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Learning
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Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Definition of Learning
Learning is “any relatively permanent
change in behavior brought about through
experience.”
– Conditioning:
• The acquisition of specific patterns of behavior in
the presence of well-defined stimuli.
Two Types of Conditioning
• Classical (C.C.):
– a response naturally elicited by one stimulus
comes to be elicited by a different, formerly
neutral stimulus
• Operant (O.C.):
– behaviors are emitted (in the presence of
specific stimuli) to earn rewards or avoid
punishments
Learning
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Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Pavlov
It all starts with a REFLEX
It all starts with a REFLEX
Automatic
It all starts with a REFLEX
Unconscious
It all starts with a REFLEX
Involuntary
It all starts with a REFLEX
Inborn
REFLEX
Causes
Stimulus
Response
REFLEX
Leads to
Stimulus
Response
REFLEX
Elicits
Stimulus
Response
REFLEX
Causes
Stimulus
Puff of air
to the eye
Response
Blink
REFLEX
Causes
Stimulus
Light in
the eye
Response
Pupillary
Constriction
REFLEX
Causes
Stimulus
Pain
Response
Withdrawal
REFLEX
Causes
Stimulus
Meat
Powder in
mouth
Response
Salivation
REFLEX
Causes
Stimulus
Electric
Shock
Response
Fear
REFLEX
Unconditioned Stimulus
Unconditioned Response
REFLEX
UCS
UCR
Click
??
Some stimuli do nothing
Click
Some stimuli do nothing
Footsteps
Some stimuli do nothing
Metronome
Some stimuli do nothing
Rabbit
Some stimuli do nothing
Hiss
Some stimuli do nothing
Neutral Stimulus
Some stimuli do nothing
NS
Learning involves repeated pairing
Learning involves repeated pairing
UCS
UCR
Learning involves repeated pairing
NS
+
UCS
UCR
After repeated pairing
NS
+
CS
UCS
UCR
CR
After repeated pairing
CS
CR
After repeated pairing
CS
CR
Learning involves repeated pairing
NS
Hiss
+
UCS
Puff
UCR
Blink
After repeated pairing
NS
Hiss
+
CS
UCS
Hiss
Puff
CR
UCR
Blink
After repeated pairing
CS
Hiss
CR
Blink
After repeated pairing
CS
Hiss
CR
Blink
REFLEX
Causes
Some stimuli do nothing
Learning involves repeated pairing
Learning involves repeated pairing
Learning involves repeated pairing
After repeated pairing
After repeated pairing
After repeated pairing
After repeated pairing
the organism has formed an
association between the once
neutral stimulus and the
unconditioned stimulus.
An example
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It all begins with a REFLEX
Learning
Classical Conditioning
Reflexes
A relatively simple, automatic, stimulus-response
sequence that is mediated by the CNS
• Unconditioned stimulus
(UCS).
– Elicits a response in the
absence of learning.
• Unconditioned response
(UCR).
– The reflexive response to a
stimulus in the absence of
learning.
UCS  UCR
• No learning here. Organism
is born with this reflex
Operant Conditioning
Ecological Learning
Observational Learning
New Reflexes from Old
Learning
Classical Conditioning
• A neutral stimulus is then regularly
paired with an unconditioned
stimulus.
Operant Conditioning
Ecological Learning
Observational Learning
New Reflexes from Old
•
Conditioned stimulus (CS).
–
•
An initially neutral stimulus that
comes to elicit a conditioned
response after being paired with
an unconditioned stimulus.
Conditioned response (CR).
–
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–
A response that is elicited by the
conditioned stimulus.
Occurs after the CS is associated
with the US.
