Elicited behavior, Habituation,
and Sensitization
Non-Associative Learning/Behavior
Elicited behavior - reflex, modal action pattern.
Repeated stimulation - habituation, sensitization.
Emotional behavior - pattern of affective dynamics.
Elicited Behavior
Reflex - Response elicited by a specific stimulus. Salivation, knee jerk, etc.
Elicited Behavior
Modal Action Pattern (MAP) – Orderly sequence of
reflexive behaviors.
Concept put forth by ethologists Tinbergen and Lorenz.
Species typical behavior, e.g., feeding, mating, social behaviors, etc.
Evolutionarily important behaviors, “instinctive”
Elicited by complex array or sequence of stimuli.
Elicitation can depend on motivation (“action-specific energy”)
Modal Action Pattern
Video of egg retrieval in goose
What is the sign stimulus?
MAPs in Humans?
• Lorenz claimed that caring for young (and the
associated affective responses) are MAPs.
• The sign stimuli are:
–
–
–
–
–
–
–
–
Head large in proportion to the body
Protruding forehead large in proportion to the size of the rest of the face
Large ears and eyes below the midline of the head
Small nose
Short thick extremities
Rounded body shape
Soft elastic body surfaces
Round protruding cheeks
Stephen Jay Gould on the
evolution of Mickey Mouse
Supernormal stimulus
An accurate 3-dimensional model of a herring gull's
head (a), and a 'supernormal' bill (b).
Supernormal stimulus
Supernormal stimuli?
v.
Repeated stimulation
Repeated stimulation
Elicited behavior is not plastic, but can change
with repeated stimulation.
Habituation effect
Decreased response with repeated stimulation.
Sensitization effect
Increased response with repeated stimulation.
Habituation effect
Response
Trials
Habituation movie
Rat hears a series of loud bursts of noise
Dishabituation
Dishabituation effect
Response
Trials
Dishabituation movie
Rat hears a series of loud high-pitched noises,
Followed by a loud lower-pitched noise,
Followed by another series of loud high-pitched noises
Spontaneous recovery
Retention Interval
Response
Trials
Location of habituation processes
Sensory
adaptation
Habituation
Fatigue
How is habituation different from sensory
adaptation and fatigue?
• Sometimes the habituated response will not recover
after for a long time. (Long Term Habituation)
Day
Day 11
Responses
to
Stimulus
Day
Day 21
21
Repeated Trials
of stim
Repeated Trials
of stim A
• Habituation will be slower for stimuli which
have a higher salience (i.e., intensity)
Resp
Resp to
to weak
weak
coffee
coffee flavor
flavor
Resp
Resp to
to Strong
Strong
coffee
coffee flavor
flavor
Responses
to
Stimulus
Repeated Trials
Repeated Trials
• Dishabituation following the presentation of a
novel stimulus.
Present
Response
Response to
to Present
Stimulus
Stimulus B
B
stimulus
stimulus A
A
(light)
(light)
(tone)
(tone)
Responses
to
Stimulus
Response
Response to
to
stimulus
stimulus A
A
(tone)
(tone)
Repeated Trials
• Generalization gradient of a habituated
response.
Responses
to
Stimulus
1700
1800 1900
2000 2100
2200 2300
Tone frequency of test stimulus following
habituation at 2000 Hz
Short-Term v. Long-Term Habituation
Days 1 - 11
Leaton (1976)
Day 12
Day 13
Sensitization effect
Response
Trials
Sensitization
In general Sensitization effects can be influenced by
similar parameters as habituation.
However, generalization is greater in Sensitization.
- Following exposure to cutaneous pain, rats’ reactivity to a wide
range of auditory stimuli is increased.
Sensitization can be thought of as “arousal”.
Sensitization “arousal” effect
Sensitization Movie
Habituation and Sensitization in Aplysia
Sensitization Pathway
Increased
serotonin release
Dual-Process theory of
Habituation and Sensitization
2 underlying processes exist
– 1) A Habituation process
– 2) A Sensitization process
The observable behavior is the sum of these two
processes.
The habituation effect is observed when the
habituation process is greater than the
sensitization process.
Dual Process examples
Sensitization effect
Habituation effect
S
S
+
+
NET
-
-
H
NET
H
Trials
Trials
Groves and Thompson (1970)
S-R System: Habituation is thought to occur in the
reflex arc.
State System: Sensitization is thought to occur in
the part of the nervous system that determines
general responsiveness.
Infant attention
Looking
Time
Trials
Emotional responses
Opponent Process Theory of Motivation
Changes in complex emotional responses
Explains:
Drug addiction – tolerance and withdrawal
(?) Marriage – boredom and bereavement