ch_8 powerpoint (learning)

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Myers’
PSYCHOLOGY
Chapter 8
Learning
Learning
Adaptability- we have a unique gift…
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
Learning = Experience
 Conditioning:
Classical- we learn to associate two things
together and anticipate what will happen next.
Operant- we learn to associate our behavior
with a consequence.
This leads to Associative Learning.
 Observational:
Watch others to learn new stuff…
This is what we call Observational Learning.
Association
Event 1
Event 2
Learning to
associate
two events
Sea snail associates splash with a tail shock
Seal learns to expect a snack for its showy antics
Classical /Pavlovian
Conditioning (Watson)
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
We learn to
associate a
response and
its
consequence
Response: Pushing
vending machine
button
Consequence:
Receiving a candy bar
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
Classical or Pavlovian
Conditioning
Ivan Pavlov
1849-1936
Russian physician/ neurophysiologist
Nobel Prize in 1904
studied digestive secretions
Pavlov’s Classic
Experiment
Before Conditioning
UCS (food
in mouth)
UCR
(salivation)
During Conditioning
Neutral
stimulus
(tone)
No
salivation
After Conditioning
UCS (food
in mouth)
Neutral
stimulus
(tone)
UCR
(salivation)
CS
(tone)
CR (salivation)
Classical or Pavlovian
Conditioning
Pavlov’s device
for recording
salivation
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 (CS, bell) is paired with a
stimulus (US, food) that evokes the reflex
(UR, dog slobbers)
neutral stimulus (CS, bell) eventually comes
to evoke the reflex (CR, dog slobbers)
Classical or Pavlovian
Conditioning
Unconditioned Stimulus (UCS, food))
effective stimulus that unconditionallyautomatically and naturally- triggers a
response
Unconditioned Response (UCR, slobber)
unlearned, naturally occurring automatic
response to the unconditioned stimulus
salivation when food is in the mouth
Classical or Pavlovian
Conditioning
Conditioned Stimulus (CS, bell)
previously neutral stimulus that, after
association with an unconditioned stimulus,
comes to trigger a conditioned response
Conditioned Response (CR, slobber)
learned response to a previously neutral
conditioned stimulus
Conditioning 5 Keys
Acquisition- ½ second
the initial stage of learning, during which a
response is established and gradually
strengthened
in classical conditioning, the phase in which a
stimulus comes to evoke a conditioned
response
in operant conditioning, the strengthening of
a reinforced response
Classical or Pavlovian
Conditioning p.318
UCS
(passionate
kiss)
CS
(onion
breath)
CS
(onion
breath)
UCR
(sexual
arousal)
UCS
(passionate
Kiss)
CR
(sexual
arousal)
UCR
(sexual
arousal)
Conditioning
Extinction (salivation diminishes)
diminishing of a CR
in classical conditioning, when a
UCS does not follow a CS
in operant conditioning, when a
response is no longer reinforced
CS and no UCS= Extinction
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 CR (weakened
response though)
Generalization
tendency for a stimuli similar to CS to
evoke similar responses, key here is it
needs to be similar… Kids taught to
fear moving cars, torture, music.
Generalization- when petting Dog
Drops of saliva
60
in 30 seconds
50
40
30
20
10
Hind
0
Pelvis
Shoulder
paw
Front
paw
Thigh
Trunk
Foreleg
Part of body stimulated
Classical or Pavlovian
Conditioning
Discrimination (5th Key)
in classical conditioning, the ability to
distinguish between a CS and other stimuli
that do not signal and UCS
in operant conditioning, responding
differently to stimuli that signal a behavior
will be reinforced or will not be reinforced
Classical or Pavlovian
Conditioning
Weakness of this type of Classical
Don’t consider thinking or cognitive
processes such as expectations, perception.
Don’t consider biological predisposition. All
creatures/ people are different and have
different learning capacities. For example,
the effect does not immediately have to
follow the cause. Ex. cancer patients
Applications: see p.324 for specifics.
Nausea Conditioning in
Cancer Patients
UCS
(drug)
UCR
(nausea)
CS
(waiting
room)
UCS
(drug)
UCR
(nausea)
CS
(waiting
room)
CR
(nausea)
Operant Conditioning:
Training for things we don’t naturally
do. Yes, please.
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 and behaviors followed by unfavorable
consequences become less 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
stimulus
behavior learned through classical
conditioning
Operant Conditioning
B.F. Skinner (1904-1990)
elaborated Thorndike’s Law of
Effect. Skinner’s box.
Behavioral technology.
developed behavioral technology,
cats and a fish reward.
Operant Chamber
Skinner Box
soundproof
chamber with a
bar or key that an
animal presses or
pecks to release a
food or water
reward
contains a device
to record
responses
Operant Conditioning
Reinforcer
any event that strengthens the behavior
it follows
Shaping
conditioning procedure in which
reinforcers guide behavior toward closer
approximations of a desired goal
Successive Approximations
reward behaviors that increasingly
resemble desired behavior
Principles of
Reinforcement
Primary Reinforcer
innately reinforcing stimulus
satisfies a biological need
Secondary Reinforcer
conditioned reinforcer
learned through association with
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)
reinforces a response only after a
specified number of responses
faster you respond the more rewards you
get
different ratios
very high rate of responding
like piecework pay
Schedules of
Reinforcement
Variable Ratio (VR)
reinforces a response after an
unpredictable number of responses
average ratios
like gambling, fishing
very hard to extinguish because of
unpredictability
Schedules of
Reinforcement
Fixed Interval (FI)
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)
reinforces a response at
unpredictable time intervals
produces slow steady responding
like pop quiz
Schedules of
Reinforcement
End day 2 notes
Number of
responses
1000
Fixed Ratio
Variable Ratio
Fixed Interval
750
Rapid responding
near time for
reinforcement
500
Variable Interval
250
Steady responding
0
10
20
30
40
50
Time (minutes)
60
70
80
Coaching philosophy…
Uncoachable kids become
unemployable adults.
Let your kid get used to
somebody being tough on
them!
That's life, get over it!
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
Cognition and Operant
Conditioning
Overjustification Effect
the effect of promising a reward for
doing what one already likes to do
the person may now see the reward,
rather than intrinsic interest, as the
motivation for performing the task
Operant vs Classical 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
predispositions
Natural predispositions
contain what stimuli and
responses can easily be
associated.
Organisms best learn behaviors
similar to their natural behaviors;
unnatural behaviors instinctively
drift back toward natural ones.
End day 3 notes
Observational Learning
Observational Learning
learning by observing and imitating others
Modeling
process of observing and imitating
behavior
Prosocial Behavior
positive, constructive, helpful behavior
opposite of antisocial behavior
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