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PSY402 Theories of Learning
Chapter 11 – Cognitive Control of Behavior
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Purposive Behaviorism
Tolman – behavior is goal-oriented. Through experience we gain expectations about how to use paths and tools to achieve goals. We expect specific outcomes to follow specific behaviors. If unrewarded, we seek other ways to accomplish our goals.
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Tolman’s View (Cont.) We do not have to be reinforced in order to learn. We must be motivated: Motivation produces internal tension creating a demand for the goal. Motivation determines what features of the environment will be noticed. Behavior is not fixed, automatic or stereotyped, but flexible.
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Place-Learning Studies
Demonstrate existence of spatial expectations. T-Maze – rat starts at different location but reward always in same end of maze. Rats must turn different directions. Alternate-path maze – rats choose the shortest path after learning. When blocked, take next shortest path.
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Tolman’s Mazes S2 curtain F2 F1 curtain S1
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Latent-Learning Studies
Investigate whether reward is necessary for learning to occur. Three conditions: R –always got reward at goal NR –never got reward at goal NR-R – rewarded only on last 10 days NR-R rats show rapid decrease in errors when rewarded -- motivation is needed for performance.
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Latent Learning Results
NR R NR-R
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Problems with Latent-Learning
Difficulty replicating results: MacCorquodale & Meehl found 30 of 48 studies could reproduce the results. Motivation restricts attention to relevant cues. Irrelevant rewards are ignored. No latent learning occurs when strong but irrelevant rewards are provided, even if they are relevant later (e.g., water in hungry rat’s maze).
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Drive Response Consistent latent learning occurs when rats are not deprived initially. Spence’s anticipatory goal response, rG-sG was created to explain this result. The anticipatory goal response is formed but not apparent until there is deprivation to activate the goal. Handling animals may have been a reward for Tolman’s NR-group.
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Expectancies Expectancy –mental representation of event contingencies.
Dickinson – an expectancy contains two kinds of information: Associative link between two events – classically conditioned, mechanistic (automatic, reflexive). Behavior-reinforcer belief – consequences of action, operant, intentional.
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Testing Associative Links
Two groups trained to bar press: One group reinforced with sodium chloride (Na) The other group reinforced with potassium (K) Both tested when deprived of sodium. Irrelevant incentive effect – sodium deprivation activated an associative link for Na rats but not K rats.
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Irrelevant Incentive Effect
K is the irrelevant incentive to rats who are sodium deprived.
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Explaining the Effect Is the irrelevant incentive effect due to reinforcer beliefs or associative links? Four groups: Cue A paired with sucrose (classical cond.) Cue B paired with food (classical cond.) Cue C presented with sucrose reward (operant) Cue D presented with food reward (operant) Trained with hunger but tested with thirst.
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Thirsty Rats Expect Water
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Studies with Adults
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Testing for Beliefs Reinforcer devaluation effect – what happens if the reinforcer is devalued after training? One group got sucrose for bar-pressing (contingently) and food regardless of behavior. The other group got food for bar-pressing (contingently) and sucrose non-contingently. Sucrose was devalued during testing. Bar pressing was decreased when the sucrose was behavior-contingent (sucrose reward).
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Importance of Disgust Devaluation is a two-stage process:
A disgust reaction is associated with the reinforcer (devalued by illness). The reinforcer must be reexperienced (for flavors, not necessary for somatic discomfort). Devaluation of the reinforcer occurs when reexperience activates the associated disgust. Studied using ondansetron – a strong anti-emetic (reduces nausea) and LiCl (illness-inducing).
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Importance of Habits Dickinson acknowledged that habits do exist and can control behavior. Expectancies (behavior-reinforcer beliefs) control actions before habits are established. Behavioral autonomy – control of responding by habit rather than expectancy. Habit prevents decreased responding to a devalued reinforcer for food. Devaluation does not affect alcohol reinforcement
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