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Chapter Six
Learning
Classical Conditioning
Operant Conditioning
Observational Learning
Part One: Classical Conditioning
Classical Conditioning is conditioning by association, such as a pet getting excited whenver she hears
a certain car arriving because she associates it with her owner coming home.
• Pavlov (1906)
• fundamental concepts
• further concepts
Watson & Rayner (1920)
• influencing factors
Rescorla (1968)
• special cases
Garcia & Koelling (1966)
Pavlov (1906)
Ivon Pavlov24 gave dogs specific stimuli, such as the ringing of a bell, several times, each immediately
prior to providing them with food. The dogs salivated because of the food. Later, the dogs would salivate at the sound of the bell, in anticipation of the food.
Fundamental concepts of classical conditioning
Term
Unconditioned Stimulus
(UCS)
Unconditioned Response
(UCR)
Conditioned Stimulus
(CS)
Conditioned Response
(CR)
Definition
stimulus that naturally causes
an unconditioned response
(without need for conditioning)
natural response to a stimulus
(without need for conditioning)
stimulus that does not naturally
cause a given response but does
after being paired sufficiently
with an unconditioned stimulus
response to a stimulus that does
not naturally elicit that response
Example
The smell of food is a natural
stimulus for dogs.
Dogs will naturally salivate
when they smell food.
The sound of a bell was paired
with food for Pavlov’s dogs.
The sound of a cart does not
naturally elicit salivation, but it
did for Pavlov’s dogs.
Further concepts of conditioning
Term
Acquisition
Stimulus Generalization
Stimulus Discrimination
Extinction
Spontaneous Recovery
Definition
Example
creating a conditioned behavior Pavlov’s dogs heard the bell
by pairing a CS with a UCS
each time right before being
fed.
responding to stimuli similar but Pavlov’s dogs would salivate
not identical to the CS
even if the bell-ringing was
louder or higher pitched.
not responding to stimuli
Pavlov’s dogs would not salivate
different from the CS
to the sound of a horn.
eliminating a CR by consistently After receiving no meat powder
presenting the CS without the after several bell ringinings,
UCS
Pavlov’s dogs would unlearn the
CR.
regaining a CR after a rest period Days after the CR was
following extinction
extinguished, a ringing bell may
again elicit a CR.
Watson & Rayner (1920)
John Watson17 and Rosalie Rayner let an 11month-old infant, Little Albert, play with a
fluffy white rat. Each time he reached for it, they
scared him with a very loud noise from a hammer
and metal. Later they gave him the rat unaccompanied by the noise, and did the same with similar items.
Term
For Little Albert
Unconditioned Stimulus
The loud noise was naturally scary.
Unconditioned Response
He naturally experienced fear from the noise.
Conditioned Stimulus
The noise elicited fear now that it was paired with the rat.
Conditioned Response
He developed a fear of the rat.
Stimulus Generalization
He also showed a fear response to a fluffy rabbit, a Santa Claus
mask, Watson’s white hair, etc.
Stimulus Discrimination
He showed less fear response to a dog, and none to people’s hair
that wasn’t white.
Extinction
Eventually his conditioned fear of rats and related things might
fade as he experienced them not paired with scary noises.
Factors influencing classical conditioning
In most cases, there are two factors that
are essential for classical conditioning to
take place: The unconditioned stimulus
should be more likely to occur after an
occurance of the conditioned stimulus
than at another random time, and it
should be immediate rather than delayed. As an example, consider the episode from The Office in which Jim offered
Dwight an altoid each time his computer
made a restart sound.
Term
Optimal conditions
Temporal Contiguity
The UCS immediately follows
the CS.
Contingency
The UCS has a higher probability
following an instance of the CS
than at another random time.
