Classical Conditioning

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AP Psychology
Chapter 8
1
A Thought


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Unlike some animals we are not born
with a genetic blueprint for life.
Nature's most important gift to us may be
our adaptability – our capacity to learn
new behaviors that enable us to cope
with changing circumstances.
Learning- a relatively permanent change
in an organism's behavior due to
experience
2
How do we learn

What are some ways that you learn?
 Seeing
 Doing
 Associating
 Which one?
3
Association
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Animals can learn simple associations
Complex animals learn more response –
outcome associations.
Associate learning- learning that certain
events occur together. The events may be
stimuli (as in classical conditioning) or a
response and its consequences (as in
operant conditioning.
4
Conditioning


Conditioning is the process of learning
associations.
Classical Conditioning


A type of learning in which an organism comes
to associate stimuli. A neutral stimulus that
signal an unconditional stimulus (US) begins to
produce a response that anticipates and
prepares for the unconditional stimulus. Also
know as Pavlovian or respondent conditioning.
Good example is Pavlov
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Operant Conditioning



We learn to associate a response (our
behavior) and its consequences and thus to
repeat acts followed by good results.
Conditioning is not the only form of learning.
Through observational learning we learn
from others experiences and examples.
By conditioning and by observation we
humans learn and adapt to our
environments.
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Classical Condtioning


Ivan Pavlov
A type of learning in which an organism
comes to associate stimuli. A neutral
stimulus that signal an unconditional
stimulus (US) begins to produce a response
that anticipates and prepares for the
unconditional stimulus. Also know as
Pavlovian or respondent conditioning.
7
Classical Conditioning

Classical conditioning would lead us into the
area of behaviorism and John Watson.
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Ivan Pavlov


US – unconditioned
stimulus. Naturally
and automatically triggers a response
UR- unconditioned
response -the
unlearned ,naturally
occurring response
to the unconditioned
stimulus.


CR- conditioned
response- the
learned response to
a previously neutral
stimulus.
CS- conditioned
stimulus- the
irrelevant stimulus
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A thought to ponder
Conditioned = learned
unconditioned = unlearned
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Cause and effects of classical
conditioning
1)Acquisition
2)Extinction
3)Spontaneous
4)Recovery
5)Generalization
6)Discrimination
11
Acquisition


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The initial stage in classical conditioning: the
phase associating a neutral stimulus with an
unconditional stimulus so that the neutral
stimulus comes to elicit a conditioned
response. In operant conditioning, the
strengthening of a reinforced response.
Extinction and Spontaneous Recovery
Extinction When the US (food) does not follow
the CS (tone), CR (salivation) begins to decrease
and eventually causes extinction.
12
Spontaneous Recovery
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
The reappearance after a pause, of an
extinguished conditioned response.
After a rest period, an extinguished CR (salivation)
spontaneously recovers, but if the CS (tone) persists alone,
the CR becomes extinct again.
13
Generalization


The tendency, once a response has been
conditioned, for a stimuli to elicit similar
response.
Tendency to respond to stimuli similar to the CS is
called generalization. Pavlov conditioned the dog’s
salivation (CR) by using miniature vibrators (CS)
on the thigh. When he subsequently stimulated
other parts of the dog’s body, salivation dropped.
14
Discrimination
Discrimination is the learned
ability to distinguish between a
conditioned stimulus and other
stimuli that do not signal an
unconditioned stimulus.
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15
Extending Pavlov’s Understanding
Pavlov and Watson considered
consciousness, or mind, unfit for the
scientific study of psychology.
However, they underestimated the
importance of cognitive processes
and biological constraints
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Cognitive Process
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Early behaviorists believed that learned behaviors
of various animals could be reduced to mindless
mechanisms
However, later behaviorists suggested that animals
learn the predictability of a stimulus, meaning they
learn expectancy or awareness of a stimulus
(Rescorla, 1988).
17
Biological Predispositions
Pavlov and Watson believed that
laws of learning were similar for all
animals. Therefore, a pigeon and a
person do not differ in their
learning.
 However, behaviorists later
suggested that learning is
constrained by an animal’s biology.

18
Biological Predispositions

John Garcia showed that the duration between the CS and
the US may be long (hours), but yet result in conditioning. A
biologically adaptive CS (taste) led to conditioning and not
to others (light or sound).
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Thank you Pavlov
Pavlov’s greatest contribution to
psychology is isolating elementary
behaviors from more complex ones
through objective scientific
procedures.

20
Applications of Classical
Conditioning
John B. Watson used classical
conditioning procedures to develop
advertising campaigns for a number
of organizations, including
Maxwell House, making the “coffee
break” an American custom.

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Why classical conditioning


Alcoholics may be conditioned
(aversively) by reversing their
positive-associations with alcohol.
Through classical conditioning, a
drug (plus its taste) that affects the
immune response may cause the
taste of the drug to invoke the
immune response.
22
Operant & Classical Conditioning

1. Classical conditioning forms associations
between stimuli (CS and US). Operant
conditioning, on the other hand, forms an
association between behaviors and the resulting
events.
23
Operant and classical
conditioning

Classical
conditioning involves
respondent behavior that occurs as
an automatic response to a certain
stimulus. Operant conditioning
involves operant behavior, a
behavior that operates on the
environment, producing rewarding
or punishing stimuli.
24
Skinner's Experiments
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
Edward Thorndike – behaviors followed by
favorable consequences become more likely,
and that behavior followed by unfavorable
consequences become less likely.
Skinner’s experiments extend Thorndike’s thinking,
especially his law of effect. This law states that
rewarded behavior is likely to occur again.
25
Operant Chamber


