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Transcript
What Sort of Learning Does Classical
Conditioning Explain?
Classical conditioning is a
basic form of learning in which
a stimulus that produces an
innate reflex becomes
associated with a previously
neutral stimulus, which then
acquires the power to elicit
essentially the same response
Copyright © Allyn & Bacon 2007
I CAN
• Describe the key features of Classical
Conditioning:
• UCS
• UCR
• CS
• CR
• Acquisition
• Extinction
• Spontaneous Recovery
• Stimulus Discrimination/Generalization
The Essentials of Classical
Conditioning
• Neutral stimulus
Any stimulus that produces no
conditioned response prior to learning
• Examples; A bell sound is neutral…
It does nothing until paired
with a natural producing
stimulus, such as food
Copyright © Allyn & Bacon 2007
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
Copyright © Allyn & Bacon 2007
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
A stimulus that automatically
(without conditioning)
produces a reflexive behavior
In Pavlov’s experiment, food
was the UCS because it
produced a salivation reflex,
or UCR
Conditioned
response (CR)
Copyright © Allyn & Bacon 2007
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
The response elicited by
an unconditioned stimulus
without prior learning
It’s reflective and involved
NO LEARNING
Conditioned
response (CR)
Copyright © Allyn & Bacon 2007
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
A previously neutral
stimulus (a bell/tone)
elicits a conditioned
response
(dog salivating)
Copyright © Allyn & Bacon 2007
The Essentials of
Classical Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
A response to a previously
neutral stimulus that has
become associated with
the unconditioned stimulus
The dog salivates at the sound
of the bell
Copyright © Allyn & Bacon 2007
Ivan Pavlov
• Russian physiologist,
psychologist, and physician.
• Awarded the Nobel Prize in
Physiology or Medicine in
1904 for research pertaining
to the digestive system.
• Pavlov is widely known for
first describing the
phenomenon of classical
conditioning.
Copyright © Allyn & Bacon 2007
Pavlov’s Dog
• While doing
experiments on
salivation, he noticed
dogs salivated before
the food was in their
mouths
• He eventually came up
with an objective
model of learning….
classical conditioning
Ivan Pavlov
Copyright © Allyn & Bacon 2007
Copyright © Allyn & Bacon 2007
Copyright © Allyn & Bacon 2007
Classical Conditioning
Prior to conditioning
Neutral stimulus
(tone)
(Orientation to sound
but no response)
Unconditioned stimulus
(food in mouth)
Unconditioned response
(salivation)
Conditioning
Neutral stimulus
CS (tone)
+
Unconditioned stimulus
(food)
Conditioned response
(salivation)
After conditioning
Conditioned stimulus
(tone)
Conditioned response
(salivation)
Copyright © Allyn & Bacon 2007
Copyright © Allyn & Bacon 2007
• Watch the video
The Office - Pavlov's dog on You tube
Copyright © Allyn & Bacon 2007
Classical Conditioning in Humans
• The smell of perfume..
• a certain song…
• a specific day of the year…
When it results in intense emotions
• It's not that the smell or the
song are the cause of the
emotion, but rather what
that smell or song has been
paired with...
• …perhaps an ex-boyfriend
or ex-girlfriend, the death
of a loved one, or maybe
the day you met your
current husband or wife.
Acquisition
• The initial learning stage
of classical conditioning
• Refers to the period of time
when the stimulus (bell)
comes to evoke the
conditioned response.
