vol 30 (pp. 412-431). Amsterdam: North-Holland.

Duñabeitia, J.A., Avilés, A., Afonso, O., Scheepers, C. & Carreiras, M. (2009).

Qualitative differences in the representation of abstract versus concrete words:

Evidence from the visual-world paradigm. Cognition, 110, 284-292.

Edwards, S., & Pratt, S. (2009). Rationality in collective decision-making by ant

colonies. Proceedings of the Royal Society B: Biological Sciences.

Eifermann, R.R. (1961). Negation: a linguistic variable. Acta Psychologica, 18, 258-

273.

Evans, J.St.B.T. (1972). Interpretation and matching bias in a reasoning task. British

Journal of Psychology, 24, 193-199.

Ferguson, H.J., Sanford, A.J., & Leuthold, H. (2008). Eye-movements and ERPs reveal

the time course of processing negation and remitting counterfactual worlds. Brain

Research, 1236, 113-125.

References

139

Ferguson, H.J., Scheepers, C., & Sanford A.J. (2010). Expectations in counterfactual

and theory of mind reasoning. Language and Cognitive Processes, 25(3), 297-

346.

Fernández, A., Díez, E., Alonso, M.A., & Beato, M.S. (2004). Free-association norms

for the Spanish names of the Snodgrass and Valderwart pictures. Behavior

Research Methods, Instruments, & Computers, 36, 577-583.

Fillenbaum, S. (1966). Memory for gist: Some relevant variables. Language and

Speech, 9, 217-227.

Fischler, I., Bloom, P., Childers, D., Roucos, S., & Perry, N. (1983). Brain potentials

related to stages of sentence verification. Psychophysiology, 20, 400-409.

Freud, S. (1925). Negation. In J. Strachey (Eds.), Complete psychological works of

Sigmund Freud, Vol. 19: The ego and the id and other works (pp. 181-185).

London: Hogarth.

Giora, R. (2006). Anything negatives can do affirmatives can do just as well, except for

some metaphors. Journal of Pragmatics 38, 981-1014.

Giora, R., Fein, O., Aschkenazi, K., & Alkabets-Zlozover, I. (2007). Negation in

Context: A functional approach to suppression. Discourse processes, 43(2), 153-

172.

Giora, R., Heruti, V., Metuki, N., & Fein, O. (2009). “When we say no we mean no”

Interpreting negation in vision and language. Journal of Pragmatics, 41, 2222-

2239.

Givón, T. (1978). Negation in language: Pragmatics, function, ontology. Syntax and

Semantics, 9, 69-105.

References

140

Glenberg, A.M., Meyer, M., & Lindem, K. (1987). Mental models contribute to

foregrounding during text comprehension. Journal of Memory and Language, 26,

69-83.

Glenberg, A.M., Robertson, D.A., Jansen, J.L., & Johnson-Glenberg, M.C. (1999). Not

propositions. Journal of Cognitive Systems Research, 1, 19-33.

Green, M.C., & Brock, T.C. (2000). The role of transportation in the persuasiveness of

public narratives. Journal of Personality and Social Psychology, 79(5), 701-21.

Grice, H.P. (1961). The causal theory of perception. Proceedings of the Aristotelian

Society, Supp. Vol. XXXV, 121-153.

Hasson, U., & Glucksberg, S. (2006). Does understanding negation entail affirmation?

An examination of negated metaphors. Journal of Pragmatics, 38, 1015-1032.

Hayhoe M., & Ballard, D. (2005) Eye movements in natural behavior. TRENDS in

Cognitive Sciences, 9(4), 188-193.

Heller, D., Grodner, D., & Tanenhaus, M.K. (2008). The role of perspective in

identifying domains of references. Cognition, 108, 811-836.

Horn, L.R. (1989). A natural history of negation. Chicago: Chicago University Press.

Huettig, F., & Altmann, G.T. (2010). ‘Looking at anything that is green when hearing

“frog”: How object surface colour and stored object colour knowledge influence

language-mediated overt attention. The Quarterly journal of Experimental

psychology, I, 1-24.

Huettig, F., Rommers, J., & Meyer, A.S. (2011). Using the visual world paradigm to

study language processing: A review and critical evaluation. Acta

Psychologica, 137, 151-171.

References

141

Jaeger, T.F. (2008). Categorical Data Analysis: away from ANOVAs (transformation or

not) and towards Logit Mixed Models. Journal of Memory and Language, 59,

434-446.

Johnson-Laird, P.N. (1983). Mental models: Towards a cognitive science of language,

inference, and consciousness. Cambridge, MA: Harvard University Press.

Johnson-Laird, P.N. (2001). Mental models and deduction. TRENDS in Cognitive

Sciences, 5(10), 434-442.

