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The effects of task complexity on learner–learner interaction

YouJin Kim

Department of English, Liberal Arts Building, BOX 6032, Northern Arizona University, Flagstaff, AZ 86011-6032, USA

Received 8 January 2008; received in revised form 11 February 2009; accepted 11 February 2009

Abstract

Over the past few decades, due to the increasing use of interactional tasks in second language (L2) classrooms, research-ers have become interested in examining the factors affecting the learners’ interactional processes as well as L2 learning.For instance, the Cognition Hypothesis states that requiring L2 learners to engage in complex tasks facilitates L2 learningby promoting interaction, focus on form, and attention to more complex linguistic structures [Robinson, P., 2001a. Taskcomplexity, task difficulty, and task production: exploring interactions in a componential framework. Applied Linguistics22, 27–57; Robinson, P., 2001b. Task complexity, cognitive resources and syllabus design: a triadic framework for exam-ining task influences on SLA. In: Robinson, P. (Ed.), Cognition and Second Language Instruction. Cambridge UniversityPress, Cambridge, pp. 287–318; Robinson, P., 2005. Cognitive complexity and task sequencing: Studies in a componentialframework for second language task design. IRAL 43, 1–32]. The purpose of the current study was to identify the impactof task complexity on the occurrence of language-related episodes (LREs) during task-based interaction in two task types(i.e., picture narration and picture difference tasks). Thirty-four ESL students with two different proficiency levels carriedout four tasks which differed in terms of task complexity and task type. Their interaction was transcribed and analyzed interms of the occurrence and resolution of LREs. The results indicated that the effects of task complexity on the occurrenceof learning opportunities differed depending on task types and learner proficiency. The findings are discussed in terms ofthe theoretical implications for Robinson’s Cognition Hypothesis and pedagogical implications for task-based interactionin L2 classrooms.� 2009 Elsevier Ltd. All rights reserved.

Keywords: Task-based language teaching; Task complexity; Learner–learner interaction; Language-related episodes

1. Introduction

Tasks have been seen as primary instructional tools or building blocks of classroom language learning.According to Winne and Marx (1989), tasks can be used as logical models that elicit what students aredoing in classrooms. For this reason, over the past decades, Second Language Acquisition (SLA) research-ers have paid increasing attention to the use of tasks for both research and pedagogical purposes (e.g.,

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doi:10.1016/j.system.2009.02.003

E-mail address: You.Kim@nau.edu

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Bygate et al., 2001; Crookes and Gass, 1993a, 1993b; Ellis, 2003; Samuda and Bygate, 2008). In particular,as more L2 pedagogical research has shifted towards task-based learning and teaching, with its emphasis onpromoting language development in a learner-centered context, a growing number of L2 interaction studieshave started to examine the benefits of learner–learner interaction during collaborative meaning-orientedtasks.

1.1. Task-based learner–learner interaction in L2 classrooms

Researchers working within the framework of the Interaction Hypothesis of L2 acquisition claim that therange of interactional processes during interactive tasks such as negotiation of meaning, provision of feed-back, and production of modified output would promote L2 development (e.g., Gass and Mackey, 2007; Mac-key, 2007a, 2007b; McDonough, 2004). A construct of language-related episodes (LREs) or focus on formepisodes (FFEs) has been increasingly researched to identify learning in process as well as the cause of L2development within the context of interaction (Gass and Mackey, 2007). That is, previous studies have inves-tigated LREs or FFEs as operationalizations of learning opportunities that arise during task performance(e.g., Leeser, 2004; Swain and Lapkin, 1998; Williams, 2001). Such studies have provided useful informationon the different learner variables which might affect the learning environment during task-based learner-lear-ner interaction – e.g., proficiency in the target language (Iwashita 2001; Kim and McDonough, 2008; Leeser,2004; Watanabe and Swain, 2007; Williams, 1999, 2001; Yule and Macdonald, 1990), gender (Ross-Feldman,2007), age group (Mackey and Silver, 2005; Oliver, 1995), the status of native vs. non-native speaker (Mackeyet al., 2003), level of learner participation (McDonough, 2004) and so on.

Also, due to the increased attention in using collaborative tasks in the L2 classroom, more studies haveexamined a variety of aspects of pedagogic tasks. For instance, studies have focused on the impact of taskvariables on the learners’ oral production such as different task types (Slimani-Rolls, 2005), task complexity(Robinson, 2001a, 2001b; Skehan and Foster, 1999), task planning time options (Ellis, 2005; Foster and Ske-han, 1996) and task repetition (Bygate, 2001; Gass et al., 1999). The construct of ‘‘task complexity”, in par-ticular, has been defined as task sequencing criteria and is also seen as an important factor affecting taskperformance (i.e., fluency, complexity, and accuracy) and the amount of interaction (e.g., Long, 1985; Rob-inson, 2005, 2007a; Skehan, 1996, 1998).

