Download Elicited Behavior and Classical Conditioning

Elicited Behavior and
Classical Conditioning
Chapter 3
Dr. Steven I. Dworkin
• For 2 days, Greg has resisted his urge to smoke. Having
attempted to quit on more occasions than he can count,
he's determined not to let his extreme nervousness and
irritability keep him from succeeding this time. His
family tries to distract his thoughts from cigarettes, but
these attempts work only temporarily. Anticipating
tonight's televised championship football game helped
him for a while, but even this cannot prevent his
recurrent, intense impulses to smoke (hard to believe
but it’s true).
Dr. Steven I. Dworkin
• Greg began smoking cigarettes when he was 15. All his
friends smoked, so it seemed like the natural thing to do. At
first, he did not like to smoke; it made him cough and
sometimes feel slightly nauseated. Greg smoked only with
his friends to feel part of the group, and he pretended to
inhale. However, as the unpleasant effects began to
disappear, he learned to inhale and began to smoke more. By
the age of 18, Greg smoked two to three packs of cigarettes
each .day. He never thought about stopping until he met
Paula. A nonsmoker, she tried to convince him to quit.
Finding himself unable to break his habit, he simply did not
smoke while with Paula. After they married, Paula
continued to plead with Greg to stop smoking. He has tried
every now and then over the past ten years to resist
cigarettes, usually avoiding his habit for a day or two. This
time had to be different.
Dr. Steven I. Dworkin
•
At age 35, Greg felt himself in perfect health, but a
routine check-up with the family physician several days
ago proved him wrong. Greg learned that his extremely
high blood pressure made him a prime candidate for a
heart attack. The doctor told Greg that he must lower
his blood pressure through special diet, medication, and
no smoking. Continued smoking would undoubtedly
interfere with the other treatments. The threat of a
heart attack frightened Greg; he had seen his father
suffer the consequences of an attack several years ago.
Determined now to quit, he only hopes he can endure
his withdrawal symptoms.
Dr. Steven I. Dworkin
Phylogenetic Behavior
• Behavioral relations based on genetic endowment.
• Acquired on the basis of species history.
• Repertoire of response evoked by environmental
conditions
Dr. Steven I. Dworkin
Elicited Behavior
• Reflex – relatively simple, involuntary response to a
stimulus.
– Salivation
– Eye blink
– Startle response
• Reflex Arc – neural structure that underlies many reflexes
consisting of a sensory neuron, an interneuron and motor
neuron.
Dr. Steven I. Dworkin
Reflexes
• Reflex- stereotyped pattern of
movement of a part of the body
that can be reliably elicited by
presenting the appropriate
stimulus
• Patellar reflex
Dr. Steven I. Dworkin
Sequences of Behavior
• Fixed action patterns
– Sequences of behavior phylogenetic in origin.
– All members of species (sex) engage in behavior
(species-specific behavior).
– Behavior evoked by sign stimuli or releasers.
– Initiated sequence is repeated even if evoking stimulus
is removed.
Dr. Steven I. Dworkin
Habituation
• A decrease in the strength of an elicited behavior following repeated
presentations of the eliciting stimulus.
• Decline in the tendency to respond to a stimulus once it has become
“familiar”
– Simplest form of learning
– Advantage: provides constraints on what will cause alarm.
– Low intensity stimulus ?
– Stimulus-specific
– Gradual changes
– Drug effects (tolerance)
– Dishabituation
Dr. Steven I. Dworkin
Habituation Therapy of Tinnitus
• Train the brain to classify tinnitus-related neuronal activity
as representing a neutral, nonsignificant signal, then the
process of habituation will occur automatically. To achieve
this, it is necessary, however, to fulfill two basic
conditions:
– Removal of the negative association attached to tinnitus
perception.
– Preservation of tinnitus detection (but not necessary
perception) during treatment.
Dr. Steven I. Dworkin
Sensitization
• Increase in strength of an elicited behavior following
repeated presentation of the eliciting stimulus.
• High intensity stimulus?
• Generalizes to other stimuli (PTSD).
• Discrete changes
• Drug effects
Dr. Steven I. Dworkin
Emotion
• Our common experience of emotions is that they are
elicited by a stimulus, reach some peak, and then gradually
return to baseline.
