Learning

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Chapter 6
Learning
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Learning
Learning –
A lasting change in behavior or
mental processes that results from
experience
(Habituation)
Learning
Mere exposure effect
Behavioral learning –
(e.g. classical and operant conditioning)
Pavlov’s Dogs

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“Real” founder of Behaviorism
Russian physiologist & Nobel Prize Winner
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
The stimulus that elicits
an unconditioned
response
Examples of
Unconditioned Stimuli


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

food
loud noise
light in eye
puff of air in
touching hot stove
salivation
startle
pupil contraction
eye blink
hand withdrawal
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
The response elicited
by an unconditioned
stimulus without prior
learning
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
A previously neutral
stimulus that comes to
elicit the conditioned
response
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
A response elicited by a
previously neutral
stimulus that has
become associated with
the unconditioned
stimulus
Classical Conditioning
Prior to conditioning
Neutral stimulus
(tone)
(Orientation to sound
but no response)
UCS
(food powder in mouth)
UCR
(salivation)
Conditioning
Neutral stimulus
CS (tone)
+
UCS
(food powder)
CR
(salivation)
After conditioning
CS
(tone)
CR
(salivation)
Learning to
Fear

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
Research suggests we can learn fear
through association.
Watson and Raynor conditioned “Little
Albert” to be afraid of white rats
Within days, Albert’s fear had
generalized to other furry objects.
Acquisition, Extinction, and
Spontaneous Recovery
Conditioned Taste Aversions
Taste-aversion learning –
Biological tendency where an
organism learns to avoid food
One trial learning*
How Do We Learn Behaviors by
Operant Conditioning?
Trial-and-error learning –
Learner gradually discovers the
correct response by attempting
many behaviors
Thorndike’s Puzzle Box
http://fates.cns.muskingum.edu/~psych/psycweb/history/thorndike.htm#Theory
Thorndike’s law of effect


The consequence, or effect, of a response will
determine the tendency to respond in the same
way in the future (strengthened or weakened).
Satisfying vs. Unsatisfying consequences
(No consequences)
Thorndike builds a Foundation


Thorndike (1898) insisted that it was
“unnecessary to invoke reasoning” to
explain how the learning took place.
Thorndike’s law of effect formed the
conceptual starting point for Skinner’s
work in operant conditioning.
The Skinner Box
The Power of Reinforcement
Positive reinforcers –
Stimulus presented after a response
that increases the probability of that
response happening again
Negative reinforcers –
Removal of an unpleasant stimulus
The Problem of Punishment
Punishment –
An aversive stimulus which decreases
the probability of the response it
follows
How does this differ from
negative reinforcement?
Punishment vs. Negative
Reinforcement
Negative
Reinforcement
Response
Consequence
Loud Noise
Press Lever
Loud Noise
Removed
Press Lever
Loud Noise
Applied
Punishment
No Noise
Four Kinds of Consequences
Increase
Behavior
Decrease
Behavior
Positive Stimulus
(Add)
Negative Stimulus
(Subtract)
Positive
Reinforcement
Negative
Reinforcement
Bonus for working
hard leads to more
hard work
Headache gone
after aspirin leads
to more aspirin use
Positive
Punishment
Negative
Punishment
Getting speeding
ticket leads to less
speeding
No Television leads
to less staying out
late
When Punishment Fails



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
Teaches poor behavior not good behavior
Recipient responds with negative emotion
(anxiety, fear, rage, distrust).
The effectiveness is often temporary.
Punishment conveys little information.
An action intended to punish may instead be
reinforcing.
More effective if* (Swift, Consistent,
Sufficient, with explanation)
Alternatives to Punishment

Extinction

Reinforcing preferred activities

Premack principle
• Prompting and shaping
Final Comments-Shaping Behavior
Schedules of Reinforcement
Ratio schedules –
Provide reward after a certain number of
responses
Interval schedules –
Provide reward after a certain time interval
Fixed Ratio (FR)
Variable Ratio (VR)
Fixed Interval (FI)
Variable Interval (VI)
Benefits of Partial Reinforcement
Social Learning: Challenge
to Behaviorism
Social learning –
Form of cognitive learning where new
responses are acquired by watching
(and the consequences)
(Albert Bandura)
Adult Model
Children’s Behavior
Kids Who Watch Lots of TV:
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Have higher petty delinquency
More likely to be in serious fights/or to
hurt someone badly
Conflicts with parents that include fighting
Perceive aggression to be effective and
are more willing to use physical force
Intrinsic and Extrinsic
Reinforcement

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
Intrinsic reinforcement is reinforcement provided
by the mere act of performing the behavior.
Extrinsic reinforcement is reinforcement provided
by some consequence that is external to the
behavior.
External reinforcers may undermine internal
reinforcers**
Are Rewards always
reinforcing?
Overjustification effect –
The process by which extrinsic rewards can
sometimes displace internal motivation
-informative
value vs.
random consequence
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