Download LCS 11: Cognitive Science - Behaviorism

Agenda
Pomona College
LCS 11: Cognitive Science
Behaviorism
Jesse Harris
Module 2, Class 1
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Writing response #1
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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On the mind-body problem
The behaviorist’s question
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.
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
of that problem.
(Watson, 1913)
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Instead, study reflexual or habitual responses to stimuli
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Classical (Pavlovian) conditioning: aims
Classical (Pavlovian) conditioning: method
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
UR
CS
CR
Unconditioned stimulus
Unconditioned response
Conditioned stimulus
Conditioned response
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food
salivation
ringing bell
salivation
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Classical (Pavlovian) conditioning
Unconditioned stimulus
Unconditioned response
Conditioned stimulus
Conditioned response
food
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Classical (Pavlovian) conditioning
food
salivation
ringing bell
salivation
US
UR
CS
CR
Unconditioned stimulus
Unconditioned response
Conditioned stimulus
Conditioned response
> salivation
food
salivation
ringing bell
salivation
salivation
bell
bell
Jesse Harris: LCS 11: Cognitive Science, Behaviorism
Jesse Harris: LCS 11: Cognitive Science, Behaviorism
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US
UR
CS
CR
Collected salivary
secretions of dogs
Tube inserted into ducts
of salivary glands
Saliva collected into
measuring cylinder
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Little Albert
B. F. Skinner
Aims of behaviorism
Introduction of fear
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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
Responses like a fear can be
manufactured, provided that
appropriate pairings are
introduced
http://www.youtube.com/watch?v=Xt0ucxOrPQE#t=54s
http://www.youtube.com/watch?v=LSv992Ts6as#t=2m33s
John B. Watson
B. F. Skinner
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B. F. Skinner
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Behaviorist dictates
Avoid mentalistic terms
Don’t presuppose an independent, private mental life that can
only be communicated by the subject
The psychology “of the empty
organism”
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Operational definitions
Define terms by reference to the operations or method you
would use to realize or produce what that term is referring to
Facts of behavior are
independent of questions of
mind
If there were nothing to
organisms, still behavior
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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
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Skinner box
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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Reinforcement
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Reinforcement
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Continuous reinforcement
Every bar press results in reinforcer
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Operational definition: A stimulus is a reinforcer when it
alters the probability of the behavior that produces it
Eats nearly its own weight in
food
To cut down on costs, Skinner
rewarded the pigeon at every
other peck
• Animal quickly learns to peck
twice
• And so on for each action to
reward ratio
• Positive reinforcer - increases the probability
• Negative reinforcer - lowers the probability
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Avoid mentalistic terms: Animal’s behavior that defines
the reinforcer, not some estimate of its mental state.
Partial reinforcement
Only some responses are enforced;
schedules of reinforcement
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Random reinforcement
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
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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?
http://www.youtube.com/watch?v=yhvaSEJtOV8#t=1m25s
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Behavior and the mind
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Next time: Physicalism
Cunningham, 2000: pp. 21–31
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?
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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