Johnson-Laird, P.N. (2006). How We Reason. Oxford: Oxford University Press.

Johnson-Laird, P.N., & Bethell-Fox, C. (1978). Memory for questions and amount of

processing. Memory and Cognition, 6, 496-501.

Johnson-Laird, P.N., & Tridgell, J. (1972). When negation is easier than affirmation.

Quarterly Journal of Experimental Psychology, 24, 87-91.

Jones, S. (1966). The effect of a negative qualifier in an instruction. Journal of Verbal

Learning and Verbal Behavior, 5, 497-501.

Jones, S. (1968). Instructions, self-instructions and performance. Quarterly Journal of

Experimental Psychology, 20, 74-781.

Just, M.A., & Carpenter, P.A. (1976). Eye fixations and cognitive processes. Cognitive

psychology, 8, 441-480.

Kaup, B., (2001). Negation and its impact on the accessibility of text information.

Memory & Cognition, 20, 960-967.

Kaup, B., Lüdtke, J., & Zwaan, R.A. (2006). Processing negated sentences with

contradictory predicates: Is a door that is not open mentally closed?. Journal of

Pragmatics, 38, 1033-1050.

References

142

Kaup, B., Zwaan, R.A., & Lüdtke, J. (2007). The experiential view of language

comprehension: How is negated text information represented?. In F. Schmalhofer,

& C.A. Perfetti (Eds.), Higher level language processes in the brain: Inference

and comprehension processes (pp. 255-288). Mahwah, NJ: Erlbaum.

Khemlani, S., & Johnson-Laird, P.N. (2012). Hidden conflicts: Explanations make

inconsistencies harder to detect. Acta Psychologica, 139, 486-491.

Khemlani, S., Orenes, I., & Johnson-Laird, P.N. (2012). Negation: A Theory of its

Meaning, Representation, and Use. Journal of Cognitive Psychology, 24, 541-559.

Kieras, D. (1978). Beyond pictures and words: Alternative information processing

models for imagery effects in verbal memory. Psychological Bulletin, 85, 532-

554.

Klima, E.S. (1964). Negation in English. In J.A. Fodor & J.J. Katz (Eds.), The structure

of Language (pp. 246-323). Englewood Cliffs, NJ: Prentice Hall.

Knauff, M. (2009). A neuro-cognitive theory of deductive relational reasoning with

mental models and visual images. Spatial Cognition & Computation, 9(2), 109-

137.

Knauff, M. (2013). Space to reason: A spatial theory of human thought. Cambridge,

MA: MIT Press.

Knauff, M., Fangmeier, T., Ruff, C.C., & Johnson-Laird, P.N. (2003). Reasoning,

models, and images: behavioral measures and cortical activity. Journal of

Cognitive Neuroscience, 15, 559-573.

Knauff, M., & Johnson-Laird, P.N. (2002). Imagery can impede inference. Memory &

Cognition, 30, 363-371.

References

143

Knauff, M., & May, E. (2006). Mental imagery, reasoning, and blindness. Quarterly

Journal of Experimental Psychology, 59, 161-177.

Kousta, S.T., Vigliocco, G., Vinson, D.P., Andrews, M., & Del Campo, E. (2011). The

representation of abstract words: Why emotion matters. Journal of Experimental

Psychology: General, 140(1), 14–34.

Kutas, M. & Federmeier, K.D. (2011). Thirty years and counting: Finding meaning in

the N400 component of the event-related brain potentials. Annual Review of


Lakoff, G., & Johnson, M. (1980). Metaphors we live by. Chicago: University of

Chicago Press.

Lawrence, B.M., Myerson, J., & Abrams, R.A. (2004). Interference with spatial

working memory: An eye movement is more than a shift of attention.

Psychonomic Bulletin & Review, 11(3), 488-494.

Lea, R.B., & Mulligan, E.J. (2002). The Effect of Negation on Deductive Inferences.

Journal of Experimental Psychology: Learning, Memory, and Cognition, 28(2),

303-317.

Liversedge, S.P., & Findlay, J.M. (2000). Eye movements reflect cognitive

processes. Trends in Cognitive Science 4(1), 6-14.

Lüdtke, J., Friedrich, C.K., De Filippis, M., & Kaup, B. (2008). ERP Correlates of

Negation in a Sentence-Picture-Verification Paradigm. Journal of Cognitive

Neuroscience, 20(8), 1355-70.

Lüdtke, J., & Kaup, B. (2006). Context effects when reading negative and affirmative

sentences (poster). 28th Annual Conference of the Cognitive Science Society.

References

144

MacDonald, M.C., & Just, M.A. (1989). Changes in activation levels with negation.

Journal of Experimental Psychology: Learning, Memory and Cognition, 15(4),

633-642.

