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Myers’ EXPLORING
PSYCHOLOGY
(4th Ed)
Chapter 6
Learning
James A. McCubbin, PhD
Clemson University
Worth Publishers
Learning
 Learning
relatively permanent change in an
organism’s behavior due to
experience
experience (nurture) is the key to
learning
Association
We learn by association
Our minds naturally connect events that
occur in sequence
Aristotle 2000 years ago
John Locke and David Hume 200 yrs ago
Associative Learning
learning that two events occur together
two stimuli
a response and its consequences
Association
Event 1
Event 2
Sea snail associates splash with a tail shock
Seal learns to expect a snack for its showy antics
Learning to
associate two
events
Classical or Pavlovian
Conditioning
Two related events:
Stimulus 1
Lightning
Stimulus 2
Thunder
Result after repetition
Stimulus
We see
lightning
Response
We wince
anticipating
thunder
We learn to
associate two
stimuli
Operant Conditioning
Response
Stimulus
Response: Pushing
vending machine button
Consequence:Receiving
a candy bar
We learn to
associate a
response and
its
consequence
Classical or Pavlovian
Conditioning
Ivan Pavlov
1849-1936
Russian physician/
neurophysiologist
Nobel Prize in 1904
studied digestive secretions
Classical or Pavlovian
Conditioning
Classical Conditioning
organism comes to associate two stimuli
lightning and thunder
tone and food
begins with a reflex
a neutral stimulus is paired with a stimulus
that evokes the reflex
neutral stimulus eventually comes to evoke
the reflex
Classical or Pavlovian
Conditioning
Pavlov’s device
for recording
salivation
Classical or Pavlovian
Conditioning
Unconditioned Stimulus (UCS)
effective stimulus that unconditionallynaturally and automatically - triggers a
response
Unconditioned Response (UCR)
unlearned, naturally occurring response to
the unconditioned stimulus
salivation when food is in the mouth
Classical or Pavlovian
Conditioning
Conditioned Stimulus (CS)
originally neutral stimulus that, after
association with an unconditioned stimulus,
comes to trigger a conditioned response
Conditioned Response (CR)
learned response to a previously neutral
conditioned stimulus
Classical or Pavlovian
Conditioning
Acquisition
the initial stage of learning, during
which a response is established and
gradually strengthened
the phase associating a neutral stimulus
with an unconditioned stimulus so that
the neutral stimulus comes to evoke a
conditioned response
Classical or Pavlovian
Conditioning
Extinction
diminishing of a conditioned
response
in classical conditioning,
when a unconditioned
stimulus does not follow a
conditioned stimulus
Classical or Pavlovian
Conditioning
Strength
of CR
Acquisition
(CS+UCS)
Extinction
(CS alone)
Spontaneous
recovery of
CR
Extinction
(CS alone)
Pause
Classical or Pavlovian
Conditioning
Spontaneous recovery
reappearance, after a rest period, of
an extinguished conditioned response
Generalization
tendency, once a response has been
established, for stimuli similar to the
conditioned stimulus to evoke similar
responses
Classical or Pavlovian
Conditioning
Discrimination
in classical conditioning, the
ability to distinguish between a
conditioned stimulus and other
stimuli that do not signal an
unconditioned stimulus
Generalization
Drops of saliva
in 30 seconds
60
50
40
30
20
10
0
Pelvis
Hind
paw
Thigh
Shoulder
Trunk
Front
paw
Foreleg
Part of body stimulated
Nausea Conditioning
among Cancer Patients
UCS
(drug)
UCR
(nausea)
CS
(waiting
room)
UCS
(drug)
UCR
(nausea)
CS
(waiting
room)
CR
(nausea)
Behaviorism
John B. Watson
viewed psychology as objective
science
generally agreed-upon consensus today
recommended study of behavior
without reference to unobservable
mental processes
not universally accepted by all schools
of thought today
Little Albert’s Fear
Conditioning
UCS
(loud noise)
CS
(rat)
CS
(rat)
Stimulus similar
to rat (such as
rabbit)
UCR
(fear)
UCS
(loud noise)
CR
(fear)
Conditioned fear
(generalization)
UCR
(fear)
Operant Conditioning
Operant Conditioning
type of learning in which behavior is
strengthened if followed by reinforcement or
diminished if followed by punishment
Law of Effect
Thorndike’s principle that behaviors followed
by favorable consequences become more
likely
Operant Conditioning
Operant Behavior
