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 BehaviorReflex - 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.

Elicited by complex array or sequence of stimuli.

Elicitation can depend on motivation (“action-specific energy”)

Evolutionarily important behaviors, “instinctive”

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

http://www.indianchild.com/baby_animals.htm

Stephen Jay Gould on the evolution of Mickey Mouse

Supernormal stimulusAn 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

Sensitization effect

Increased response with repeated stimulation.

Elicited behavior is not plastic, but can change with repeated stimulation.

Habituation effect

Decreased response with repeated stimulation.

Habituation effect

Trials

Response

Habituation movie

Rat hears a series of loud bursts of noise

Dishabituation

Dishabituation effect

Trials

Response

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

Trials

Response

Retention Interval

Location of habituation processes

Sensoryadaptation

Fatigue

Habituation

• Sometimes the habituated response will not recover after for a long time. (Long Term Habituation)

Responsesto

Stimulus

Repeated Trialsof stim

Day 1Day 1

Repeated Trialsof stim A

Day 21Day 21

How is habituation different from sensory

adaptation and fatigue?

• Habituation will be slower for stimuli which have a higher salience (i.e., intensity)

Responsesto

Stimulus

Repeated Trials

Resp to weakcoffee flavorResp to weakcoffee flavor

Repeated Trials

Resp to Strongcoffee flavorResp to Strongcoffee flavor

• Dishabituation following the presentation of a novel stimulus.

Responsesto

Stimulus

Repeated Trials

Response tostimulus A(tone)

Response tostimulus A(tone)

PresentStimulus B(light)

PresentStimulus B(light)

Response tostimulus A(tone)

Response tostimulus A(tone)

• Generalization gradient of a habituated response.

Responsesto

Stimulus

Tone frequency of test stimulus followinghabituation at 2000 Hz

2000 2100 2200 2300190018001700

Short-Term v. Long-Term Habituation

Leaton (1976)

Days 1 - 11 Day 12 Day 13

Sensitization effect

Trials

Response

SensitizationIn general Sensitization effects can be influenced by

similar parameters as habituation.

Sensitization can be thought of as “arousal”.

However, generalization is greater in Sensitization.- Following exposure to cutaneous pain, rats’ reactivity to a wide

range of auditory stimuli is increased.

Sensitization “arousal” effect

Sensitization Movie

Habituation and Sensitization in Aplysia

Sensitization Pathway

Increased serotonin release

2 underlying processes exist– 1) A Habituation process

– 2) A Sensitization process

Dual-Process theory ofHabituation and Sensitization

The habituation effect is observed when the

habituation process is greater than the sensitization process.

The observable behavior is the sum of these two processes.

Dual Process examples

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Trials Trials

Habituation effect Sensitization effect

Groves and Thompson (1970)

S-R System: Habituation is thought to occur in thereflex arc.

State System: Sensitization is thought to occur in the part of the nervous system that determines general responsiveness.

Infant attention

Trials

LookingTime

Emotional responses

Opponent Process Theory of Motivation

Changes in complex emotional responses

Explains:

Drug addiction – tolerance and withdrawal

(?) Marriage – boredom and bereavement