Martin, E., Shao, K.C., & Boff, K.R. (1993). Saccadic overhead –Information-

processing time with and without saccades. Perception & Psychophysics, 53, 372-

380.

Mayo, R., Schul, Y., & Burnstein, E. (2004). “I am guilty” vs. “I am innocent”:

Successful negation may depend on the schema used for its encoding. Journal of

Experimental Social Psychology, 40, 443-449.

Miller, G.A. (1962). Some psychological studies of grammar. American Psychologist,

17, 748-762.

Mirman, D., Dixon, J.A., & Magnuson, J.S. (2008). Statistical and computational

models of the visual world paradigm: Growth curves and individual differences.

Journal of memory and language, 59, 475-494.

Morris, B., & Hasson, U. (2010). Multiple sources of competence underlying the

comprehension of inconsistencies: A developmental investigation. JEP: Learning,

Memory, and Cognition, 36, 277-287.

Moxey, L.M., & Sanford, A.J. (1987). Quantifiers and focus. Journal of Semantics, 5,

189-206.

Nieuwland, M.S., & Kuperberg, G.R. (2008). When the truth is not too hard to handle:

An Event-Related Potential study on the Pragmatics of Negation. Psychological

Science, 19(12), 1213-1218.

References

145

Nieuwland, M.S., & Martin, A.E. (2011). If the real world were irrelevant, so to speak:

The role of propositional truth-value in counterfactual sentence comprehension.

Cognition, 122(1), 102-109.

Orenes, I., Navarrete, G., Beltrán, D., & Santamaría, C. (2012). Schizotypal people stick

their first choices. Psychiatry Research, 200, 620-628.

Paivio, A. (1983). The empirical case for dual coding. In J. C. Yuille (Eds.), Imagery,

memory and cognition: Essays in honor of Allan Paivio (pp.307-332). Hillsdale,

NJ: Erlbaum.

Paivio, A. (1986). Mental representations: a dual coding approach. Oxford, England:

Oxford University Press.

Paivio, A. (1991).Dual coding theory: Retrospect and current status. Canadian Journal

of Psychology, 45(3), 255-287.

Paivio, A. (2007). Mind and its evolution: A dual coding theoretical approach.

Mahwah, NJ: Erlbaum.

Paivio, A. (2013). Dual coding theory, word abstractness, and emotion: A critical

review of Kousta et al. (2011). Journal of Experimental Psychology: General,

142, 282-287.

Peirce, C.S. (1931-1958). Collected papers of Charles Sanders Peirce. In C.

Hartshorne, P. Weiss, & A. Burks (Eds.), 8 Vols. Cambridge, MA: Harvard

University Press.

Posner, M.I. (1980). Orienting of attention. The quarterly journal of experimental

psychology, 32(1), 3-25.

Rayner, K. (1978). Eye movements in reading and information processing.

Psychological Bulletin, 85, 618-660.

References

146

Rayner, K. (1998) Eye Movements in Reading and Information Processing: 20 Years of

Research. Psychological Bulletin, 24 (3), 372-422.

Redondo, J., Fraga, I., Montserrat, C., & Perea, M. (2005). Estudio normativo del valor

afectivo de 478 palabras españolas. Psicológica, 26, 317-326.

Richter, T., Schroeder, S., & Wöhrmann, B. (2009). You don´t have to believe

everything you read: Background knowledge permits fast and efficient validation

of information. Journal of Personality and Social Psychology, 96(3), 538-58.

Rorty, R. (1982). Method, Social Science, Social Hope. In R. Rorty (Eds.),

Consequence of Pragmatism (Essays: 1972-1980; pp. 191-210), Minneapolis:

University of Minnesota Press.

Russell, B.A.W. (1948). Human Knowledge: Its Scope and Limits. London: George

Allen & Unwin.

Salverda, A.P., & Altmann, G.T.M. (2011). Attentional capture of objects referred to by

spoken language. Journal of Experimental Psychology: Human Perception and

Performance. 37, 1122-1133.

Salverda, A.P., Brown, M., & Tanenhaus, M.K. (2011). A goal-based perspective on

eye movements in visual world studies. Acta Psychologica, 137(2), 172-180.

Scheepers, C. (2003). Syntactic priming of relative clause attachments: Persistence of

structural configuration in sentence production. Cognition, 89, 179-205.

Scheepers, C., Keller, F., & Lapata, M. (2008) Evidence for serial coercion: A time

course analysis using the visual-world paradigm. Cognitive Psychology, 56, 1-29.

Schul, Y. (2011). Alive or not dead: Implications for framing from research on

negations. In G. Keren (Eds.), Perspective on Framing (pp. 157-176). NY:

Psychology Press.

