Classical Conditioning

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Learning

Learning
 Lasting
change in an
organism’s
behavior due
to experience
Association
 We learn by association
 Our minds naturally connect events that
occur in sequence
 Aristotle 2000 years ago
 John Locke and David Hume 200 years ago
 Associative Learning
 learning that two events occur together
 two stimuli
 a response and its consequences
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 or Pavlovian
Conditioning
 We learn
to
associate
two
stimuli
Operant
Conditioning
 We learn to
associate a
response and
its
consequence
Classical Conditioning
 Classical Conditioning
Ivan Pavlov
 organism comes to associate two
stimuli
 a neutral stimulus that signals an
unconditioned stimulus begins to
produce a response that anticipates
and prepares for the unconditioned
Classical Conditioning
 Ivan Pavlov
 1849-1936
 Russian
physician/
neurophysiologist
 Nobel Prize in
1904
 studied digestive
secretions
Classical Conditioning
 Pavlov’s device
for recording
salivation
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 Conditioning
NEUTRAL STIMULUS
will
elicit
NO REACTION
UNCONDITIONED STIMULUS
will
elicit a
REFLEX ACTION
will
elicit a
REFLEX ACTION
will
elicit a
CONDITIONED
RESPONSE
UNCONDITIONED STIMULUS
NEUTRAL STIMULUS
CONDITIONEDSTIMULUS
STIMULUS
CONDITIONED
Classical Conditioning
 Unconditioned Stimulus (UCS)
 stimulus that unconditionally--automatically
and naturally--triggers a response In Pavlov’s
experiments the food was the UCS
 Unconditioned Response (UCR)
 unlearned, naturally occurring response to
the unconditioned stimulus
 salivation when food is in the mouth
 UCS-UCR connection involves no learning
Classical Conditioning
 Conditioned Stimulus (CS)
 originally irrelevant stimulus that, after
association with an unconditioned stimulus,
comes to trigger a conditioned response the
tone produced
 Conditioned Response (CR)
 learned response to a previously neutral
conditioned stimulus Salivation when bell
rings.
Classical Conditioning
 Acquisition
 the initial stage in classical
conditioning
 the phase associating a neutral
stimulus with an unconditioned
stimulus so that the neutral stimulus
comes to elicit a conditioned
response
 in operant conditioning, the
strengthening of a reinforced
response
Classical Conditioning
UCS
(passionate
kiss)
CS
(onion
breath)
CS
(onion
breath)
UCR
(sexual
arousal)
UCS
(passionate
Kiss)
CR
(sexual
arousal)
UCR
(sexual
arousal)
Classical Conditioning
 Extinction
 diminishing of a CR
 in classical conditioning,
when the presentation
of CS without the UCS
 in operant conditioning,
when a response is no
longer reinforced
Classical
Conditioning
Strength
of CR
Acquisition
Acquisition
(CS+UCS)
CS+UCS
Extinction
Extinction
(CS alone)
CS alone
Spontaneous
recovery of
CR
Spontaneous
Extinction
recovery
(CS
alone)
Pause
Variations Within
Classical Conditioning
Extinction
If a stimulus is never reinforced, then the response will go away.
Spontaneous Recovery
After extinction, a response will suddenly reappear.
Learn not to respond to CS.
Generalization
A response can be generalized to other like stimuli. All spiders are scary.
Generalization is a behavior
that spreads from one situation
to a similar one. (A baby will
call Daddy “Dada.” When the
baby sees any man, the baby
calls out “Dada.”)
Discrimination is the reverse of generalization.
Some stimuli have pleasant consequences and
some do not. (A baby gradually learns that
only one person responds with a smile when
called “Dada.”)
Cognitive Processes
Conditioning occurs best when the
CS and UCS have just the sort of
relationship that would lead a
scientist to conclude that the CS
causes the UCS. — even in
classical conditioning, it is not only
the simple stimulus-response
association but also the thought
that counts.