Identical to the US
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Classical Conditioning Diagram
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Reflex
Observational Learning
NS + UCS  UCR
(BELL)
(PUFF)
(BLINK)
CS  CR
(BELL)
(BLINK)
Classical Conditioning
Learning
Classical Conditioning
Operant Conditioning
Prior to
conditioning
UCS
(food powder in mouth)
UCR
(salivation)
Neutral stimulus
(tone)
Neutral stimulus
CS (tone)
CR
(salivation)
Conditioning
UCS
(food powder)
After conditioning
CS
(tone)
CR
(salivation)
Ecological Learning
Observational Learning
In Watson’s Little Albert study, the
conditioned response was
1. Salivation
2. Nausea
3. Fear
0%
1
0%
2
0%
3
10
In Pavlov’s original experiments, the
neutral stimulus was the
1. Sound of the
footsteps
2. Taste of the
meat powder
3. Sight of the
white lab coat
0%
1
0%
2
0%
3
10
In Pavlov’s original experiments, the
conditioned stimulus was the
1. Sound of the
footsteps
2. Taste of the
meat powder
3. Sight of the
white lab coat
0%
1
0%
2
0%
3
10
When you first went to the dentist as a child, you heard the highpitched whine of the drill, and had no reaction. After you’ve had your
first filling, the drill causes a nervous reaction - cold hands, increased
heart rate and blood-pressure, etc. The drill became the
1. Conditioned
Stimulus
2. Unconditioned
stimulus
3. Conditioned
Response
0%
1
0%
2
0%
3
10
From the last question, the
anxiety is the
1. Neutral Stimulus
2. Conditioned
Stimulus
3. Conditioned
Response
0%
1
0%
2
0%
3
10
The neutral stimulus was the
1. Sight of the
dentist
2. Sound of the drill
3. Anxiety
0%
1
0%
2
0%
3
10
Although you’ve never been afraid of flying, the last time you flew
the plane went into a nosedive for nearly a minute. Now when you
fly, you get extremely nervous. In this example, flying is the
1. Conditioned
response
2. Conditioned
stimulus
3. Unconditioned
response
0%
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0%
2
0%
3
10
From the previous example, what is
the unconditioned response?
1. The sight of the
airplane
2. Salivating
3. Fear
0%
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Basic Rules of Conditioning
Learning
Classical Conditioning
• The more association trials, the
better the conditioning
• CS and US must be closely linked
in time
• Physically intense stimuli are
conditioned more easily
• Some responses are more easily
conditioned than others
Operant Conditioning
Ecological Learning
Observational Learning
Contingency
Learning
Classical Conditioning
Contingency
Operant Conditioning
Ecological Learning
Observational Learning
Classical Conditioning
Learning
Classical Conditioning
Extinction –
Operant Conditioning
Ecological Learning
Observational Learning
Weakening of a conditioned
association in the absence of an
unconditioned stimulus or
reinforcer
Spontaneous recovery –
Reappearance of an extinguished
conditioned response after a time
delay
Acquisition, Extinction, and
Spontaneous Recovery
Learning
Classical Conditioning
Spontaneous Recovery
Operant Conditioning
Ecological Learning
Observational Learning
Classical Conditioning
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
• Higher order conditioning
• Stimulus generalization
• Discrimination learning
Observational Learning
Higher-Order Conditioning
Learning
Classical Conditioning
• A neutral stimulus can become a conditioned
stimulus (CS) by being paired with an existing
conditioned stimulus (CS).
Higher-Order Cond.
Operant Conditioning
Ecological Learning
Observational Learning
Stimulus Generalization
Learning
Classical Conditioning
• Occurs when a new stimulus that resembles the
conditioned stimulus, elicits the conditioned
response.
Stimulus Generalization
Operant Conditioning
Ecological Learning
Observational Learning
Stimulus Discrimination
Learning
Classical Conditioning
• The tendency to respond differently
to two or more similar stimuli.
• In classical conditioning, it occurs
when a stimulus similar to the
condition stimulus (CS) fails to
evoke a conditioned response (CR).
Discrimination
Operant Conditioning
Ecological Learning
Observational Learning
Real-Life Examples
Learning
Classical Conditioning
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Drug overdoses
Smoking: environmental cues
Systematic desensitization
Advertising: sex appeal
Taste aversion
Conditioning and the immune system
Examples
Operant Conditioning
Ecological Learning
Observational Learning
Abnormal Behavior and CC
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
NS + UCS  UCR
(Dog)
(Pain from Bite)
CS  CR
(Dog)
(Fear)
(Fear)
Observational Learning
Learning
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Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Operant Conditioning
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
The consequences that follow a
behavior make that behavior more
or less likely to occur in the future.