How Jim could have failed
letting time elapse between the
sound and the altoid offering
sometimes not offering an altoid
after the tone, and sometimes
offering an altoid without the
tone
Rescorla (1968)
Participants: 24 rats
Procedure: Over a five-day conditioning period, rats experienced a series of 12 two-minute tones,
each followed by eight minutes without a tone. During some of these tones they received a ½-second
shock.
Independent Variable: contingency—received no additional shocks, or also received shocks at
random times without the tone
Dependent Variable: conditioned fear of the tone
Results: The rats that experienced shocks only when they
heard the tone were conditioned
to fear the tone, but the others
were not.
Conclusion: For the rats to be
conditioned to fear the tone, they
had to know that the shock would
not happen without it.
Special cases of classical conditioning
Term
Higher-Order
Conditioning
Conditioned Taste
Aversion
Definition
Distinction
Example
using a CS as a UCS to The CS is never actually A rat conditioned to
create a CR to a new CS paired with a true UCS. fear a red light because
an electric shock
will follow can be
conditioned to fear a
blue light because a red
light will follow.
conditioning pairing
The UCS can happen
Carli got sick after
taste or smell with
long after the CS, and drinking tequila; now
nausea
can be effective after she feels sick at the
just one pairing.
smell of it.
Garcia86 & Koelling (1966)
Participants: 10 rats
Procedure: Punishment was applied for drinking water with a specific characteristic.
Independent Variable I: unique aspect of water—gustatory or audio-visual
Independent Variable II: type of punishment—nausea or shock
Independent Variable III: delay before punishment—none or 20 minutes
Dependent Variable: avoidance of water
Results: In the audio-visual condition, only shock caused avoidance, and only minimally so in the
delayed punishment condition. In the gustatory condition, only nausea caused avoidance, but did so
equally in the immediate and delayed condition.
Conclusion: When punishment results from eating, making the results not immediately known, the
effects were linked even though they did not occur until much later. Without this, it would be impossible to learn what is dangerous and should be avoided.
Part Two: Operant Conditioning
Operant Conditioning is conditioning through reinforcement and punishment, such as circus animals
learning tricks by getting treats when they perform a desired behavior. It is called operant conditioning
because it is based on organisms operating on their enviornment to effect a desired outcome (or avoid
an undesired one), as opposed to classical conditioning which is more automated.
• fundamental concepts
Project Pigeon
• special cases
Seligman & Meier (1967)
Fundamental concepts of operant conditioning
B. F. Skinner1 developed an “operant chamber” (later commonly called a Skinner Box) in which
reinforcements and punishments could be administered to an animal in response to specific behaviors.
Term
Definition
Skinner Box Example
Positive Reinforcement
making a behavior more likely A rat gets food by pushing a
by adding a desirable stimulus lever whenever a green light
comes on.
Negative Reinforcement
making a behavior more likely A rat prevents getting shocked
by removing an undesirable
by pusing a lever whenever a
stimulus
green light comes on.
Punishment
making a behavior less likely
A rat gets shocked whenever he
pushes a lever while a red light
is on.
Project Pigeon
B. F. Skinner1 headed a World War II effort to create a missile-guidance
system operated by pigeons (Skinner, 1960). The pigeons were trained
to steer the missile by pecking at a target projected onto a touch screen
triggered by interruptions in airflow. Test simulations showed the system to be highly effective.
Special cases of operant conditioning
Term
Shaping
Definition
conditioning
successively more
specific behaviors
Learned Helplessness conditioned failure
to attempt to remedy
unpleasant situations
due to previous
exposure to other
unpleasant situations in
which the organism had
no control
Distinction
The criterion required
for reinforcement
gradually increases in
scope.
The organism is
conditioned to be
helpless in general,
including in contexts
unrelated to the
original conditioning.
Example
A bear is reinforced for
coming near a tricycle
until he learns to do
so; then he is rewarded
for sitting on it, then
for putting his feet on
the pedals, then for
pushing the pedals.
A student who loses
her job and is unable
to get a new one gives
up in general and
stops studying for her
midterms.