AKA the Skinner Box
It contains a bar that can be manipulated to
obtain a water or food reinforcer.
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Shaping

Shaping is the operant conditioning
procedure in which reinforcers guide
behavior towards the desired target
behavior through successive
approximations
 Rewards
 Treats
 Kind words
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Reinforcer
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 Primary Reinforcer: An innately reinforcing
stimulus like food or drink.
 Conditioned Reinforcer: A learned reinforcer that
gets its reinforcing power through association with
the primary reinforcer.
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Immediate & Delayed Reinforcers
1.
2.
Immediate Reinforcer: A reinforcer that occurs
instantly after a behavior. A rat gets a food pellet
for a bar press.
Delayed Reinforcer: A reinforcer that is delayed in
time for a certain behavior. A paycheck that comes
at the end of a week.
We may be inclined to engage in small immediate
reinforcers (watching TV) rather than large delayed
reinforcers (getting an A in a course) which require
consistent study.
29
Reinforcement Schedules
1.
2.
Continuous Reinforcement: Reinforces the
desired response each time it occurs.
Partial Reinforcement: Reinforces a response only
part of the time. Though this results in slower
acquisition in the beginning, it shows greater
resistance to extinction later on.
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Ratio Schedule

Fixed –ratio schedule In operant
conditioning, a reinforcement schedule that
reinforces only after a specified number of
responses.
Variable-interval schedule: Reinforces a
response at unpredictable time intervals,
which produces slow, steady responses. (e.g.,
pop quiz.)
31
Punishment
Punishment is the opposite of reinforcement. A punisher
is a consequence that decreases the frequency of a
preceding behavior.
1.
2.
3.
4.
5.
6.
Although there may be some justification for occasional
punishment (Larzelaere & Baumrind, 2002), it usually
leads to negative effects.
Results in unwanted fears.
Conveys no information to the organism.
Justifies pain to others.
Causes unwanted behaviors to reappear in its absence.
Causes aggression towards the agent.
Causes one unwanted behavior to appear in place of
another.
32
Punishment
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Punished behavior is not forgotten it is
suppressed.
Physical punishment may increase
aggressiveness by demonstrating that
aggression is a way to cope with problems
Can create fear
Punishment tells you what not to do
Reinforcement tells you to do.
33
Extending Skinner’s Understanding
Skinner believed in inner thought processes and
biological underpinnings, but many psychologists
criticize him for discounting them.
34
Cognition & Operant Conditioning
Evidence of cognitive processes during operant
learning comes from rats during a maze exploration in
which they navigate the maze without an obvious
reward. Rats seem to develop cognitive maps, or
mental representations, of the layout of the maze
(environment).
35
Latent Learning-learning that occurs
but is not apparent until there is an
incentive to demonstrate it.
Such cognitive maps are based on latent learning,
which becomes apparent when an incentive is given
(Tolman & Honzik, 1930).
36
Motivation

What motivates you?
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Motivation
Intrinsic Motivation: The desire to perform a
behavior for its own sake.
Extrinsic Motivation: The desire to perform a
behavior due to promised rewards or threats
of punishments.
Do you have any examples for either one?
38
Biological Predisposition
Photo: Bob Bailey
Biological constraints
predispose organisms to
learn associations that
are naturally adaptive.
Breland and Breland
(1961) showed that
animals drift towards
their biologically
predisposed instinctive
behaviors.
Marian Breland Bailey
39
Skinners Legacy
He stated with some controversy, by repeating
over and over that external influences shape
behavior and by urging the use of operant
principles to influence people’s behavior at
school, work, and home.
40
Applications of Operant Conditioning
Reinforcers affect productivity. Many
companies now allow employees to share
profits and participate in company ownership.
At work
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Operant vs. Classical Conditioning
42
Learning by Observation
© Herb Terrace
Higher animals,
especially humans, learn
through observing and
imitating others.
©Herb Terrace
The monkey on the right
imitates the monkey on
the left in touching the
pictures in a certain
order to obtain a
reward.
43
Reprinted with permission from the American
Association for the Advancement of Science,
Subiaul et al., Science 305: 407-410 (2004)
© 2004 AAAS.
Mirror Neurons
Neuroscientists discovered mirror neurons in
the brains of animals and humans that are
active during observational learning.
44
Learning by observation
begins early in life. This
14-month-old child
imitates the adult on TV
in pulling a toy apart.
Meltzoff, A.N. (1998). Imitation of televised models by infants.
Child Development, 59 1221-1229. Photos Courtesy of A.N. Meltzoff and M. Hanuk.
Imitation Onset
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Bandura's Bobo doll
study (1961) indicated
that individuals
(children) learn
through imitating
others who receive
rewards and
punishments.
Courtesy of Albert Bandura, Stanford University
Bandura's Experiments
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Applications of Observational Learning
Unfortunately,
Bandura’s studies
show that antisocial
models (family,
neighborhood or TV)
may have antisocial
effects.
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Positive Observational Learning
Bob Daemmrich/ The Image Works
Fortunately, prosocial (positive, helpful) models
may have prosocial effects.
48
Gentile et al., (2004)
shows that children in
elementary school who
are exposed to violent
television, videos, and
video games express
increased aggression.
Ron Chapple/ Taxi/ Getty Images
Television and Observational Learning
49
Modeling Violence
Children modeling after pro wrestlers
Glassman/ The Image Works
Bob Daemmrich/ The Image Works
Research shows that viewing media violence
leads to an increased expression of aggression.
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