•Make behavior more likely – Reinforcement
•Make behavior less likely - Punishment
Operant Conditioning
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
•Operant behaviors are different from the
responses involved in classical
conditioning
–They are voluntarily emitted
–Those involved in classical conditioning
are elicited by stimuli.
Observational Learning
ALL reinforcers
increase the
likelihood that a
response will
become more
frequent
Reinforcement
Learning
Classical Conditioning
• What is a reinforcer?
– Definition: a reinforcer is any stimulus
which, when delivered to a subject,
increases the probability that a subject
will emit the most recent response.
• Primary reinforcers, e.g., food
• Secondary reinforcers, e.g., praise
– One can only know if a stimulus is a
reinforcer based on the increased
probability of occurrence of a subject’s
behavior
Operant Conditioning
Ecological Learning
Observational Learning
Reinforcement
Learning
Classical Conditioning
Positive reinforcers –
Operant Conditioning
Ecological Learning
Observational Learning
Stimulus, contingent on a particular behavior,
that increases the probability of that response
happening again
Negative reinforcers –
Removal of an unpleasant stimulus, contingent
on a particular behavior, that increases the
probability of that response happening again
Examples of Consequences
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Positive
Negative
Behavior
Reinforcement
Give food for
correct response
Remove shock for
correct response
Increases
Punishment
Give shock for
incorrect response
Remove food for
incorrect reponse
Decreases
Reinforcement
Learning
Primary reinforcers –
Reinforcers, such as food and sex, that have an
innate basis because of their biological value to
an organism
Secondary reinforcers –
Stimuli, such as money or tokens, that acquire
their reinforcing power by their learned
association with primary reinforcers
(also called conditioned reinforcers)
Classical Conditioning
Classical Conditioning
Operant Conditioning
Ecological
Operant
Conditioning
Learning
Observational Learning
Ecological Learning
Observational Learning
Schedules of Reinforcement
Learning
Classical Conditioning
Operant Conditioning
Continuous reinforcement –
Reinforcement schedule in which all correct
responses are reinforced
Partial reinforcement –
Reinforcement schedule in which some, but not
all, correct responses are reinforced
(also called intermittent reinforcement)
Ecological Learning
Observational Learning
Schedules of Reinforcement
Learning
Classical Conditioning
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)
Operant Conditioning
Ecological Learning
Observational Learning
Schedules of Reinforcement
Learning
Classical Conditioning
Operant Conditioning
Fixed Ratio (FR) Rewards appear after
a certain set number
of responses
Variable Ratio
(VR)
e.g. factory workers
getting paid after
Fixed Interval
every
10
cases
of
(FI)
product are
Variable Interval completed
(VI)
Ecological Learning
Observational Learning
Schedules of Reinforcement
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Fixed Ratio (FR) Rewards appear after
a certain number of
responses,
but
that
Variable Ratio
number varies from
(VR)
reinforcer to
reinforcer
Fixed Interval
(FI)
e.g. slot machine
Variable Interval pay-offs
(VI)
Observational Learning
Schedules of Reinforcement
Learning
Classical Conditioning
Rewards appear after
Fixed Ratio (FR) a certain fixed
amount of time,
regardless of number
Variable Ratio
of responses, as long
(VR)
as the response
Fixed Interval
occurs during the
(FI)
interval.
Variable Interval
(VI)
e.g. weekly or
monthly paychecks
Operant Conditioning
Ecological Learning
Observational Learning
Schedules of Reinforcement
Learning
Classical Conditioning
Rewards appear after
Fixed Ratio (FR) a certain amount of
time, but that amount
varies
from
trial
to
Variable Ratio
trial, as long as the
(VR)
response occurs
during the interval.
Fixed Interval
(FI)
e.g. random visits
Variable Interval from the boss who
delivers praise
(VI)
Operant Conditioning
Ecological Learning
Observational Learning
Schedules of Reinforcement
Learning
• Simple
reinforcement
schedules produce
characteristic
response patterns
• Steeper lines mean
higher response
rates
• Ratio schedules
produce higher
response rates than
interval schedules
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Partial Reinforcement
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
A rat is given a food pellet every
time it presses a bar 7 times.