1.2. Task complexity and the Cognition Hypothesis

In his triadic componential framework, Robinson (2001a, 2001b, 2003, 2005) differentiated sources of atask’s cognitive demand in terms of: (1) task complexity-cognitive factors relating to how the task is designed;(2) task conditions-interactional factors regarding participation and participant variables (e.g., two-way vs.one way); and (3) task difficulty-learner factors regarding affective and learner ability variables (e.g., motiva-

Table 1Robinson’s Task Complexity Dimensions (Adapted from Nuevo, 2006).

Task complexity(cognitive factors) Descriptions in picture narration task

(1) Resource-directing

± few elements more pictures (�few elements) vs. fewer pictures to narrate (+few elements)± here-and-now narrate without the pictures (�here and now) vs. narrate with the pictures (+ here and now)± reasoning demands pictures presented in an order (�reasoning) vs. pictures presented in no order (+reasoning)

(2) Resource-dispersing

± planning narrate with planning time (+planning) vs. narrate without planning time (�planning)± single task narrate the pictures (+single task) vs. narrate the pictures and write the story (�single task)± prior knowledge not familiar with the story plot (�prior knowledge) vs. familiar with the story plot (+prior

knowledge)

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tion and working memory). Within his task complexity criteria, he identified two dimensions: resource-direct-ing and resource-dispersing, as described in Table 1.

Robinson (2001a, 2001b, 2003, 2005, 2007a) classified task complexity in terms of cognitive/conceptual(i.e., resource-directing), and performative/procedural (i.e., resource-dispersing) demands. Resource-directingvariables of task complexity make greater demands on attention and working memory in a way that helpslearners to focus on linguistic forms. Examples of resource-directing factors include: [± few elements], [± hereand now], and [± reasoning demand]. As illustrated in Table 1 with the picture narration task, the low com-plexity conditions would be [+ few elements], [+ here and now], and [� reasoning demand], whereas the highcomplexity conditions would be [� few elements], [� here and now], and [+ reasoning demand].

On the other hand, resource-dispersing variables are those that make increased performative/proceduraldemands on participants’ attentional and memory resources, but do not direct them to any particular linguis-tic forms (Robinson, 2001a, 2005). Thus, increasing task complexity along resource-dispersing dimensions dis-perses learner attention over many non-specific linguistics areas of the L2. Examples of resource-dispersingfactors include: [± planning], [± single task], and [± prior knowledge]. To clarify, the low complexity condi-tions would be [+planning], [+single task], and [+prior knowledge], whereas the high complexity conditionswould be [�planning], [�single task], and [�prior knowledge].

Overall, Robinson (2005) argued that predictions about the effects of task complexity in the two kinds ofdimensions (i.e., resource-directing and resource-dispersing) are very different. Building on the cognitive andinteractive perspectives of task-based interaction, the Cognition Hypothesis claims that complex tasks may (1)elicit L2 production characterized by greater accuracy and complexity but less fluency and (2) generate inter-actional processes such as corrective feedback, noticing of input, uptake of forms made salient during inter-action, thereby facilitating subsequent L2 development (2001a, 2003, 2005, 2007a, 2007b).

To date, a growing number of previous empirical studies have tested Robinson’s hypothesis by investigat-ing the role of task complexity in task-based instruction. For instance, these studies used various task com-plexity variables such as [± here and now] (Gilabert, 2005; Robinson, 1995; Robinson et al., 1995), [±reasoning demand] (Iwashita et al., 2001; Lee, 2002; Nuevo, 2006), [± single task] (Robinson, 2007b), and[± few elements] (Kuiken et al., 2005; Kuiken and Vedder, 2007). The majority of previous studies have dis-cussed the relationship between task complexity and L2 production (see Ellis, 2003 for a review), and relativelyfew studies have examined the role of task complexity in interactional processes (i.e., learning opportunities)during learner-learner interaction (Nuevo, 2006; Robinson, 2001a, 2007a).

Robinson (2001a) addressed the impact of task complexity on interaction in addition to L2 production. Hemanipulated task complexity with two variables, [± prior knowledge] and [± few elements] in map tasks. Inpairs, one participant was instructed to give directions from point A to point B to a partner who had onlypoint A on their map. The findings showed that significantly greater interactional processes (i.e., comprehen-sion checks and clarification requests) occurred during the complex version than the simple version of the task.

In a recent study, Nuevo (2006) examined the relationship between L2 learning opportunities and develop-ment depending on task complexity. She focused on two linguistic features (i.e., past tense and locative prep-ositions) and adopted the task dimension [± reasoning demands]. In the pretest–posttest-delayed posttestresearch design, three groups (N = 113) of learners participated in two different tasks, picture narration tasksand decision making tasks with different levels of complexity. The learning opportunities were operationalizedas nine different interactional processes such as recasts, confirmation checks, and metalinguistic talk. The find-ings indicated that different task complexity conditions promoted different types of learning opportunities. Interms of L2 development, the results showed no association between task complexity and L2 learning, counterto the prediction of the Cognition Hypothesis.