Seligman31 & Maier (1967)
shocks avoided later
Participants: 24 dogs of no specific breed
Procedure: Each dog in the two experimental conditions was placed
in a box in which the lights would periodically go out, signaling an
oncoming shock. In the escape condition, the dog could avoid the
shock by pressing a panel. In the learned helplessness condition, the
dog could not control the shocks, which were matched in duration to those received in the escape condition. The next day, each each dog was placed in a different box. For each of 10 trials, the dog would be
shocked if he did not jump to the other side of this box when the lights went out.
Independent Variable: original conditioning—
100%
none, escape, or learned helplessness
75%
Dependent Variable: learning to escape the shock
in the second box
50%
Results: Dogs that learned they had no control in the
25%
first situation did not attempt to learn how to escape
the shocks in the next situation.
0%
none escape learned
helplessness
Conclusion: Appropriate feelings of helplessness can
original conditioning
carry over to contexts in which they are not appropriate.
Part Three: Observational Learning
Observational Learning is learning by observing others’ behaviors and their consequences. A person
being observed in this way is called a model.
• Bandura, Ross, & Ross (1961)
• fundamental concepts
statement on media violence
Bandura31, Ross & Ross (1961)
mean physical imitative
aggression score
Participants: 36 boys and 36 girls, ages 3 to 5, from Stanford Nursery
Procedure: While the child did artwork in one corner of a room, an adult played with tinker toys in another. In the aggressive condition, after a minute the adult attacked a bobo doll. After 10 minutes, the
experimenter took the child to a new toy room, but after allowing a moment’s play induced frustration
by stating that these toys were reserved for others. Finally, the child was taken to a room with a bobo
doll and other toys.
Independent Variable I: aggression of model—none or bobo doll attack
Independent Variable II: sex of child
Independent Variable III: sex of model—same
30
aggressive model
as child or different
nonaggressive model
20
Dependent Variable: aggressive acts imitating
the model
10
Results: Children tended to imitate adults’ aggressive behaviors, especially physical aggression
0
child:
male
female
for boys and verbal aggression for girls. Both sexes
model:
samedifferentsamedifferent
were more likely to imitate same-sex models.
sex
Conclusion: Children learn by watching others.
Fundamental concepts of observational learning
Term
Attention
Retention
Ability
Motivation
Definition
being aware of another’s behavior and
its consequences
remembering what was observed
being able to reproduce the observed
behavior
believing that reproducing the
behavior will provide positive
consequences
Example from Bobo doll
The kids watched the adult’s aggressive
behavior.
The kids remembered the adult’s
general aggression and details of it.
The kids could easily mimic the adult’s
behavior.
The kids had an outlet for their
frustration of having toys taken away.
Joint statement to congress on media violence
In 2000, the six major organiztions listed below provided a joint statement to congress on the effects of
media violence, including the excerpts quoted below.
“At this time, well over 1000 studies point overwhelmingly to a causal connection between media violence and aggressive behavior in some children. The conclusion of the public health community, based
on over 30 years of research, is that viewing entertainment violence can lead to increases in aggressive
attitudes, values and behavior, particularly in children.” In particular, exposure to media violence is
believed to increase…
acceptance of
“Children who see a lot of violence are more likely to view violence as an
violence
effective way of settling conflicts.”
emotional
“Viewing violence can decrease the likelihood that one will take action on
desensitization
behalf of a victim when violence occurs.”
fear
“Viewing violence increases fear of becoming a victim of violence, with a
resultant increase in self-protective behaviors and a mistrust of others.”
acts of violence
“Children exposed to violent programming at a young age have a higher
tendency for violent and aggressive behavior later in life than children who
are not so exposed.”
• American Medical Association
• American Academy of Pediatrics
• American Psychiactric Association
• American Academy of Family Physicians
• American Psychological Association
• American Academy of Child & Adolescent Psychiatry