1.
2.
3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
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An instructor gives an exam
every Friday afternoon.
1.
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3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
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Another instructor gives pop
quizzes at random times.
1.
2.
3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
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A migrant worker gets $3.00 for every
ten baskets of cherries he picks.
1.
2.
3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
0%
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Every time Mary puts her Charlie Card
into the turnstile, she is allowed on the T
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2.
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4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
0%
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A salesman makes calls on 14
potential customers per day.
1.
2.
3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
0%
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You call your best friend from high
school, and keep getting a busy signal.
1.
2.
3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
0%
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John stands at the T stop and peeks around
the corner to see if the train is coming.
1.
2.
3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
0%
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4
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Coming to work on Friday results in a
paycheck for work completed during the week
1.
2.
3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
0%
1
0%
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4
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A friend of yours wants you to study more, so she comes to
your room with chocolate cookies every so often. If she
finds you studying then you get a cookie.
1.
2.
3.
4.
Fixed Ratio
Variable Ratio
Fixed Interval
Variable Interval
0%
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4
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Persistence of
Avoidance Learning
Learning
Classical Conditioning
• Negatively reinforced responses
show slower extinction than
positively reinforced responses
Operant Conditioning
Ecological Learning
Observational Learning
Problems with Punishment
Learning
Classical Conditioning
• Too uninformative – only tells learner what NOT to do, not
what TO do.
• Tends to work well only when punisher present
(unlike reinforcement) - this often accidentally leads to a partial schedule
of reinforcement.
• Tends to cause fear in learner - (who stops ALL behavior)
– classically conditioned response
• Constant effectiveness requires escalation
• Often the easiest and quickest consequence, but
rarely the most effective at changing behavior.
Operant Conditioning
Ecological Learning
Observational Learning
Alternatives to Punishment
Learning
Classical Conditioning
Operant Conditioning
• Extinction
• Reinforcing preferred
activities
–Premack principle
• Shaping
Ecological Learning
Observational Learning
Shaping
Learning
Classical Conditioning
• To teach complex behaviors, may
need to reinforce successive
approximations of a desired
response.
• For example, training animals,
getting children to make their
beds.
Operant Conditioning
Ecological Learning
Observational Learning
Shaping
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
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The Death of Behaviorism
Tolman’s Latent Learning
Learning
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Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Limitations to Pavlov’s and
Skinner’s Theories of Learning
Learning
Classical Conditioning
• Preparedness
– some associations are learned more
easily than others (e.g. associating taste
with nausea is easier than associating
noise with nausea).
– One-trial learning
– Spider and snake phobias are easier to
condition than flower and rock phobias.
– Species specific behaviors sometimes
hard to modify
Operant Conditioning
Ecological Learning
Observational Learning
Conditioned Taste Aversions
Learning
Classical Conditioning
Operant Conditioning
Biological tendency in which an
organism learns to avoid food
with a certain taste after a single
experience, if eating it is
followed by illness
Ecological Learning
Observational Learning
Application of psychology:
Learning the wrong things
Learning
Classical Conditioning
• What is superstitious behavior?
– non-contingent reinforcement
– examples of superstitions
• Learned helplessness
– the cessation of all behavior as a result of
intense punishment
– dog’s behavior in electrified cage
– wife’s behavior in an abusive marriage
Operant Conditioning
Ecological Learning
Observational Learning
Learning
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Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
QuickTime™ and a
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are needed to see this picture.
Social Learning
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
• Social cognitive theories emphasize how behavior
is learned and maintained:
– through observation and imitation of others,
– positive consequences,
– cognitive processing such as plans, expectations, and
beliefs.
• Observational learning involves learning new
responses by observing the behavior of another
rather than through direct experience.
Bandura, Ross, and Ross (1963).
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
• Nursery school children watched a film of
2 men (Johnny and Rocky) playing with
toys.
• Johnny refuses to share and Rocky hits
him, ending up with all the toys.
• Children who watched the video were
significantly more violent than children in
a control group.
Observational Learning
• Bandura’s Bobo doll study
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning
Bandura’s Results
Learning
Classical Conditioning
Operant Conditioning
Ecological Learning
Observational Learning