Robinson (2007b) examined the effects of task complexity on L2 speech production, interaction, uptake andperceptions of task difficulty. Three picture narration tasks with three degrees of task complexity by manip-ulating [± reasoning demands] were carried out by 42 Japanese university students working in pairs. Thespeaker decided on the correct sequence for the pictures, and then narrated the story to the listener whohad to sequence the pictures based on the order of narration. Robinson analyzed the number of turn taking,clarification requests, and confirmation checks for listener/sequencers on each task version in order to inves-

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tigate the role of task complexity of the picture narration tasks on the extent of interaction and learningopportunities; the findings indicated that task complexity, along with the resource-directing dimension signif-icantly promoted the amount of interaction.

Overall, among the predictions that Robinson made in the Cognition Hypothesis, previous studies havemainly focused on the impact of task complexity on L2 production. Only few studies reviewed previouslyaddressed the interaction but did not provide conclusive support for the Hypothesis. Given that an increasingamount of attention has been paid to the benefits of leaner–learner interaction in L2 classrooms, the relation-ships between task complexity and interaction-driven L2 learning opportunities during collaborative tasksdeserve more attention. The Cognition Hypothesis not only considers the L2 linguistic performance but alsothe interactional processes such as noticing and learning opportunities. Therefore, in order to test his hypoth-esis more thoroughly and highlight the role of task complexity in L2 pedagogy, the impact of task complexityon the occurrence of learning opportunities needs to be further investigated from both theoretical and peda-gogical reasons.

Furthermore, despite a large amount of work investigating learner-learner interaction, very little researchhas addressed the interaction effects between different task variables and learner variables. For instance, pre-vious research studies have generally supported that high proficiency learners produce more LREs than lowproficiency learners (e.g., Leeser, 2004; Williams, 1999). However, whether a similar pattern of results wouldbe found when implementing tasks with different complexity has not been investigated. Such issue motivatesan interesting empirical question that can expand our understanding of using pedagogical tasks in L2 class-rooms. The current study was thus guided by the following question:

Does task complexity impact the occurrence of LREs during task-based interaction between ESL learnersfrom different proficiency levels?

2. Methods

2.1. Participants

The participants were 34 international students, 25 men and 9 women, who were enrolled in the IntensiveEnglish Program at a university in the USA. They came from a variety of countries: China (10), Saudi Arabia(17), Columbia (2), Taiwan (1), Kuwait (2), Iran (1), and France (1). The average age of the participants was21 ranging from 18 to 37 (SD = 3.63). The participants had studied English for an average of 6 years in theirnative countries, and they reported a length of stay in the US ranging from 3 months to 4 years. They weregrouped into two levels of proficiency (low vs. high) based on their enrollment status in the program and theirpaper-based Test of English as a Foreign Language (TOEFL) scores (low: 340–420; high: 440–490).

2.2. Materials

2.2.1. Tasks

The current study used a total number of four interactive tasks. As shown in Table 2, there were two picturenarration tasks and two picture difference tasks whose complexity was manipulated following Robinson’s taskcomplexity framework (1995, 2001a, 2005). Within resource-directing dimensions, the two factors from Rob-inson’s framework that were manipulated were [± reasoning demands] and [± few elements]. Both picture nar-ration and picture difference tasks were designed as two-way tasks which require interaction and expect anoutcome (Pica et al., 1993).

Table 2Description of test tasks.

Task 1 Task 2 Task 3 Task 4

Task type Picture narration Picture narration Picture difference Picture differenceComplexity factor � reasoning + reasoning + few element � few elementComplexity level Simple Complex Simple Complex

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For the two picture narration tasks, which reflect the [± reasoning demands] variable, Task 2 [+ reasoningdemands] was considered a more complex task compared to Task 1 [� reasoning demands] because it requiredthe learners to put the eight pictures in order and create a storyline. In contrast, Task 1 [� reasoning demands]required students to create a story based on ordered pictures. For the two picture difference tasks (Tasks 3 and4), all pictures commonly depicted a typical beach scene. The difference between the two tasks was in the num-ber of elements shown in the picture. For instance, the pictures in Task 3 [+ few elements] included fewer ele-ments, which was considered a less complex task, whereas pictures in Task 4 [� few elements] contained moreelements, which increased the level of complexity.

2.2.2. Questionnaire

In order to examine the learners’ perceptions of the different degrees of task complexity in the two tasktypes, a questionnaire was developed by the researcher. The questionnaire elicited the learners’ perceptionsabout each task in terms of task complexity and learning opportunities (see Appendix A). Likert-scaleresponse items with nine scales were adapted from Robinson (2001a) particularly to assess the followingfor each task: overall perceptions of task difficulty, ratings of stress, perceived ability to complete the task,interest in task content, and motivation to complete these and other tasks. Additional questions which focusedon the learners’ perspectives on the helpfulness of each task and their opinion about working with a partnerwere included in the questionnaire.