complex or voluntary behaviors
push button, perform complex task
operates (acts) on environment
produces consequences
Respondent Behavior
occurs as an automatic response to
some stimulus
Operant Conditioning
B.F. Skinner (1904-1990)
elaborated Thorndike’s Law of Effect
developed behavioral technology
Operant Conditioning
Skinner Box
soundproof chamber
with a bar or key
that an animal can
manipulate to obtain
a food or water
reinforcer
contains a device to
record responses
Operant Conditioning
Reinforcer
any event that strengthens the behavior it
follows
Shaping
operant conditioning procedure in which
reinforcers guide behavior toward closer
approximations of a desired goal
Principles of
Reinforcement
Primary Reinforcer
an innate reinforcer
satisfies a biological need
Secondary Reinforcer
a conditioned reinforcer
an event that gains its reinforcing power
through its association with a primary
reinforcer
Schedules of
Reinforcement
Continuous Reinforcement
reinforcing the desired response each time it
occurs
learning occurs rapidly
extinction occurs rapidly
Partial Reinforcement
reinforcing a response only part of the time
results in slower acquisition
greater resistance to extinction
Schedules of
Reinforcement
Fixed Ratio (FR)
schedule that reinforces a response only
after a specified number of responses
the faster you respond, the more
rewards you get
different ratios
very high rate of responding
like piecework pay
Schedules of
Reinforcement
Variable Ratio (VR)
schedule that reinforces a response
after an unpredictable number of
responses
like gambling, fishing
very hard to extinguish because of
unpredictability
Schedules of
Reinforcement
Fixed Interval (FI)
a schedule that reinforces a
response only after a specified time
has elapsed
response occurs more frequently as
the anticipated time for reward
draws near
Schedules of
Reinforcement
Variable Interval (VI)
schedule that reinforces a response
at unpredictable time intervals
produces slow steady responding
like pop quiz
Punishment
Punishment
aversive event that decreases
the behavior that it follows
powerful controller of unwanted
behavior
Problems with
Punishment
Punished behavior is not forgotten, it's
suppressed- behavior returns when
punishment is no longer eminent
Causes increased aggression- shows that
aggression is a way to cope with problemsExplains why aggressive delinquents and
abusive parents come from abusive homes
Problems with
Punishment
Creates fear that can generalize to desirable
behaviors, e.g. fear of school, learned
helplessness, depression
Does not necessarily guide toward desired
behavior- reinforcement tells you what to do-punishment tells you what not to doCombination of punishment and reward can be
more effective than punishment alone
Punishment teaches how to avoid it
Cognition and Operant
Conditioning
Cognitive Map
mental representation of the layout of one’s
environment
example- after exploring a maze, rats act as
if they have learned a cognitive map of it
Latent Learning
learning that occurs, but is not apparent until
there is an incentive to demonstrate it
Operant vs Classical
Conditioning
Comparison of Classical and Operant Conditioning
Classical Conditioning
Operant Conditioning
The Response
Involuntary, automatic
“Voluntary,” operates on environment
Acquisition
Associating events; CS announces
UCS.
Associating response with a consequence (reinforcer or punisher).
Extinction
CR decreases when CS is repeatedly
presented alone.
Responding decreases when reinforcement stops.
Cognitive
processes
Subjects develop expectation that
CS signals the arrival of UCS
Subjects develop expectation that a
response will be reinforced or punished;
they also exhibit latent learning, without
reinforcement.
Biological
Natural predispositions constrain
predispositions stimuli and responses can easily be
associated.
Organisms best learn behavior similar to
their natural behaviors; unnatural behaviors instinctively drift back toward
natural ones.
Observational Learning
Observational Learning
learning by observing and imitating the
behavior of others
Modeling
process of observing and imitating
behavior
Prosocial Behavior
positive, constructive, helpful behavior
opposite of antisocial behavior
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