(salivation)
Copyright © Allyn & Bacon 2007
Classical Conditioning
Extinction and Spontaneous Recovery
A Conditioned Response (CR ) is not
permanent… it can be reversed, or made
extinct
BUT….it may return spontaneously
Copyright © Allyn & Bacon 2007
Extinction
Weakening of a conditioned
response in the absence of an
unconditioned stimulus
• The dog salivating (CR) is eliminated by
repeated presentations of the bell (CS )
without the food (US)
Copyright © Allyn & Bacon 2007
Spontaneous Recovery
The reappearance of an extinguished,
conditioned response after a time delay,
usually at a lower intensity
• For example, cocaine addicts who are thought
to be "cured" can experience an irresistible
impulse to use the drug again if they
encounter a stimulus with strong connections
to the drug, such as a white powder
Copyright © Allyn & Bacon 2007
(1)
Acquisition
(CS + UCS)
(2)
Extinction
(CS alone)
(Time)
Trials
Copyright © Allyn & Bacon 2007
Rest period
Strength of the CR
(Weak)
(Strong)
Acquisition, Extinction, and
Spontaneous Recovery
(3)
Spontaneous
Recovery
(CS alone)
Classical Conditioning
Generalization and Discrimination
Stimulus Generalization
Giving a conditioned response
(panic) to stimuli that are
similar to the CS (spiders)
Stimulus Discrimination
Involves responding to one
stimulus but
not to stimuli that are similar
Copyright © Allyn & Bacon 2007
Stimulus Generalization
• Giving a conditioned response (panic)
to stimuli that are similar to the CS
(dogs)
Being bitten by a large dog results in
fear of all dogs
Copyright © Allyn & Bacon 2007
Stimulus Discrimination
• Responding to one
stimulus but
not to stimuli that
are similar
Being bitten by a
large dog results
in fear of only
large dogs, but not
all dogs
Copyright © Allyn & Bacon 2007
Experimental Neurosis
Confusing stimuli may cause experimental neurosis
A pattern of erratic behavior
when faced with difficult,
stressful, or demanding choices
Freakin’ Out
Copyright © Allyn & Bacon 2007
Applications of Classical
Conditioning
• Classical Conditioning
explains many
behaviors……such as
cravings, aversions, and
fears
• It is also useful in
eliminating unwanted
behavior
Copyright © Allyn & Bacon 2007
Systematic Desensitization
• A behavior therapy
used to treat phobias
• Example: Fear of
snakes
• The patient is first
taught a muscle
relaxation technique.
• Then he or she is told ,
over a period of days, to
imagine the fearproducing situation
while trying to restrain
the anxiety by
relaxation
• At the end of the series,
the strongest anxietyprovoking situation
may be brought to
mind without anxiety.
Copyright © Allyn & Bacon 2007
A Fear
of Snakes?
Once the patient had practiced
their relaxation technique, the
therapist would then present
them with the photograph, and
help them calm down.
• They would then
present increasingly
unpleasant situations:
• a poster of a snake
• a small snake in a box in
the other room
• a snake in a clear box in
view
• touching the snake
• At each step in the
progression, the patient
is desensitized to the
phobia using coping
techniques
• As they realize that
nothing bad happened
to them, the fear is
Copyright © Allyn & Bacon 2007
gradually extinguished.
Little Albert
By present-day
standards,
• Albert was
taught
to fear
a whitewas
rat
Watson's
experiment
when
was paired
unethical
for it
several
with a loud noise
reasons.
that scared the
child.
Albert's mother was not
• Thisoffear
informed
the was later
generalized to
experiment.
other
white
,
furry
It was performed without
objects
her consent.
Copyright © Allyn & Bacon 2007
Little Albert
Copyright © Allyn & Bacon 2007
Little Albert
• Albert's fear was not extinguished because
he moved away before systematic
desensitization could be administered.
• It is presumed that, although he still must
have had fear conditioned to many various
stimuli after moving, he would likely have
been desensitized by his natural
environments later in life.
Copyright © Allyn & Bacon 2007
Taste-aversion Learning
• A 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
Learned taste aversion may be
nature's way of keeping us away
from deadly foods.
Copyright © Allyn & Bacon 2007
Taste-aversion
• This poses a problem for
‘Classical’ conditioning
because it is not entirely
learned.
• It appears to be part of our
biological nature
• This leads some to question
some parts of Pavlov’s
theory
Copyright © Allyn & Bacon 2007
CAN I?
• Describe the key features of Classical
Conditioning:
• UCS
• UCR
• CS
• CR
• Acquisition
• Extinction
• Spontaneous Recovery
• Stimulus Discrimination/Generalization