2.3. Procedure

The experiment was conducted in five ESL classes during their regular class periods. In each class, the learn-ers were paired randomly, and they kept the same partner for all four tasks. To avoid the ordering effect, theLatin square design was adopted (Gilabert, 2005). Every pair was given 15 min to complete each task. At theend of the 15 min, they were asked to start the new task. After the learners finished all four tasks, the ques-tionnaire was administered.

2.4. Analysis

In order to identify the occurrence of learning opportunities during task-based learner–learner interaction,LREs were determined throughout treatment sessions. A number of previous studies have shown that LREsnot only indicate language learning in process but also demonstrate the positive correlation with L2 learning(see Gass and Mackey, 2007 for a review). For instance, Kim (2008) found that correctly resolved LREsbetween the learners led to the acquisition of new vocabulary. Thus, LREs were chosen as a unit of analysisin the current study for identifying learning opportunities during task performance. They include a variety ofdiscourse functions during learner–leaner interaction, such as requests for assistance, negotiation sequences,explicit and implicit feedback, and incidences when the learners notice a gap between their interlanguageand the target language system (Williams, 1999).

2.4.1. Identification of LREs

The recordings from the learners were transcribed by the researcher. The transcripts were analyzed for theoccurrence of lexical and grammatical LREs. Based on Swain and Lapkin’s (1995) definitions, grammaticalLREs were defined as LREs in which learners discussed grammatical features of English, including verbtenses, word order, preposition use and so on. A grammatical LRE is illustrated in (1).

(1) Grammatical LRE

1. Learner A: She find the money.2. Learner B: No. . . It should be. . . she found the money. . . past3. Learner A: Ah... sorry... she found the money.

Lexical LREs are defined as LREs in which the learners discuss the meaning, pronunciation or spelling oflexical items, as illustrated in (2).

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(2) Lexical LRE

1. Learner A: Is there any sand castle ( )?2. Learner B: Castle ( )?? Let me see. . . I don’t have3. Learner A: Yes.. castle ( )

2.4.2. Resolution of LREsBased on Swain (1998) and Leeser (2004), the resolution of the LREs was determined as follows: correctly

resolved (Type 1), unresolved (Type 2), and incorrectly resolved (Type 3). Correctly resolved is defined as anLRE in which the problem or question is solved correctly through self or other correction, or through the pro-vision of a correct answer to a question, as illustrated previously in (1) and (2). Unresolved is defined as anLRE in which neither learner could solve the problem or knew the answer to the question, as shown in (3).

(3) Unresolved LRE

1. Learner A: What is this?2. Learner B: Sea animal?3. Learner A: No.. not sea animal4. Learner B: I don’t know...

Incorrectly resolved LREs were defined as LREs in which a problem was solved incorrectly or an incorrectanswer was provided to a question, as shown in (4).

(4) Incorrectly resolved LRE

1. Learner A: How do you say this?2. Learner B: Umbrella?3. Learner A: Spelling? I don’t know4. Learner B: u.m.b.r.e.l.a

Interrater reliability was calculated on a subset of the data (20%) by comparing the identification of LREsas well as the resolution of them. There was 91% exact agreement between the two raters for the occurrence ofthe LREs and 90% for the resolution of the LREs.

Any disagreements were resolved through discussion, typically deferring to the rater who had been presentwhen the interaction took place.

3. Results

The research question investigated the relationship between task complexity and the occurrence of LREsproduced by ESL students with different proficiency levels during task-based learner–learner interaction.The current section reports the findings from the two different task types separately (picture narration taskvs. picture difference task). Table 3 illustrates the occurrence of LREs during the picture narration tasks bynine pairs from the low group and eight pairs from the high group.

As illustrated in Table 3, the low group learners produced 46 lexical and 17 grammatical LREs during thesimple picture narration task and 18 lexical and 16 grammatical LREs during the complex picture narrationtask. In the high group, the learners had 12 lexical and 16 grammatical LREs during the simple picture nar-

Table 3Occurrence of LREs by proficiency during picture narration task.

Proficiency Complexity Lexical LREs Grammatical LREs Total

Sum M SD Sum M SD Sum M SD

Low (9 pairs) Simple 46 5.11 3.30 17 1.89 1.37 63 7.00 4.12Complex 18 2.00 1.23 16 1.78 1.40 34 3.78 2.17

High (8 pairs) Simple 12 1.50 1.20 16 2.00 1.85 28 3.50 2.27Complex 20 2.50 1.77 23 2.88 2.53 43 5.38 3.85

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ration task and 20 lexical and 23 grammatical LREs during the complex picture narration task. The results ofthe individual Wilcoxon Signed Ranks tests indicated that the low group learners produced significantly moreLREs during the simple picture narration task than the complex picture narration task (Z = �2.023,P < 0.05). However, the opposite pattern was found among the high group learners. The high group learnersproduced significantly more LREs during the complex picture narration task than during the simple picturenarration task (Z = �2.132, P < 0.05).

