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. 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
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 stimuli? v.
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 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
Location of habituation processes Sensory adaptation Fatigue Habituation
Sometimes the habituated response will not recover after for a long time. (Long Term Habituation) How is habituation different from sensory adaptation and fatigue?
Habituation will be slower for stimuli which have a higher salience (i.e., intensity)
Dishabituation following the presentation of a novel stimulus.
Generalization gradient of a habituated response.
Short-Term v. Long-Term Habituation Leaton (1976) Days Day 12Day 13
Sensitization effect Trials Response
Sensitization In 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
2 underlying processes exist –1) A Habituation process –2) A Sensitization process Dual-Process theory of Habituation 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 Habituation effect Sensitization effect
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.
Trials Looking Time
Opponent Process Theory of Motivation
Changes in complex emotional responses Explains: Drug addiction – tolerance and withdrawal (?) Marriage – boredom and bereavement