Classical Conditioning

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Learning
(Conditioning)
Learning is how we Adapt to the
Environment
• Learning—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 a result of past experiences
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 naturally produces that
response
• OR to put it simply: When an animal learns a
natural reflexive response to something that it
would NOT NORMALLY respond to.
• 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
Classical Conditioning
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.
– 3:00 clip
Neutral Stimulus
• Does not normally elicit (cause) a
response or reflex action by itself
– a color
– a furry object
• What was the NS in Pavlov’s
Experiment?
• Bell
Unconditioned Stimulus
• Always elicits a reflex action: an
unconditioned (unlearned) response
– blast of air
– Noise
• What was the UCS in Pavlov’s
Experiment?
• Food
Unconditioned Response
• The automatic response to the unconditioned
stimulus
• A response to an unconditioned stimulus—
naturally occurring & not learned
– Eye blinks at blast of air
– Startle reaction in babies
• What was the UCR in Pavlov’s
Experiment?
• Salivation
Conditioned (Learned) Stimulus
• 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
• What was the CS in Pavlov’s
Experiment?
• Bell
Conditioned (Learned) Response
• The original unconditioned response
becomes conditioned after it has been
caused by the neutral stimulus
• Usually the same behavior as the UCR
• What was the CR in Pavlov’s Experiment?
• Salivation
Pavlov’s Experiment
Pavlov’s Experiment
Pavlov’s Experiment
Classical Conditioning Terms
•
•
•
•
•
Acquisition
Extinction
Spontaneous recovery
Generalization
Discrimination training
Acquisition
• The initial learning that takes place in
the during stage of conditioning when
the animal starts to associate the NS
with the UCS.
• NS + UCS = UCR
Extinction
• The diminishing of a learned response
• When the CS is continually presented
without the UCS then the CR will
eventually begin to disappear.
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
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 (4:00) click HERE.
Little Albert – Before
Conditioning
•Watch “Watson’s Little Albert” Video
#7a from Worth’s Digital Media
Archive for Psychology.
– 13 seconds
Little Albert – During
Conditioning
Little Albert – After Conditioning
•Watch “Watson’s Little
Albert” Video #7b from
Worth’s Digital Media
Archive for Psychology.
– 14 seconds
Little Albert - Generalization
•Watch “Watson’s
Little Albert” Video
#7c from Worth’s
Digital Media
Archive for
Psychology.
– 17 seconds
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
How is classical conditioning
involved in the placebo effect?
• Individual expects a drug will work a
certain way and have a psychological and
physiological reaction to it.
• Regular use may produce “placebo
response” where user associates sight,
smell, taste with drug effect
Cognition and
Biological
Predispositions
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
Rescorla’s Experiment
When the rats in group 2 could not reliably predict when the
shocks would occur the result was they didn’t learn to fear the
tone. This shows they were using cognitive processes!
Evolutionary Perspective
Biological Preparedness
• We are predisposed to learn things that affect our
survival.
• Internal stimuli—associate better with taste
• External stimuli—associate better with pain
• The majority of phobias are about objects of natural
importance to the survival of the species.
• Animals seem to be biologically prepared to fear
certain types of stimuli that represent natural threats
to survival.
– We are predisposed to avoid threats our ancestors faced-food that made us sick, storms, heights, snakes, etc.
– But not modern-day threats--cars, water pollution, etc.
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
Flooding as a Cure for Phobias
(example of extinction)
• When a fear is disproportionate to the harm
it could cause, psychologists could use
flooding to cure phobias.
• Expose person to the harmless stimulus
repeatedly until fear becomes extinct.
• Drawbacks of this technique?
Systematic Desensitization
• People are taught relaxation techniques and are
gradually exposed to the stimulus causing fear.
• Example: Pictures of the stimulus (snakes), the actual
stimulus far away, the stimulus closer, and finally
holding/touching a snake.
• All the while, they are pairing the experience with
something NOT fearful and hopefully relaxing
• How Classical Conditioning is used for curing phobias:
Virtual Systematic Desensitization – video clip #31
from Scientific American Frontiers (9:31).
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