In terms of the picture difference tasks, Table 4 presents the occurrence of LREs during two degrees oftask complexity picture difference tasks by the two proficiency groups. Overall, the low group produced ahigher number of LREs than the high group on both simple and complex picture narration tasks. The lowgroup had 79 lexical and 20 grammatical LREs during the simple picture difference task while 137 lexicaland 18 grammatical LREs occurred during the complex picture difference task. For the high group, thelearners produced 53 lexical and 16 grammatical LREs during the simple version of the task while 61 lexicaland 11 grammatical LREs were found during the complex version of the task. The results of the individualWilcoxon Signed Ranks tests indicated that the low group learners produced significantly more LREs dur-ing the complex picture difference task than the simple picture difference task (Z = �2.033, P < 0.05). How-ever, for the high group learners, no significant result was found during the picture difference tasks based onthe degree of task complexity.

Besides the occurrence of LREs, how the learners resolved the LREs in each task was analyzed in threeways: correctly resolved, unresolved, and incorrectly resolved. Table 5 demonstrates that for the picturenarration tasks, the low group learners correctly resolved 54% (34/63) during the simple picture narrationtask and 56% (19/34) during the complex picture narration task. In contrast, the high group learnersresolved 64% (18/28) and 74% (32/43) of LREs correctly during the simple and complex picture narrationtasks, respectively. A similar pattern was found in the picture difference tasks. About 63% (62/99) and66% (155/193) of the LREs were resolved correctly in the simple and complex picture narration tasksby the low group, leaving 21% (simple and complex narratives) unresolved and 16% (simple narrative)and 12% (complex narrative) incorrectly resolved. The high group learners correctly resolved 75% (52/69) and 79% (57/72) of LREs in the simple and complex picture difference tasks, respectively. However,they were not able to resolve 17% (simple picture difference) and 11% (complex picture difference) of theLREs and resolved 7% (simple picture difference) and 10% (complex picture difference) of the LREsincorrectly.

The amount of LREs occurring during the four tasks was positively correlated with the learners’ judg-ment of their learning opportunities during each task. One of the Likert-scale questions on the question-naire asked the learners to indicate the degree of learning opportunities that they had during each task.Fig. 1 illustrates the mean score of each task by the two proficiency levels on a scale of one (no learningopportunity) to nine (a lot of learning opportunities), following Robinson’s original task perception ques-tionnaire (2001a). As shown in Fig. 1, regardless of the proficiency level, both proficiency groups indicatedthat the complex picture difference task provided more learning opportunities than any other task. Thisfinding was consistent with the actual number of LREs produced by the learners. Their written responseshighlighted that the learners thought the complex picture difference task was very useful in learning newvocabulary.

To summarize the findings, with regards to the picture narration tasks, the low group had significantly moreLREs during the simple picture narration task than the complex picture narration task. However, the high

Table 4Occurrence of LREs by proficiency during picture difference task.

Proficiency Complexity Lexical LREs Grammatical LREs Total

Sum M SD Sum M SD Sum M SD

Low (9 pairs) Simple 79 8.78 4.84 20 2.22 2.39 99 11.00 4.42Complex 137 15.22 4.58 18 2.00 1.94 155 17.22 5.64

High (8 pairs) Simple 53 6.63 1.19 16 2.00 1.07 69 8.63 1.41Complex 61 7.63 3.89 11 1.38 2.39 72 9.00 5.26

Table 5Resolution of LREs by task and complexity.

Picture narration task Picture difference task

Simple Complex Simple Complex

Sum % Sum % Sum % Sum %

Low Group (9 pairs)

Correctly resolved 34 54 19 56 62 63 103 66Unresolved 21 33 12 35 21 21 33 21Incorrectly resolved 8 13 4 9 16 16 19 12Total LREs 63 34 99 155

High Group (8 pairs)

Correctly resolved 18 64 32 74 52 75 57 79Unresolved 8 29 8 19 12 17 8 11Incorrectly resolved 2 7 3 7 5 7 7 10Total LREs 28 43 69 72

5.2

6.1

7.27.9

6.3 6.2

7.3 7.6

0

1

2

3

4

5

6

7

8

9

Simple Narrative Complex Narrative Simple PD Complex PD

Low group

High group

Fig. 1. Learners’ judgment of the learning opportunities.

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group produced significantly more LREs during the complex picture narration task than the simple picturenarration task. For the picture difference tasks, significantly more LREs were produced during the complexpicture difference task than the simple picture difference task by the low group whereas no difference wasfound by the high group. In terms of the resolution of the LREs, a similar pattern was found during the tasksregardless of task complexity in the two task types, showing that slightly more LREs were resolved correctlyduring the complex version of the tasks.

