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Pomona College

LCS 11: Cognitive Science

Behaviorism

Jesse Harris Module 2, Class 1

Jesse Harris: LCS 11: Cognitive Science, Behaviorism 1

Agenda

֠ Discussion of writing response #1 ֠ Background to behaviorism handout ֠ On conditioning ֠ Module 1 evaluations ֠ Next class

• 1. Physicalism: Cunningham, 2000, pp. 21-31;

Ramachandran, 2005, ch 1–2

• 2. GQ 2.1 due Tuesday by 9PM

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Writing response #1

So far in this class, we’ve looked at evidence that the mind is composed of two very different sort of mechanisms: highly modular mechanisms that specialize in particular kinds of tasks, and more general sorts of mechanisms, e.g., neural nets. We’ve also discussed the (limited) role of consciousness in cognition. In 1-2 single spaced pages, I’d like you to speculate on how consciousness fits into the picture we’ve developed so

• far. In your opinion, is consciousness more like a module, a domain general

mechanism, or something else entirely? Defend your view with a concrete argument and examples from the reading or elsewhere. Cite all references where appropriate.

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On the mind-body problem

The behaviorist’s question

Why not just study the behavior of the organism? Why do we need a concept of mind? The time honored relics of philosophical speculation need trouble the student of behavior as little as they trouble the student of physics. The consideration of the mind-body problem affects neither the type of problem selected nor the formulation of the solution

• f that problem.

(Watson, 1913)

◮ Instead, study reflexual or habitual responses to stimuli

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Classical (Pavlovian) conditioning: aims

Goal of classical conditioning

Turn the unconditioned response (UR) into a conditioned response (CR) by pairing the conditioned stimulus (CS) with the experience of getting the unconditioned stimulus (CS). US Unconditioned stimulus food UR Unconditioned response salivation CS Conditioned stimulus ringing bell CR Conditioned response salivation

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Classical (Pavlovian) conditioning: method

◮ Collected salivary

secretions of dogs

◮ Tube inserted into ducts

• f salivary glands

◮ Saliva collected into

measuring cylinder

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Classical (Pavlovian) conditioning

US Unconditioned stimulus food UR Unconditioned response salivation CS Conditioned stimulus ringing bell CR Conditioned response salivation food > salivation bell ∧

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Classical (Pavlovian) conditioning

US Unconditioned stimulus food UR Unconditioned response salivation CS Conditioned stimulus ringing bell CR Conditioned response salivation salivation bell >

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Little Albert

Introduction of fear

◮ Responses like a fear can be

manufactured, provided that appropriate pairings are introduced

http://www.youtube.com/watch?v=Xt0ucxOrPQE#t=54s

John B. Watson

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• B. F. Skinner

Aims of behaviorism

• 1. Methodological reduction
• 2. A descriptive science of behavior
• 3. Non-theoretical science, more

like engineering

• 4. How to build and predict

behavior in society

http://www.youtube.com/watch?v=LSv992Ts6as#t=2m33s

• B. F. Skinner

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• B. F. Skinner

The psychology “of the empty

• rganism”

◮ Facts of behavior are

independent of questions of mind

◮ If there were nothing to

• rganisms, still behavior

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Behaviorist dictates

Avoid mentalistic terms

Don’t presuppose an independent, private mental life that can

• nly be communicated by the subject

Operational definitions

Define terms by reference to the operations or method you would use to realize or produce what that term is referring to

◮ Hunger – defined by to some other objective measure,

e.g., hours of food deprivation, rather than a subjective term

• Keep constant across lab settings
• All in observable world
• Behavior is a response to events in the environment

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Behaviorists on love

◮ Studies in 1950’s defined love as

the total number of hours in a day that one was physically close to the object of love.

◮ Failure to operationalize more

advanced behavior and relations

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Skinner box

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Reinforcement

Continuous reinforcement

Every bar press results in reinforcer

◮ Operational definition: A stimulus is a reinforcer when it

alters the probability of the behavior that produces it

• Positive reinforcer - increases the probability
• Negative reinforcer - lowers the probability

◮ Avoid mentalistic terms: Animal’s behavior that defines

the reinforcer, not some estimate of its mental state.

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Reinforcement

◮ Eats nearly its own weight in

food

◮ To cut down on costs, Skinner

rewarded the pigeon at every

• ther peck
• Animal quickly learns to peck

twice

• And so on for each action to

reward ratio

Partial reinforcement

Only some responses are enforced; schedules of reinforcement

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Random reinforcement

Schedule of reinforcement

Stretch out how many responses are required for payoff; in extreme case, randomly determine what the schedule of reinforcement is for each trial

◮ Maintain stable rates of behavior across a lifetime ◮ Never know when to stop pulling the lever ◮ No determined cue for delivery ◮ Can you think of an example of this in human behavior?

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Random reinforcement

http://www.youtube.com/watch?v=yhvaSEJtOV8#t=1m25s

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Behavior and the mind

Open questions

• 1. What is the connection between behavior and mind?
• 2. Can we do away with all talk of mentalistic terms?
• 3. What sorts of behavior do we fail to capture?

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Next time: Physicalism

Cunningham, 2000: pp. 21–31 Ramachandran, 2005: ch. 1–2

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GQ 2.1 - due Feb 12, by 9PM

On any type of Physicalism that Cunningham (2000, pp.21-31) discusses, mental phenomena should be strongly associated with, or even reduce to, some sort of physical state in the brain. Take any ONE of the unique disorders described in Ramachandran (2005) in chapters 1-2, which includes Capgras syndrome, phantom limbs, synesthesia, blindsight, anosognosia (lack of insight), etc., in which damage to the brain is associated with specific behavioral deficits, and briefly relate the patients’ particular experience to the physicalist viewpoint. In other words, are the unique experiences expected or supported under Physicalism? Why or why not? Group leaders: Devin, Tatiana, Sierra, Audrey, Jun, Hana, Lea Lynn, Ally, Becca

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