• This gradual diminution of an emotion could be a form of
habituation -- the emotion wanes because we "get used"
to the situation (or, perhaps because the supply of
neurotransmitter is exhausted).
Dr. Steven I. Dworkin
Opponent Process Theory
• Opponent process theory suggests that any given emotion
also has an opposed emotion.
• Activation of one member of the pair automatically
activates the opposite emotion
• The opposing emotion serves to diminish the intensity of
the initial emotion.
• Thus, the normally brief duration of intense emotions.
Dr. Steven I. Dworkin
Opponent Process Theory
• Thus, opponent process theory is a variant of a
homeostatic model -- input A (e.g. fear stimulus) triggers
an action (process B; e.g. tranquility) which reduces the
effect of the input.
• The outcome of this process as applied to emotions is that
no emotion is allowed to be intense for very long.
Dr. Steven I. Dworkin
Opponent Process theory
• The theory of Solomon and Corbitt assumes two further
characteristics of the opponent process -- it is strengthened
with use and it is conditionable.
• The implications of the strengthening process include the
prediction that, with repeated evocation, the initial emotion
should decrease in intensity.
Dr. Steven I. Dworkin
Opponent-Process Theory
• Solomon and Corbit (1974)
– The opponent-process theory states that when one
emotion is experienced, the other is suppressed. For
example, if you are frightened by a mean dog, the
emotion of fear is expressed and relief is suppressed. If
the fear-causing stimulus continues to be present, after
a while the fear decreases and the relief intensifies.
Dr. Steven I. Dworkin
Opponent Process Theory
Dr. Steven I. Dworkin
Opponent Process Theory
• Problems with the theory:
– what are the durations of the A and B process?
– why isn’t there an opponent to the B process, etc.
– how does the strengthening of the B process take place
(what are the mechanisms)
– does it apply to all emotions or peculiarly to strong
negative emotions
Dr. Steven I. Dworkin
Reflexive Behavior
• Organisms are born with an array of responses that are
elicited by specific stimuli.
• These do not depend on an individual’s history and are
thus “unconditioned.”
– The stimuli are termed – unconditioned stimuli or US
– The responses are termed – unconditioned responses or
UR
Dr. Steven I. Dworkin
Pavlov and Classical Conditioning
• Ivan Pavlov was a physiologist who won a Nobel Prize for
his research on digestion.
• His original description of classical conditioning was a byproduct of this research. He did not set out to discover
classical conditioning.
Dr. Steven I. Dworkin
Dr. Steven I. Dworkin
Dr. Steven I. Dworkin
Pavlov
Dr. Steven I. Dworkin
Classical Conditioning
• Pavlov noticed that the dogs he used to do his research
salivated upon the sight of the lab workers who fed them.
– He concluded that this reflex was “psychological”
because it was based on the dog’s previous experiences.
– Further testing demonstrated that the sight of food
produced the same effect as giving the same amount of
food to the dog.
Dr. Steven I. Dworkin
Classical Conditioning
• Based upon his tentative acceptance of the salivation as a
reflex, Pavlov used the term conditional reflex to describe
this response.
• The term was mistranslated into English as conditioned
reflex, a mistake that helped create the terminology we use
to describe classical conditioning.
Dr. Steven I. Dworkin
Classical Conditioning
• Pavlov started with the unconditioned reflex of salivation
to food. He hypothesized that that this was an automatic
connection.
– The dogs had an unconditioned reflex between food
and secretion of digestive juices.
• A buzzer is called a neutral stimulus because it elicits
attention to the sound, but no automatic connection.
– The dogs would lift their ears and look around when the
buzzer sounded, but no salivation was produced.
Dr. Steven I. Dworkin
Classical Conditioning
• He conjectured that animals develop new connections by
transferring a response from one stimulus to another.
– He hypothesized that if a buzzer always preceded the
food, the buzzer would begin to elicit the reflex of
salivation.
• After a few pairings of the buzzer with the food, the dogs
would begin to salivate as soon as the buzzer sounded.