References

147

Schul, Y., Mayo, R., & Burnstein, E. (2004). Encoding under trust and distrust: The

spontaneous activation of incongruent cognitions. Journal of Personality and

Social Psychology, 86(5), 668-79.

Schwanenflugel, P.J, & Shoben, E.J. (1983). Differential context effects in the

comprehension of abstract and concrete verbal materials. Journal of Experimental

Psychology: Learning, Memory, & Cognition, 9, 82-102.

Soto, D., & Humphreys, G.W. (2007). Automatic guidance of visual attention from

verbal working memory. Journal of Experimental Psychology: Human Perception

and Performance, 33(3), 730-757.

Stalnaker, R. (1998). On the representation of context. Journal of Logic, Language, and

Information, 7, 3-19.

Sternberg, R.J. (1980). Representation and process in linear syllogistic reasoning.

Journal of Experimental Psychology: General, 109, 119-159.

Strawson, P. (1952). Introduction to logical Theory. London: Methuen and CO.

Tanenhaus, M. K., Spivey-Knowlton, M. J., Eberhard, K. M., & Sedivy, J. C. (1995).

Integration of visual and linguistic information in spoken language

comprehension. Science, 268(5217), 1632-1634.

Tettamanti, M., Manenti, R., Della Rosa, P.A., Falini, A., Perani, D., Cappa, S.F., &

Moro, A. (2008). Negation in the brain: Modulating action representations.

NeuroImage 43, 358-367.

Tian, Y., Breheny, R., & Ferguson, H.J. (2010). Why we stimulate negated information:

A dynamic pragmatic account. Quarterly Journal of Experimental Psychology,

63, 2305-2312.

References

148

Trabasso, T., Rollins, H., & Shaughnessy, E. (1971). Storage and verification stages in

processing concepts. Cognitive Psychology, 2, 239-289.

Von Eckardt, B. (1993). What is Cognitive Science?. Cambridge, MA: The MIT Press.

Wang, J., Conder, J.A., Blitzer, D.N., & Shinkareva, S.V. (2010). Neural representation

of abstract and concrete concepts: a meta-analysis of neuroimaging studies.

Human brain mapping, 31, 1459-1468.

Warrington, E. K. & Crutch, S. J. (2007). Semantic refractory access disorders. In

J.J.Hart & M. A. Kraut (Eds.), The Neural Bases of Semantic Memory (pp. 3-27).

Cambridge: Cambridge University Press.

Wason, P.C. (1959). The processing of positive and negative information. Quarterly

Journal of Experiment Psychology, 11, 92-107.

Wason, P.C. (1961). Response to affirmative and negative binary statements. British

Journal of Psychology, 52, 133-142.

Wason, P.C. (1965). The contexts of plausible denial. Journal of Verbal Learning and

Verbal Behavior, 4, 7-11.

Wason, P.C. (1972). In real life negatives are false. Logique et Analyse 15, 17-38.

Wason, P. C., & Johnson-Laird, P. N. (1972). Psychology of reasoning: Structure and

content. Cambridge, MA: Harvard University Press.

Wason, P.C., Jones, S. (1963). Negatives: denotation and connation. British Journal of


Watson, J. M. (1979). Referential description by children in negative form. British

Journal of Psychology 70, 199-204.

Wilson, D. & Sperber, D. (2004). Relevance theory. In L.R. Horn, & G. Ward (Eds.),

The Handbook of pragmatics (pp. 607-632). Oxford: Blackwell.

References

149

Wiswede, D., Koranyi, N., Müller, F., Langner, O., & Rothermund, K. (2012).

Validating the truth of propositions: behavioral and ERP indicators of truth

evaluation processes. Scan, 1-7.

Wittgenstein, L. (1953). Philosophical investigations. New York: The MacMillan

Company.

Young, R., & Chase, W.G. (1971). Additive stages in the comparison of sentences and

pictures. Paper presented at Midwestern Psychological Association meetings,

Chicago.

Zdrazilova, L., & Pexman, P. M. (2013). Grasping the invisible: Semantic processing of

abstract words. Psychonomic Bulletin & Review.

Zwaan, R.A., & Radvansky, G.A. (1998). Situation models in language comprehension

and memory. Psychological Bulletin, 123, 162-185.

Zwaan, R.A., Stanfield, R.A., & Yaxley, R.H. (2002). Language comprehenders

mentally represent the shapes of objects. Psychological Science, 13, 168-171.

EL CURSO TEMPORAL DE LA NEGACIÓN: · PDF fileEL CURSO TEMPORAL DE LA NEGACIÓN:...

Documents

Transcript of EL CURSO TEMPORAL DE LA NEGACIÓN: · PDF fileEL CURSO TEMPORAL DE LA NEGACIÓN:...