4. Discussion

The current study examined the effects of task complexity on the occurrence of learning opportunitiesduring two task types by ESL learners with different proficiency levels. According to the CognitionHypothesis, it was hypothesized that increasing task complexity along resource-directing dimensions isexpected to facilitate more interaction and promote more noticing and L2 learning opportunities (Robin-son, 2003, 2005, 2007a). The findings of the current study partially supported the Cognition Hypothesisand highlighted that task types and learner proficiency are important factors affecting the impact of taskcomplexity on L2 learning opportunities. For instance, the low group learners produced significantly moreLREs during the simple picture narration task than the complex picture narration task, which was not pre-dicted by the Cognition Hypothesis. In contrast, the high group learners had significantly more LREs dur-ing the complex picture narration task than the simple picture narration task, which provided support forthe Cognition Hypothesis.

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The findings of the current study are somewhat in line with the previous studies which have providedmixed results with regards to the predictions of the Cognition Hypothesis. Although Nuevo (2006) didnot include different proficiency levels of learners in her study, she found that the learners generally pro-duced more learning opportunities during the simple picture narration task than the complex picture nar-ration task. However, with nine different categories of learning opportunities, she also reported somecontradictory results showing that different task complexity (i.e., reasoning demands) promoted differenttypes of learning opportunities in picture narration tasks. Taking recasts and uptake of recasts into consid-eration, the greater use of recasts and uptake of recasts occurred during the simple picture narration taskthan the complex picture narration task. According to Nuevo, learners engaged in low complexity taskshave more attentional resources available to monitor the output of their peer interlocutor and to providefeedback than learners engaged in high complexity tasks. This might be the reason why the low grouphad more LREs during the simple picture narration task than the complex picture narration task in thecurrent study.

However, the high group learners produced more LREs, especially grammatical LREs during the com-plex picture narration task than the simple picture narration task, which supports the Cognition Hypothesis.That is, along resource-directing dimensions more complex tasks result in a greater amount of interactionand negotiation for meaning. Following Long (1996), such negotiation, which itself is a type of LRE pro-vides a context for attending to problematic forms in the input and output, and additionally that on com-plex versions of tasks there will be greater attention to focus on form techniques such as recasts (Robinsonand Gilabert, 2007). This argument can be supported by the fact that during the complex picture narrationtask, the high group learners produced more grammatical LREs as a form of negative feedback (e.g., recast,explicit correction). As shown in Example (5), the high group learners paid attention to grammatical issuesduring the complex picture narration task, especially focusing on verb tense. In this example, Learner B pro-vided a recast (line 4) for the wrong verb tense used by Learner A. In the subsequent turn, Learner Aresponded to the recast by repeating the reformulated utterance and applied the rule to the next verb ‘‘deci-de” in Line 5.

Example 5: Grammatical LRE by a high group pair

1. Learner A: She was she found the ticket and the ticket was like. . .2. Learner B: concert?3. Learner A: concert? And she win $10, 000.4. Learner B: She won, ah huh?5. Learner A: Yeah.. she won and she decide.. decided to to. . . buy a car for her6. husband yeah. . .what next picture?

The findings related to the resolution of the LREs also supported that more LREs were unresolved duringthe simple picture narration task than the complex picture narration task by the high group learners. Thisresult is similar to Robinson’s (2007b) argument that high complex tasks produced a greater amount of uptakethan the simple and mid complex tasks.

Although the Cognition Hypothesis was not supported with the picture narration tasks by the low group,it was supported with the picture difference tasks. There were significantly more LREs, particularly lexicalLREs with the complex picture difference task than with the simple picture difference task. Based on theCognition Hypothesis, the complex picture difference task whose pictures included more elements (i.e., moreitems on the picture) promoted more interaction and negotiation than the simple picture difference taskwhose pictures included less elements (i.e., less items on the picture). This finding might have been influ-enced by the characteristics of the picture difference task which requires the learners to interact with eachother and specify the object that they are discussing in order to complete the tasks. The picture differencetask requires high attention to the interlocutor’s utterance and thus facilitates the occurrence of interac-tional processes. Consequently, the amount of learning opportunities would easily be influenced by the com-plexity of input on the pictures. For low learners who probably have less vocabulary, the degree of taskcomplexity seems to be more crucial than for the high level learners.

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As illustrated in Example 6, the results showed that the low group learners’ LREs were largely associatedwith vocabulary issues particularly focusing on word meaning, which is consistent with previous LRE studies(e.g., Kim and McDonough, 2008; Leeser, 2004; Williams, 1999). The number of lexical LREs increased fromthe simple version to the complex version of the picture difference task as the number of elements in the pictureincreased. In Example 6, two lexical LREs focusing on the word meaning occurred together when the twolearners discussed the meaning of two vocabulary items, ‘‘digging” and ‘‘shovel.” The LREs focusing onthe word meaning occurred as a form of metalinguistic talk when the learners explicitly asked for assistanceto find out linguistic information such as spelling, word meaning, or finding the word form for objects in thepicture.