Dr. Steven I. Dworkin
Figure
With classical
conditioning a
conditioned
stimulus is
followed by an
unconditioned
stimulus. At first
the conditioned
stimulus elicits no
response, and the
unconditioned
stimulus elicits the
unconditioned
response. After
sufficient pairings
the conditioned
stimulus begins to
elicit the
conditioned
response, which
can resemble the
unconditioned
response.
Dr. Steven I. Dworkin
Classical Conditioning
• Terminology
– Unconditioned Stimulus (UCS)  An event that
consistently and automatically elicits an unconditioned
response.
– Unconditioned Response (UCR)  An action that the
unconditioned stimulus automatically elicits.
Dr. Steven I. Dworkin
Classical Conditioning
• Terminology
– Conditioned Stimulus (CS)  Formerly the neutral
stimulus, having been paired with the unconditioned
stimulus, elicits the same response. That response
depends upon its consistent pairing with the UCR.
– Conditioned Response (CR)  The response elicited
by the conditioned stimulus due to the training. Usually
it closely resembles the UCR.
Dr. Steven I. Dworkin
Classical Conditioning
• Factors that enhance conditioning
– Conditioning occurs more rapidly when the conditioned
(neutral) stimulus is relatively unfamiliar. If you are
already habituated to (used to) the neutral stimulus, it
will take longer for its pairing with an unconditioned
stimulus to form a connection for you.
– Conditioning is facilitated when people are already
aware of the connection between the CS and the UCS.
When people are informed of the conditioning
procedure prior to its beginning, they will be
conditioned faster.
Dr. Steven I. Dworkin
Respondent Conditioning
Transfer of behavior control from one stimulus to another or induction of
control from one stimulus to another.
US
UR
(Salivation)
(Food in mouth)
CS
CR
(Light)
(Salivation)
Dr. Steven I. Dworkin
Laws of the Reflex
• Law of threshold - stimulus intensity below which no response is
elicited and above which a response always occurs. A stimulus
intensity that elicits a response 50% of the time.
• Law of intensity-magnitude – As the intensity of US increases the
magnitude of the UR increases.
• Law of latency – As the intensity of the US increases, the latency to
the appearance of the evoked UR decreases.
Dr. Steven I. Dworkin
Appetitive and Aversive Conditioning
• Appetitive conditioning – US is an environmental event
the organism will seek.
• Aversive conditioning – US is an environmental event the
organism will typically escape from or avoid.
– Occurs more rapidly
– CER – conditioned emotional response
• Suppression ratio
• An aversive US can become an appetitive CS and an
appetitive US can become an aversive CS
Dr. Steven I. Dworkin
Excitatory and Inhibitory Conditioning
• Excitatory conditioning - NS is associated with
presentation of US
• Inhibitory conditioning – NS is associated with absence of
US
Dr. Steven I. Dworkin
Respondent Conditioning
• Acquisition
– Magnitude of CR increases over repeated pairings
– Asymptote for CR
– Asymptote for CR function of intensity of US
• Extinction
– Repeated presentation of CS only results in a decrement
of CR
Dr. Steven I. Dworkin
Temporal Relationships
US (Food)
CS (Light)
Time
Dr. Steven I. Dworkin
Temporal Relations and Conditioning
A) Delay
C) Trace
US
US
CS
CS
B) Simultaneous
D) Backward
US
US
CS
CS
Dr. Steven I. Dworkin
Respondent Conditioning
• Extinction
• Spontaneous Recovery
– Increase in CR after extinction after passage of time.
• Internal inhibition (Pavlov blocking of CS-CR
relationship)
• CS-CR relationship weakened (Behavioral
Analysis).
Dr. Steven I. Dworkin
Generalization
Salivation (in cc’s)
• CR occurs to values of CS not trained during acquisition.
1
0.5
0
75 150 225 300 375 450 525 600 675
Dr. Steven I. Dworkin
Discrimination
• CR to one stimulus but not to other similar events.
• Peak Shift
Dr. Steven I. Dworkin
Second Order Conditioning
• CS1 paired with US
• CS2 paired with CS1
• Suppression ratio
– Resp tone/resp no tone
Dr. Steven I. Dworkin
Applications
• Systematic Desensitization
• Treatment of Drug Abuse
Dr. Steven I. Dworkin