 Conditioning in advertising
 John
Biological
Predispositions
Garcia
Conditioned taste aversions
 Not
all neutral stimuli can become
conditioned stimuli.
 Internal stimuli—associate better with taste
 External stimuli—associate better with pain
 Biological preparedness
Nausea Conditioning in 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 agreedupon consensus
today
 recommended
study of behavior
without reference
to unobservable
mental processes
 not universally
accepted by all
Watson took a a baby named Albert and conditioned him to be
afraid of white furry objects using Pavlov’s techniques.
Watson & Raynor with Little Albert
Conditional Training:
Albert and Peter
Conditioned fear
experiments such as
Albert’s experience
would never occur
today because of the
existing ethical
standards.
Mary Cover Jones
Mary Cover Jones used an
early form of desensitization
to prove that fears (phobias)
could be unlearned.
Peter, a young boy, had an extreme fear of
rabbits. Jones gave Peter his favorite food
while slowly bringing the rabbit closer and
closer. Eventually Peter no longer panicked
around rabbits.
1.
By learning to associate a squirt of water with electric shock, sea snails demonstrate the process of:
a.
habituation
b.
spontaneous recovery
c.
classical conditioning
d.
observational learning
e.
operant conditioning
2.
John B. Watson considered himself to be a(n):
a.
Physiological psychologist
b.
Cognitive psychologist
c.
Behaviorist
d.
Psychoanalyst
e.
Operant conditioner
3.
In Pavlov’s experiments, the dog’s salivation triggered by the taste of food was a(n):
a.
Conditioned response.
b.
Unconditioned stimulus.
c.
Unconditioned response.
d.
Conditioned stimulus.
4.
In Pavlov’s experiments, the dog’s salivation triggered by the sound of the tone was a(n):
a.
Conditioned response.
b.
Unconditioned stimulus.
c.
Unconditioned response.
d.
Conditioned stimulus.
5.
If a bell causes a dog to salivate because it has regularly been associated with the presentation
of food, the bell is called a(n):
a.
Unconditioned stimulus.
b.
Conditioned stimulus.
c.
Primary reinforcer.
d.
Immediate reinforcer.
6.
The initial stage of classical conditioning during which a response to a neutral stimulus is established and
gradually strengthened is called:
a.
Acquisition.
b.
Association.
c.
Observational learning.
d.
Shaping.
7. When a CS is not followed by a UCS, the subsequent fading of a CR is called:
a.
Discrimination.
b.
Generalization.
c.
Delayed reinforcement.
d.
Extinction.
8. The reappearance, after a time lapse, of an extinguished CR is called:
a.
Generalization.
b.
Spontaneous recovery.
c.
Secondary reinforcement.
d.
Latent learning.
e.
Shaping.
9. The tendency for a CR to be evoked by stimuli similar to the CS is called:
a.
Generalization.
b.
Secondary reinforcement.
c.
Latent learning.
d.
Spontaneous recovery.
e.
Shaping.
10. The ability to distinguish between a conditioned stimulus and similar stimuli that do not signal an unconditioned
stimulus is called:
a.
Shaping.
b.
Acquisition.
c.
Discrimination.
d.
Generalization.
e.
Latent learning.
11. Little Albert developed a fear of rats after a white rat was presented with a loud noise. In this case, the loud
noise was the:
a.
Unconditioned stimulus.
b.
Conditioned stimulus.
c.
Secondary reinforcer.
d.
Delayed reinforcer.
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, and behaviors
followed by unfavorable
consequences become less likely
Operant
Conditioning
 Operant Behavior
 operates (acts) on
environment
 produces consequences
 Respondent Behavior
 occurs as an automatic
response to stimulus
 behavior learned through
classical conditioning
Early Operant
Conditioning
E. L. Thorndike (1898)
Puzzle boxes and cats
First Trial
in Box
Situation:
stimuli
inside of
puzzle box
Scratch at bars
Push at ceiling
Dig at floor
Howl
Etc.