Example 6: Lexical LREs by a low group pair

1. Learner A: Do you have a kid on the right of the picture he’s digging?2. Learner B: What?3. Learner A: He’s digging4. Learner B: digging? digging? What digging?5. Learner A: dig...like to make like a hole.6. Learner B: oh.. ok.7. Learner A: digging, right?8. Learner B: digging where. . .. where again like what like he’s position in the picture9. Yeah.. he is on the right of picture with shovel

10. Learner A: Shovel? What is shovel?11. Learner B: use shovel to dig. . .12. Learner A: Ah.. I have one.

The nature of the picture difference tasks that generally required attention to the other learner’s utterancealso affected the occurrence of LREs as a form of negative feedback dealing with pronunciation. In Example 7,Learner B could not understand Learner A’s pronunciation of the word ‘‘cup” which led to a confirmationcheck. The learners produced similar types of LREs more often during the complex version than the simpleversion of the picture difference task. Based on the Interaction Hypothesis, Example 7 describes the benefits ofinteraction in L2 learning in that Learner B received negative feedback from Learner A (lines 2 and 4), andhad opportunities to make use of the feedback by modifying his output. (Gass, 2003; Long, 1996; Mackey,2007b).

Example 7: Lexical LRE focusing on pronunciation by a pair from the low group

1. Learner A: There’s a cup (/kerp/) there’s cup in the beach?2. Learner B: Curp?3. Learner A: Cup (/kerp/)4. Learner B: What’s that?5. Learner A: Cup. drink coffee6. Learner B: Ah.. cup.. no

However, among the high group learners, the task complexity did not significantly affect the occur-rence of learning opportunities, which did not lend support to Robinson’s Cognition Hypothesis. Basedon this finding, it seems that task complexity manipulated by the number of items might not be a sig-nificant factor affecting task complexity for the high group to facilitate production of more learningopportunities.

Overall, the findings of the current study suggested that different task complexity conditions promote dif-ferent amounts of L2 learning opportunities as mediated by task types and learner proficiency. The amount ofLREs occurring during each task supported the learners’ judgments of learning opportunities during the fourtasks, which highlighted the importance of task design to improve learner beliefs about L2 learning duringpedagogic tasks.

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5. Conclusion

To date, the effects of task complexity have been mostly examined with regards to the accuracy, complex-ity, and fluency of L2 speech production. However, given that L2 pedagogic tasks provide learning oppor-tunities in L2 classroom contexts, factors affecting the amount of interactional processes which generatelearning opportunities become fundamental topics for research in the field of task-based language teaching.Based on the Cognition Hypothesis, the current study addressed this issue by investigating the effects of taskcomplexity on the occurrence of LREs with two different task types. Additionally, the study further inves-tigated whether or not learners with different proficiency levels demonstrate similar patterns of LRE produc-tion during two task types with different degrees of task complexity. The findings partially supported theCognition Hypothesis in that significantly more LREs occurred during the complex than the simple versionof the task by the high group learners with the picture narration tasks and by the low group learners withthe picture difference tasks.

The current study has several limitations that should be acknowledged and addressed in future studies. Forinstance, this study cannot be generalized to other educational settings, as a relatively small number of par-ticipants was sampled from one Intensive English Program in the USA. Additionally, the participants inthe current study engaged in each task only once. Long-term data from multiple treatment sections for eachtask would allow for a more definite conclusion regarding the effects of task complexity on the occurrence ofL2 learning opportunities.

The current study included learner proficiency as an individual learner factor, and found that it was animportant factor which potentially mediates the occurrence of LREs during different task types with variousdegrees of task complexity. Additional studies should explore other individual learner factors (e.g., anxietyand aptitude) as well as task factors (e.g., task familiarity and task repetition) which might impact learner–learner interaction in L2 classrooms to find out whether there are any interaction effects with task complexityon the occurrence of learning opportunities. Also, it should be noted that this study included only two distinc-tive task types, the picture narration task and the picture difference task. Future studies might examine othertypes of tasks by manipulating different task complexity variables in Robinson’s framework. Furthermore, thecurrent study operationalized task complexity dichotomously, namely simple vs. complex. However, consid-ering the level of task complexity as a continuum, it is important to investigate multiple levels of task com-plexity. Overall, in order to gain better insights and more pertinent data for the Cognition Hypothesis,there is a need for more experiments that aim to test the hypothesis with a variety of task types which aremanipulated by various degrees of task complexity.

Finally, the purpose of the current study was to identify the occurrence of ‘‘learning opportunities” and notto try to determine L2 development. As Philp et al. (2006) argued, use of corrective feedback or other learningopportunity measures such as LREs should not be treated as the equating term of linguistic development.Therefore the extent to which the occurrence of LREs during the pedagogic tasks lead to the L2 developmentshould be further investigated in future research to address the impact of task complexity on L2 development.To date, research addressing task complexity, and its impact on interactional processes and L2 development isvery scarce. Future studies should continue to expand the scope of the research design such as exploring dif-ferent L2 learning contexts (e.g., different L2 classes) and including classroom-based data over longer periodsof time by using different task types.

