Classical Conditioning – Ch. 4

September 14, 2005Class #10

Experimental Neurosis A condition involving disturbed

behavior in animals that results when they are subjected to severe and prolonged conflict

Pavlov’s Experiments

Pair a circle with food presentations and an ellipse with no food

After the discrimination is formed, the stimuli are made more and more similar until subject can no longer distinguish between the two shapes

Dogs becomes agitated, barks, salivates, bites at its harness, and generally goes berserk

When placed back in the kennel, it may remain "insane" for months or years

Pavlov believed that experimental neurosis resulted from a conflict between excitation and inhibition and occurs when an impossible problem is posed

Real World Application

Pavlov felt that “shy” dogs were the easiest to condition but developed high anxiety when subjected to these neurosis experiments How about with people??? Can they be conditioned to withdraw from

stimulation? The following slide proposes a

behavioral/biological link…

Real World Application

Eysenck (1957): Extraversion-Introversion

Introverts were over-aroused individuals therefore they try to keep stimulation to a minimum

Extroverts were under-aroused individuals, therefore they tried to increase stimulation

Cortical Arousal Differences

Geen (1984) Introverts and extraverts choose different

levels of stimulation, but equivalent in arousal under chosen stimulation

Extroverts chose to hear louder noises than introverts

After put in their chosen environment their HR’s are the same

This seems to suggest that being at their preferred level of stimulation results in the same overall level of arousal for both groups

Geen (1984)

Researcher tested four other groups: Introverts placed in environment that other

introverts had chosen (II) Introverts placed in environment that

extroverts had chosen (IE) Extroverts placed in environment that other

extroverts had chosen (EE) Extroverts placed in environment that

introverts had chosen (EI)

Geen (1984) II = similar HR as free choice introverts IE = higher HR than free choice

introverts when forced to listen to extroverts’ noise

EE = similar HR as free choice extroverts

EI = lower HR than free choice extraverts when forced to listen to introverts’ noise

Geen (1984)

Performance on a learning task was also affected: Introverts did best in introvert-selected

environment Extraverts did better in extravert-selected

environment Practical implications:

Roommates? Mate Selection?

Overshadowing

Involves a compound stimulus (simultaneous presentation of two or more stimuli)

The stronger part of this is more easily conditioned and thus interferes with the conditioning of the other

Overshadowing Experiment

UCS ------------------------------------------- UCR(food) (salivation)

  NS1/NS2 ------------------------------------ NO RESPONSE

(bright light) (soft tone) (no salivation)  NS1/NS2 + UCS ----------------------------- UCR* This is repeated several times…

 CS1 --------------------------------------------- CR(bright light) (much salivation)

CS2 --------------------------------------------- CR(soft tone) (less salivation)

Latent Inhibition

A familiar stimulus is more difficult to condition than an unfamiliar or novel one For example:

If we are used to hearing something it will take longer to condition that sound

You are constantly playing Dave Matthews Band songs…many associations

But a Barry Manilow song may work better…only one association

Real World Application

Schizophrenia patients have less latent inhibition

Additional Phenomena

Temporal Conditioning Occasion Setting External Inhibition US Revaluation Pseudoconditioning

Temporal Conditioning

Passage of time is also important insofar as conditioning is concerned… Example: MLB umpires

Occasion Setting

Elements in the environment plays a big part in the conditioning Example: Presence of alcohol can signal

abuse

External Inhibition

Presentation of a novel stimulus at the same time as the CS lessens the CR

Appears to cause a distraction

US Revaluation

Postconditioning presentation of US at a different intensity

Pseudoconditioning

An elicited response that appears to be a CR may be due to sensitization For example: any loud noise may elicit the

response