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Theoretical Approaches and
questions in Operant
Conditioning
Psychology 3306
Responses and reinforcers
How important are responses and
reinforcers?
 Thorndike and Skinner would say that it is
essential
 Tolman said ‘umm, not completely
 Cognitive maps
 Latent learning
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So you don’t need a reinforcer?
Perhaps it strengthens the S-R bond, but
is not necessary
 Maybe it becomes part of a
representation?
 Colwill and Rescorla, 1985
 Chain - > water
 Lever - > food
 Food - > poison
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That sound you hear is Skinner
spinning in his grave
Rats won’t press the lever!
 Therefore, the response and reinforcer
have been connected, but not directly
 It seems that associations are made
between all three parts of the three term
contingency
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Are there 2 types of learning?
Yes, operant and classical
 No, it is all associative learning
 What a stupid question….
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Pushing the limits
Heart rate conditioning
 Biofeedback
 Not always successful
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So what is a reinforcer?
Some event that increases the likelihood
of….
 ENOUGH!
 Maybe it is need or drive reduction?
 Premack’s ideas
 Is food the reinforcer, or is it the act of
eating?
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Premack’s principle
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Given 2 responses arranged in an
operant-conditioning procedure, more
probable behaviors will reinforce less
probable behaviors; less probable
response will not reinforce more probable
ones
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Premack (1963) - study in Cebus monkeys
Lever Pressing (L) : highest probability
Door Opening (D) : medium probability
Plunger Pulling (P) : lowest probability
reinforces D; L reinforces P; P does NOT
reinforce either D or L, etc.
“Premackian reinforcers”: activities that act as
reinforcers (reading, playing)
Useful (and less costly) in token economies than
object-based reinforcers
Applications
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Mitchell & Stoffelmayr (1973) use Premack’s principle in
schizophrenics
Reinforcement items like candy, cigarettes, etc. usually
not effective in schizophrenic patients
Sitting is a highly probable behavior in negativesymptom schizophrenics (catatonia, social withdrawal)
therapists made sitting contingent on doing small amount
of work or activity; improved their negative symptoms
In unruly nursery-school children, high probability
behaviors (running around, screaming) made contingent
on low probability behaviors (sitting quietly, paying
attention)
Behavioural economics
Open economies
 Closed economies
 Elasticity of demand
 And behavioural ecology
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Stimulus Control
Relationship between S and R
 Reynolds (1961) - Attention in the pigeon
 2 pigeons reinforced for pecking to
compound stimulus of white triangle on
red background
projected on response key
 rate of pecking was then observed in each
subject to a white triangle and a red
background singularly
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Why do you get a gradient?
Sort of the study of generalization and
discrimination
 How do you get data?
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Probe trials
 Test phases
 Both done in extinction
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Is it a property of the nervous system?
Pavlov
 Hubel and Wiesel
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Perhaps it is learning?
Lashley and Wade figured it was how the
animal was trained
 Borne out by Jenkins and Harrison’s work
 Non differential
 Presence absence
 Explicit training
 Peterson (1960) and his ducklings, only
saw yellow
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Duck you
They did not show gradients with colour!
 Oops
 Probably depends on the modality and the
species being tested really
 Or, could be relational Kohler and his
chickens
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Gonzalez, Gentry, & Bitterman (1954) - chimpanzee had
to pick among 9 squares of varying sizes
Squares 1,5, & 9 presented, subject reinforced for
choosing # 5 (intermediate size)
on test trial chimp reinforced no matter which square
chosen
if given 4, 7, & 9 relational theory says subject will
choose # 7, absolute theory says subject
will choose square closest # 5 ( # 4)
subjects usually chose the intermediate size square of
whichever three squares were presented
Peak Shift
OK, so that is odd
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Why does that
happen?
Excitatory gradient
Inhibitory grandient
As the Violent
Femmes would say,
you gotta add it up
Bird brain is not an insult
Concept learning
 Natural needed?
 How long lasting
 Delius (1982)
 Honig and Stewart (1988)
 The field of comparative cognition really
grew out of much of this stuff
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