In conclusion, the findings of the current study draw pedagogical implications for the use of interactivetasks in L2 classes, particularly as a form of pair work, suggesting that task complexity may have a directimpact on the learners’ interactional processes. Furthermore, the findings of the current study suggestedthat teachers should consider learner proficiency and task types when making a decision on appropriatetask complexity in order to maximize the occurrence of learning opportunities during task-based lear-ner-learner interaction. The current study provides insights on task design and implementation in a varietyof L2 classroom settings, especially among students from a variety of proficiency levels, which will be ofparticular significance to teachers implementing learner–learner interaction within task-based languageteaching, given that there has been an on-going debate concerning the role of learner-learner interactionin L2 learning.

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Acknowledgement:

I would like to thank the anonymous reviewers and Kim McDonough for their helpful and insightful com-ments on earlier drafts of this paper. I am also greatful to Nicole Tracy-Ventura for her great support andvaluable suggestions throughout developing this article.

Appendix A. Questionnaire

Directions: Evaluate each task by circling the appropriate answer in each case

Task 1 (Making a story based on the order of the pictures)

(1)

I thought this task was difficult 1 2 3 4 5 6 7 8 9 I thought this task was easy (2) I felt frustrated doing this task 1 2 3 4 5 6 7 8 9 I felt relaxed doing this task (3) I did not do this task well 1 2 3 4 5 6 7 8 9 I did this task well (4) This task was not interesting 1 2 3 4 5 6 7 8 9 This task was interesting (5) I don’t want to do more tasks like this 1 2 3 4 5 6 7 8 9 I want to do more tasks like this (6) This task did not provide any learning

opportunities

1 2 3 4 5 6 7 8 9 This task provided a lot of learning

opportunities

Task 2 (Making a story after putting the pictures in a right order)

(1)

I thought this task was difficult 1 2 3 4 5 6 7 8 9 I thought this task was easy (2) I felt frustrated doing this task 1 2 3 4 5 6 7 8 9 I felt relaxed doing this task (3) I did not do this task well 1 2 3 4 5 6 7 8 9 I did this task well (4) This task was not interesting 1 2 3 4 5 6 7 8 9 This task was interesting (5) I don’t want to do more tasks like this 1 2 3 4 5 6 7 8 9 I want to do more tasks like this (6) This task did not provide any learning

opportunities

1 2 3 4 5 6 7 8 9 This task provided a lot of learning

opportunities

Task 3 (Finding differences between pictures; less components)

(1)

I thought this task was difficult 1 2 3 4 5 6 7 8 9 I thought this task was easy (2) I felt frustrated doing this task 1 2 3 4 5 6 7 8 9 I felt relaxed doing this task (3) I did not do this task well 1 2 3 4 5 6 7 8 9 I did this task well (4) This task was not interesting 1 2 3 4 5 6 7 8 9 This task was interesting (5) I don’t want to do more tasks like this 1 2 3 4 5 6 7 8 9 I want to do more tasks like this (6) This task did not provide any learning

opportunities

1 2 3 4 5 6 7 8 9 This task provided a lot of learning

opportunities

Task 4 (Finding differences between pictures; more components)

(1)

I thought this task was difficult 1 2 3 4 5 6 7 8 9 I thought this task was easy (2) I felt frustrated doing this task 1 2 3 4 5 6 7 8 9 I felt relaxed doing this task (3) I did not do this task well 1 2 3 4 5 6 7 8 9 I did this task well (4) This task was not interesting 1 2 3 4 5 6 7 8 9 This task was interesting (5) I don’t want to do more tasks like this 1 2 3 4 5 6 7 8 9 I want to do more tasks like this (6) This task did not provide any learning

opportunities

1 2 3 4 5 6 7 8 9 This task provided a lot of learning

opportunities

266 Y. Kim / System 37 (2009) 254–268

Directions: Answer the following questions. Please provide as much detail as possible.

1. Did you like working with a partner for these activities? Circle one Yes No Why?

2. How helpful was it to work with your partner during the task? Choose one.

1) _________Very helpful 2) _________Helpful 3) _________Neither helpful nor unhelpful 4) _________Not so helpful 5) _________Not helpful at all

3. If you found it helpful to work with a partner, which linguistic area did it help? Choose one.

1) _________Vocabulary 2) _________Speaking 3) _________Grammar 4) _____________________________________________________Other (explain)

4. Among the four tasks, which task was the most complex/difficult for you? Circle one Task 1 Task 2 Task 3 Task 4

Why?

5. Among the four tasks, which task was the most interesting for you? Circle one Task 1 Task 2 Task 3 Task 4 Why?

6. Among the four tasks, which task seems to be the most helpful in terms of learning English? Circle one

Task 1 Task 2 Task 3 Task 4 Why?

7. In general, what kinds of activities are helpful to do with a partner instead of doing alone? (e.g., listening exercise, note-taking, vocabulary learning)

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