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Learning
Adaptation to the Environment
• Learning—any process through
which experience at one time can
alter an individual’s behavior at a
future time
• A relatively permanent change in
behavior due to experience
Behaviorism
• The view that psychology should restrict
its efforts to studying observable
behaviors, not mental processes.
• Founded by John Watson
– Thought that all human behavior is a result of
conditioning or due to past experience and
environmental influences.
– Claimed he could take any child and train him
to become any type of specialist.
Classical Conditioning
• A type of learning where a stimulus gains the
power to cause a response because it predicts
another stimulus that already produces that
response
• OR to put it simply: When an animal learns to
do a natural reflexive response to something
that it would normally not do the response to.
• Form of learning by association
Stimulus-Response
• Stimulus - anything in the
environment that one can respond to
• Response – any behavior or action
Stimulus-Response Relationship
Stimulus-Response Relationship
Ivan Pavlov (1849–1936)
Pavlov’s Dogs
• Digestive
reflexes and
salivation
• Psychic
secretion
Pavlov’s Research Apparatus
Ivan Pavlov
• Watch “Pavlov’s Discovery of Classical
Conditioning” Video #6 from Worth’s
Digital Media Archive for Psychology.
• Click on link below to view.
Classical Conditioning
NEUTRAL STIMULUS
will
elicit
NO REACTION
UNCONDITIONED STIMULUS
will
elicit a
Unconditioned
REFLEX ACTION
Response
will
elicit a
Unconditioned
REFLEX ACTION
Response
will
elicit a
CONDITIONED
RESPONSE
UNCONDITIONED STIMULUS
NEUTRAL STIMULUS
CONDITIONED
CONDITIONEDSTIMULUS
STIMULUS
Neutral Stimulus—Bell
• Does not normally elicit (cause) a
response or reflex action by itself
– a bell ringing
– a color
– a furry object
Unconditioned Stimulus—Food
• Always elicits a reflex action: an
unconditioned (unlearned) response
– food
– blast of air
– noise
Unconditioned Response
—Salivation
• The automatic response to the
unconditioned stimulus
• A response to an unconditioned stimulus—
naturally occurring & not learned
– Salivation at smell of food
– Eye blinks at blast of air
– Startle reaction in babies
Conditioned (Learned) Stimulus —
Bell
• The stimulus that was originally
neutral becomes conditioned after
it has been paired with the
unconditioned stimulus
• Will eventually cause the
unconditioned response by itself
Conditioned (Learned) Response
- Salivation
• The original unconditioned response
becomes conditioned after it has been
caused by the neutral stimulus
• Usually the same behavior as the UCR
Pavlov’s Experiment
Pavlov’s Experiment
Pavlov’s Experiment
Classical Conditioning Terms
•
•
•
•
•
Aquisition
Extinction
Spontaneous recovery
Generalization
Discrimination training
Acquisition
• The process of developing a learned
response
• The initial learning that takes place in
the during stage of conditioning when
the animal starts to associate the NS
with the US.
Acquisition
Extinction
• The diminishing of a learned response
• When the CS is continually presented
without the UCS then the CR will
eventually begin to disappear.
Extinction
Spontaneous Recovery
• The reappearance, after a rest period,
of an extinguished conditioned
response
• After a period of time if the CS is
presented, the CR returns.
• Learning may disappear but is not
eliminated.
Spontaneous Recovery
Generalization
• Process in which an organism
produces the same CR to two similar
stimuli (CS)
• The more similar the substitute
stimulus is to the original used in
conditioning, the stronger the
generalized response
Generalization
Discrimination
• Ability of an animal to not respond to
a new CS that is too different from the
original CS.
• The subject learns that one stimuli
predicts the UCS and the other does
not.
John B. Watson and Little Albert
• 11-month-old infant
• Watson and his assistant, Rosalie Rayner,
classically conditioned Albert to be frightened of
white rats
• Led to questions about experimental ethics
To Watch a Short Video on
Watson and the Little Albert
experiment click HERE. (4 min)
Little Albert – Before
Conditioning
Little Albert – During
Conditioning
Little Albert – After Conditioning
Little Albert - Generalization
Could Little Albert’s Fear Have
Been Undone?
• YES!!! Through Counter Conditioning!
