Download Module 26: Classical Conditioning

Learning
Module 26
Adaptation to the Environment
• Learning— the process of acquiring new
behavior & knowledge/info that is
relatively permanent
• A relatively permanent change in behavior
and/or knowledge due to experience
Learning by Association
• Most learning comes from association – we connect
events that occur in sequence.
• Hearing one song on a playlist cues you to what song is
coming next.
• When behaviors are repeated in a certain
context/environment/situation, the behavior becomes
associated with that context
– Over time the repeated behavior becomes a habit when you are in
that situation/context.
– The situation/context triggers the habitual behavior associated
with it. (Takes about 66 days to form a habit)
– Associative Learning = predicting the immediate future
• We accurately guess what’s coming next by linking two events together.
Habituation vs. Adaptation
Adaptation is recoverable. Habituation is not.
• Habituation – reduced
sensitivity to a stimulus,
even if the stimulus
changes.
• Our reaction is strong at first
but not when the stimulus or
something like it happens
again.
• A turtle draws its head back
into its shell when its shell is
touched. After being touched
repeatedly, the turtle realizes
it’s not in danger and no longer
hides. – It has habituated. (see
more examples)
• Adaptation – Your
reduced sensitivity to an
unchanging and constant
stimulus.
• You don’t notice the cool
water after you’ve been in the
lake.
• Don’t notice a watch on your
wrist but when you move it,
you suddenly notice it again.
• If the stimulus changes, your
sensitivity to it goes back to
its original level
Behaviorism
• The view that psychology should restrict its efforts to
studying observable behaviors, not mental processes.
• Founded by John B. 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 formerly neutral
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 Relationship
• Stimulus - anything in the environment that one can respond to
• Response – any behavior or action
You quickly realize
that the “flush”
predicts hot water.
Stimulus-Response Relationship
After linking the two stimuli
together, the originally neutral
“flush” elicits/causes a response.
You’ve learned by association!
Ivan Pavlov (1849–1936)
Pavlov’s Dogs
• Studied digestive
reflexes and salivation
• “Psychic secretions”
were made by dogs to
things like seeing the
researcher or hearing
their approaching
footsteps.
Pavlov’s Research Apparatus
Ivan Pavlov
• Watch “Pavlov’s Discovery of Classical
Conditioning” (3 min) - online
– Video #6 from Worth’s Digital Media Archive for Psychology.
– Click on link below to view.
Neutral Stimulus — Bell
Neutral Stimulus
=
No Response
• Exists BEFORE conditioning/learning
has occurred
• Does not normally elicit (cause) a
response or reflex action by itself
– a bell ringing
– a color
– a clicking metronome
• None of these would naturally cause a dog to salivate.
Unconditioned Stimulus — Food
Unconditioned Stimulus
=
• Always elicits/causes a reflexive
action: an unconditioned (unlearned)
response
– Food causes salivating
– blast of air causes blinking
– Loud noise causes one to startled or scared
Unconditioned Response — Salivating
Unconditioned Stimulus
=
Unconditioned
Response
• The automatic/natural 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
Conditioned Stimulus
=
• The stimulus that was originally neutral becomes
conditioned or learned after it has been paired
repeatedly with the unconditioned stimulus
• Will eventually cause the unconditioned response
by itself
– The Bell predicts food is coming so the dog salivates
– What was once neutral is now learned/conditioned because it now
causes something to happen. Before it did not.
Conditioned (Learned) Response - Salivating
Conditioned Stimulus
=
Conditioned Response
• The original unconditioned response becomes
conditioned/learned after it has been caused by
the conditioned (previously neutral) stimulus
• Usually the same behavior as the UR
Classical Conditioning
NEUTRAL STIMULUS
(NS)
UNCONDITIONED STIMULUS
(US)
will
elicit
NO REACTION
will
elicit a
REFLEX ACTION
Unconditioned Response
(UR)
UNCONDITIONED STIMULUS
(US)
NEUTRAL STIMULUS
will
elicit a
(CS)
Unconditioned Response
(UR)
(NS)
CONDITIONED
CONDITIONEDSTIMULUS
STIMULUS
REFLEX ACTION
will
elicit a
CONDITIONED
RESPONSE (CR)
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/learning 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.
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
Different alarms still have the same effect = wake you up
Discrimination
• Ability of an animal to not respond to a new NS/CS
that is too different from the original CS.
• The subject learns that one stimuli predicts the
UCS and the other does not.
Where’s
the bell?
=
After learning to salivate to a bell, Pavlov’s dogs didn’t drool to other sounds.
Generalization vs. Discrimination
Higher-Order/Second-Order Stimulus
• A new NS gets
associated with
a previously
learned CS and
starts to trigger
the CR.
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.
Online version
(4 min)
Little Albert –
Before Conditioning
UCR
Little Albert –
During Conditioning
UCR
Little Albert –
After Conditioning
CS: rat
(CR)
Little Albert –
Generalization & Discrimination
(Generalization)
(Discrimination)
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).
Mary Cover Jones
• Notice how we start with a conditioned stimulus not a neutral stimulus
BEFORE:
Rat
Fear
CS = CR
DURING:
Rat Candy Happy
CS + UCS = UCR
AFTER:
Rat
Not Scared
CS = New CR
Candy Happy
UCS = UCR
Mary Cover Jones’ Peter Experiment
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?