After Many
Trials in Box
Situation:
stimuli
inside of
puzzle box
Scratch at bars
Push at ceiling
Dig at floor
Howl
Etc.
Etc.
Etc.
Press lever
Press lever
Edward L. Thorndike ( 1874–1949)
Operant
Conditioning
 B.F. Skinner
(1904-1990)
 elaborated
Thorndike’s Law
of Effect
 developed
behavioral
technology
B. F. Skinner (1904–1990)
Operant Chamber
 Skinner Box
 chamber with a
bar or key that
an animal
manipulates to
obtain a food or
water reinforcer
 contains devices
to record
responses
Operant Conditioning
In shaping, successively closer
versions of a desired response are
reinforced (as in learning to play
tennis).
In chaining, each part of a sequence is reinforced; the
different parts are put together into a whole (as in
learning the steps to a dance).
Disco Dog Video
41
Operant
Conditioning
 Positive Reinforcement
 any event that strengthens the
behavior it follows
 Negative Reinforcement
 The removal of a punishment or an
aversive stimulus
 It STRENGTHENS behavior
Operant Conditioning
Operant Conditioning Processes
Primary Reinforcement is unlearned and usually
necessary for survival. Food is the best example
of a primary reinforcer.
Secondary Reinforcement is anything that comes to
represent a primary reinforcer such as praise from a
friend or a gold star on a homework assignment.
Also called conditioned reinforcer.
Schedules of
Reinforcement
 Immediate Reinforcers
 To our detriment, small but immediate
reinforcements are sometimes more alluring than
big, but delayed reinforcements
 Continuous Reinforcement
 reinforcing the desired response each time it occurs
Learning occurs rapidly, but rapid extinction. This is
the best way master behavior.
 Partial (Intermittent) Reinforcement
 reinforcing a response only part of the time
 results in slower acquisition
 greater resistance to extinction Hope springs eternal
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 paid after producing
30 lamps
Schedules of
Reinforcement
 Variable Ratio (VR)
 reinforces a response after an
unpredictable number of responses
 average ratios
 like gambling (slots), fishing winning
the derby
 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. Mail comes a noon
Schedules of
Reinforcement
 Variable Interval (VI)
 reinforces a response at
unpredictable time intervals
 produces slow steady responding
 like pop quiz
Schedules of
Reinforcement
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
Punishment
 Punishment
 aversive event that
decreases the behavior
that it follows
 powerful controller of
unwanted behavior
Punishment
Problems with
Punishment
Does not teach or promote
alternative, acceptable
behavior
May produce undesirable
results such as hostility,
passivity, fear
Likely to be temporary
May model aggression
Updating Skinner’s Understanding
Skinner’s emphasis on
external control of behavior
made him an influential, but
controversial figure. Many
psychologists criticized Skinner
for underestimating the
importance of cognitive and
biological constraints.
Cognitive Approach
This approach emphasizes abstract and subtle learning
that could not be achieved through conditioning or social
learning alone.
Some learning is not intentional, but occurs almost
accidentally—a situation called latent learning. Learning
that occurs, but is not apparent until there is an
incentive to demonstrate it
Expectancies are beliefs about our ability to perform an
action and to get the desired reward. Expectancies
affect learning.
Latent Learning
Cognitive Maps
Cognitive Map (E.C. Tolman)
A 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
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
Cognition and
Operant Conditioning
 Intrinsic Motivation
 Desire to perform a behavior
for its own sake and to be
effective
 Extrinsic Motivation
 Desire to perform a behavior
due to promised rewards or
threats of punishments
Applications of
Operant Conditioning
 School
 Work
 Home
1.
Ever since his mother began to give Julio gold stars for keeping his bed dry all night, Julio discontinued his habit
of bedwetting. His change in behavior best illustrates the value of:
a.
Primary reinforcement.
b.
Classical conditioning.
c.
Spontaneous recovery.
d.