• Must pair the conditioned stimulus (Rat)
with something that is incompatible with
fear (Candy).
BEFORE:
Rat
Fear
CS = CR
DURING:
Rat Candy Happy
CS + UCS = UCR
AFTER:
Rat
Not Scared
CS = New CR
Candy Happy
UCS = UCR
Classical Conditioning
&
Drug Use
Responses Similar to the Drug’s Effect:
Classically Conditioned Drug Effect
• Drugs that are regularly used to restore normal
functioning produce a conditioned response (CR) similar
to the drug’s effect. (see diagram below)
• This can result in a Placebo Response – a psychological
& physiological reaction to a fake treatment or drug.
– You feel more alert after drinking decaffeinated coffee
Responses OPPOSITE to the Drug’s Effect:
Classically Conditioned Compensatory Response
• Drugs that are regularly used to disrupt normal
functioning produce a conditioned compensatory
response (CCR) opposite to the drug’s effect.
• This is caused by your body naturally trying to
compensate and restore normal functioning.
• Eventually, stimuli that reliably precede the
administration of a drug cause a physiological
reaction that is opposite to the drug’s effects.
• May be one explanation for the characteristics of
withdrawal and tolerance
The Conditioned Compensatory Response
Siegel’s CCR Studies
• If a drug abuser does their drug in an
unfamiliar setting they will run the risk of
overdose because they will not have the
CCR effect before they take the drug.
• Spontaneous recovery is a reason people
relapse when they find themselves in a
similar situation to the one in which they
regularly used the drug.
Siegel’s Rat Study
• Over the course of a month, rats gradually
developed tolerance to increasing amounts of
heroin.
• Then, they were injected with an overdose of
almost twice as much heroin as they had
become accustomed to receiving.
• Rats that were injected with the heroin
overdose in the same setting in which they had
previously received heroin were twice as likely
to survive as were rats that were injected in a
different setting.
• Almost all the rats in the control group that had
not previously been exposed to heroin died.
CCR & Drug Overdose
• Some heroin addicts have died after
injecting their usual amount of heroin in an
unfamiliar environment. Why?
Cognition and
Biological
Predispositions:
Does Classical Conditioning change what the
animal knows as well as its behavior?
Robert Rescorla (1940-
)
• Developed a theory emphasizing the
importance of cognitive/mental
processes in classical conditioning
• Pointed out that subjects had to
determine (think) whether the NS/CS
was a reliable predictor of the UCS
– The Bell was a reliable predictor that
Food would follow.
Rescorla’s Experiment
•Group 1 found the tone to be a reliable predictor of the shock and as a
result their heart rates increased each time they heard it.
•Group 2 experienced 20 random shocks with no tone in addition to the
original 20 shocks with a tone. They had a much smaller fear response to
the tone because it was not a reliable predictor of the shock.(pg. 200-201)
Evolutionary Perspective
Biological Preparedness & Phobias
Martin Seligman
• We are biologically predisposed to learn things that affect
our survival.
• We are predisposed to avoid threats our ancestors faced-food that made us sick, storms, heights, snakes, etc.
– People more easily acquire conditioned fear responses to pictures
of snakes & spiders when paired with electric shocks than they do
with flowers and mushrooms.
– Monkeys will learn a fear response to snakes & crocodiles but not
to flowers and toy rabbits.
• But not modern-day threats—knives, stoves, cars, water
pollution, etc.
– Recent studies showed that children like Little Albert could NOT
be classically conditioned to fear things like wooden blocks &
curtains.
Taste Aversion
John Garcia
(1917- )
• Rats drank flavored water (NS) and hours later
were given a shot with a drug (UCS) that made
them sick (UCR). The rats refused to drink the
flavored water again.
• Subjects become classically conditioned to avoid
specific tastes, because the tastes are associated
with nausea.
**Differs from other Classical Conditioning in that:
•It did NOT require repeated pairings of a NS and UCS.
•The time span between the two was a few hours.
•Rats were conditioned to taste and not anything else that
occurred in the hours between when they drank the flavored
water and got sick.
How Taste Aversion Works:
BEFORE
Flavored
Water
Drug
NS = No Response
DURING:
Flavored
Water Drug
Nausea
NS + UCS = UCR
AFTER:
Flavored
Water Avoidance
CS = CR
Nausea
UCS = UCR