PSY402Theories of Learning

Chapter 9 – Contemporary Theories

Cognitive View of Phobia

Bandura – two kinds of expectancy maintain a phobia: Stimulus-outcome expectancy – about

the nature of the stimulus. Response-outcome expectancy – about

the likely result of behavior. Why does phobia produce behavior

with negative outcomes? Efficacy expectancy – belief that one

cannot execute a particular action.

Self-Efficacy

Types of information used to establish self-efficacy: Personal accomplishments, success. Task difficulty, amount of effort. Observations of success/failure of

others – vicarious modeling. Emotional arousal – we feel less able to

cope when agitated or tense. Efficacy predicts approach behavior.

Criticisms of Efficacy View

Efficacy expectations may be epiphenomenal – arise with anxiety but do not affect responding.

Three types of anxiety: Cognitive – affects self-efficacy Physiological – affects physiology Behavioral – affects responding.

Lang – contribution of each depends on prior experience and situation.

Contemporary Theories

Shift from global theories (e.g., Hull’s drive theory) to theories about specific aspects of learning. Global theories were about operant

responding not classical conditioning. An animal’s biology influences whether,

what, and how fast it can learn. Cognitive view requires emphasis on

specific cognitive processes.

Contemporary Theories (Cont.)

Classical Conditioning: Nature of the CR – stimulus substitution

theory and SOP theory Predictiveness of the CS – Rescorla-

Wagner associative model, comparator theory, attentional theory, retrospective processing approach.

Operant Conditioning: Nature of reinforcement Behavioral economics

Stimulus-Substitution Theory

What is the nature of the CR – is it just the UCR or is it different?

Pavlov – stimulus-substitution theory: The CS stimulates the same areas of

the brain as the UCS, producing the same response.

Activation of CS with UCS establishes neural connection between brain areas.

Conditioned Opponent Response

The CR and UCR are often different: CR of fear is different than UCR of pain.

Siegel – best evidence of difference: Morphine (UCS) produced analgesia,

reduced pain (UCR) Light or tone (CS) produced

hyperalgesia, increased pain (CR). Rats remove paws from heat quickly

with CS, slowly with UCS. Insulin (glycemia) works the same way

Drug Tolerance Overdoses

Elimination of a CS results in a stronger response to the UCS, drug. Extinction of responding to environ-

mental cues strengthens drug response Changing the context in which a

drug is administered increases response to the drug. Novel environment does not elicit an

opponent CR.

SOP Theory

Sometimes Opponent-Process theory (SOP) – explains why CR varies.

UCS elicits primary A1 (fast) and secondary A2 (longer) responses. A1 & A2 can be same or different.

Conditioning only occurs to A2 – the CR is always an A2 response. When A1 & A2 differ, UCR & CR differ.

Two-Phase Reactions

Shock – results in: A1 -- Initial agitated hyperactivity A2 -- Long-lasting hypoactivity

(freezing) CER elicited by CS is A2

Morphine – results in: A1 – sedation or hypoactivity A2 – hyperactivity two hours later CR elicited by CS is hyperactivity

More Support for SOP Theory

Rabbit eyeblink mechanisms support the idea of two-phases.

Backward conditioning – learning occurs if the CS is presented just before the peak of the A2 response. Larew – conditioning occurred with a 31

sec lapse but not 60 sec or 1 sec.

Affective Extension of SOP Theory

Why do different A2 responses have different optimal CS-UCS intervals?

Two distinct UCR sequences activate distinct A1 & A2 sequences: Sensory Emotive

These distinct sequences can have different strengths, time scales (latencies), or eliciting CS’s.

Rescorla-Wagner Theory

There is a maximum associative strength between CS and UCS. UCS determines the limit

Strength gained on each training trial depends on prior training. More learning early, less later on

Rate of conditioning varies. Conditioning of a CS depends on

prior conditioning to other stimuli.

UCS Preexposure Effect

If the UCS is encountered without the CS prior to pairing of the two, less learning occurs.

UCS becomes associated with other environmental stimuli (without CS).

Since there is a limit to association strength, some is drained off by such prior associations. CS-UCS association is weakened.

Problems with Rescorla-Wagner

Overshadowing – salient cues have more associative strength. Sometimes a salient cue potentiates

another cue instead of overshadowing. Garcia says cues are indexed. R-W says cues are seen as unitary

stimulus. Unclear which explanation is

correct.

More Problems

CS preexposure effect – appearance of CS without UCS prior to learning weakens learning. Shouldn’t have any effect according to

Rescorla-Wagner theory, but it does. Cue-deflation effect – extinction of a

more salient cue enhances learning for the less salient cue. Should be no change according to R-W.

Comparator Theory

If two CS’s are associated, extinction of one should reduce responding to the other. Sometimes true, other times not.

CS-UCS associations exist for many stimuli but are exhibited only for the strongest. CS’s are judged in relation to each

other.

Attentional View

Mackintosh – learned irrelevance occurs during preexposure of CS.

Animals exposed to a novel stimulus exhibit an orienting response. No orienting with preexposure. Habituation results in failure of

conditioning. Pairing of CS/UCS in novel context

results in learning.

Retrospective Processing

Most theories assume the level of responding will be constant after learning.

Baker & Mercier suggest association can change after learning. Retrospective processing – CS-UCS

contingency reevaluated after learning. Backward blocking – support for theory Suggests animals have mental

representations, memory for events.

Retrospective Processing

Most theories assume the level of responding will be constant after learning.

Baker & Mercier suggest association can change after learning. Retrospective processing – CS-UCS

contingency reevaluated after learning. Backward blocking – support for theory Suggests animals have mental

representations, memory for events.

Operant Conditioning

Nature of reinforcement: Premack’s probability differential

theory Response deprivation theory

Behavioral economics: Behavioral allocation – blisspoint Choice behavior – Herrnstein’s

matching law. Momentary maximization theory Delay-reduction theory

Probability-Differential Theory

Premack – a reinforcer can be any activity that is more likely to occur than the reinforced behavior. Manipulators vs eaters

High probability behaviors can be used as reinforcers of low probability behaviors. Frequency of the reinforcer decreases

when it is made contingent on another response.

Response Deprivation Theory

Timberlake & Allison – deprivation occurs when an activity is used as a reinforcer and is not freely emitted. The activity is reinforcing because it

satisfies the deprivation created. The animal tries to return to its pre-

deprivation level of responding. Activities can be reinforcing even if

their baselines were not higher.

Behavioral Allocation

Blisspoint (paired basepoint) – the free operant level of two responses. Unrestricted responding with two

choices of behaviors. Blisspoint is used to figure out how

much behavior an animal will engage in to obtain a reward.

Animals try to get as close to the blisspoint as possible.

Problems with Contingencies

Blisspoint is established by looking at behavior before a contingency is established.

The established contingency must take blisspoint into account or it may not increase desired behavior.

Choice Behavior

Herrnstein’s matching law – describes how animals act when they have two or more choices. Different responses have different

schedules of reinforcement. Responding to each choice is

proportionate to the reinforcement for each choice – after learning.

This can be expressed mathematically.

Delayed Gratification

Why does anyone choose a smaller reward part of the time? Animals and people typically choose a

small immediate reward over a larger delayed reward.

Large rewards are selected when: The choice is made in advance of

reward. Reinforcers are not visible or reward is

already present (pleasurable activity).

Complexities of the Matching Law

Maximizing law – sometimes the aim is to obtain as many rewards as possible. Explains FR-10 vs FR-40 schedules. Doesn’t work for VI vs VR schedules.

Momentary maximization theory – choose best alternative at the time.

Delay reduction theory – choose what will get the reward the fastest.