Operant conditioning.
e.
Latent learning.
2.
B.F. Skinner’s work elaborate what E.L. Thorndike had called:
a.
shaping
b.
behaviorism
c.
observational learning
d.
the law of effect
e.
latent learning
3.
Dr. Kevorkian places a rat in a small, glass-enclosed chamber where it learns to press a bar to obtain a food
pellet. Obviously, Dr.Kevorkian is using a _________________ to study learning.
a.
Pavlovian maze
b.
Bandura compartment
c.
Skinner box
d.
Garcia operant chamber
4.
The process of reinforcing successively closer approximations to a desired behavior is called:
a.
Shaping.
b.
Partial reinforcement.
c.
Generalization.
d.
Secondary reinforcement.
e.
Modeling.
5.
An event that increases the frequency of the behavior that it follows is a(n):
a.
Conditioned stimulus.
b.
Respondent.
c.
Unconditioned stimulus.
d.
Reinforcer.
e.
Operant.
6.
Because Bertha would always pick up her newborn daughter when she began to cry, her daughter is now a real
crybaby. In this case, picking up the infant served as a(n) ____________for crying.
a.
Negative reinforcer
b.
Conditioned stimulus
c.
Positive reinforcer
d.
Unconditioned stimulus
7.
Escape
a.
b.
c.
d.
e.
8.
Innately satisfying stimuli that satisfy biological needs are called ________________ reinforcers.
a.
Fixed
b.
Primary
c.
Positive
d.
Continuous
9.
A stimulus that acquires reinforcing power by association with another reinforcer is called a _________________
reinforcer.
a.
Negative
b.
Primary
c.
Partial
d.
Secondary
e.
Positive
from an aversive stimulus is a _________________ reinforcer.
Positive
Secondary
Negative
Partial
Delayed
10. Resistance to extinction is most strongly encouraged by _______________ reinforcement.
a.
Delayed
b.
Negative
c.
Secondary
d.
Partial
11. A fixed-ratio schedule of reinforcement is one in which a response is reinforced only after a(n):
a.
Specified time period has elapsed.
b.
Unpredictable time period has elapsed.
c.
Specified number of responses have been made.
d.
Unpredictable number of responses have been made.
12. Gamblers who insert coins in a slot machine are reinforced on a __________________ schedule.
a.
Fixed-interval
b.
Variable-interval
c.
Fixed-ratio
d.
Variable-ration
13. A fixed-interval schedule of reinforcement is one in which a response is reinforced only after a(n):
a.
Specified time period has elapsed.
b.
Unpredictable time period has elapsed.
c.
Specified number of responses have been made.
d.
Unpredictable number of responses have been made.
14. On the first day of class Mrs. Quigley tells her history students that pop quizzes will be given at unpredictable
times throughout the semester. Clearly, studying for Mrs. Quigley’s surprise quizzes will be reinforced on a
____________________- schedule.
a.
Fixed-interval
b.
Fixed-ratio
c.
Variable-interval
d.
Variable-ratio
15. B.F. Skinner’s critics have claimed that he neglected the importance of the individual’s:
a.
personal freedom
b.
early childhood experiences
c.
pleasure-seeking tendencies
d.
cultural background
Operant vs.
Classical Conditioning
Observational Learning
 Observational Learning (Albert
Bandura)
 learning by observing and imitating
others
 Modeling
 process of observing and imitating
a specific behavior
 Prosocial Behavior
 positive, constructive, helpful
behavior
 opposite of antisocial behavior
This series of photographs shows children
observing and modeling aggressive behavior.
Albert Bandura’s Bobo Doll Experiment
Observational Learning
 Mirror Neurons
 frontal lobe neurons that fire
when performing certain
actions or when observing
another doing so
 may enable imitation,
language learning, and
empathy
Famous last words???
Do what I say, not what I do—
This will teach you to hit your
brother—
Why do you do that, you know
you get in trouble for it—
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