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PSY 402
Theories of Learning
Chapter 7 – Behavior & Its Consequences
Instrumental & Operant Learning
Two Early Approaches
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Reinforcement Theory
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Thorndike’s “Law of Effect” for cats in the puzzle
box.
Skinner boxes – rats pressing bars
Contiguity Theory
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Guthrie – association is enough
Estes – Stimulus Sampling Theory
Problems with Contiguity Theory
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Guthrie proposed that no reinforcement was
needed – just contiguity (closeness) in time
and place.
If learning is immediate and one-trial, why are
learning curves gradual?
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Only a few stimulus elements are associated on
each trial, but more build up with each trial.
His view was wrong but influential (Estes).
7.1 Learning as Guthrie saw it
Guthrie & Reinforcement
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The reinforcer is salient, so it changes the
stimulus (environmental situation).
Reward keeps competing responses from
being associated with the initial stimulus.
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Competing responses are instead associated with
the presence of the reward.
Fixity of cat flank-rubbing supported Guthrie
but was later shown to be related to the
presence of the experimenter instead.
7.2 The effect of reward as Guthrie saw it
This is
grooming
Grooming becomes
associated with start area
because rat did it last.
Grooming is associated with
start area that is associated
with reward
Grooming is not
associated with start
area, so rat goes to
goal area instead of
grooming.
Tolman’s Operational Behaviorism
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His theories relied on “intervening variables”
not mechanistic S-R associations.
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Behavior is motivated by goals.
Behavior is flexible, a means to an end.
Rats in mazes form cognitive maps of their
environment.
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Animals learn about stimuli, not just behavior.
Evidence of Cognitive Maps
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Changing the maze layout resulted in running
toward the same “goal.”
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A light could have been used as a cue in both
situations.
Using a “plus maze,” some rats were trained
to always turn a certain direction, while others
were trained to reach a consistent place.
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The consistent place was easier to learn.
7.3 Bird's eye view of the apparatus used by Tolman, Ritchie, and Kalisch
7.4 Maze with two start and two goal locations for place and response learning
Latent Learning
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Rats were given experience in a complex
maze, without reward.
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Later they were rewarded for finding the goal
box.
Performance (number of errors) improved greatly
with reward, even among previously unrewarded
rats.
Reward motivates performance, not learning.
7.5 Latent learning experiment: The 14-unit T-maze (Part 1)
7.5 Latent learning experiment: The results (Part 2)
Skinner’s Contribution
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Skinner was uninterested in theory – he
wanted to see how learning works in practice.
Operant chambers permit behaviors to be
repeated as often as desired – more voluntary.
Superstitious behavior – animals were
rewarded at intervals without regard to their
behaviors.
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Animals related whatever they were doing to the
reward, and wound up doing odd things.