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NEUROBIOLOGY OF THE STRUCTURE OF PERSONALITY: DOPAMINE, FACILITATION OF INCENTIVE MOTIVATION, AND EXTRAVERSION

Depue , Richard A. and Collins , Paul F. NEUROBIOLOGY OF THE STRUCTURE OF PERSONALITY: DOPAMINE, FACILITATION OF INCENTIVE MOTIVATION, AND EXTRAVERSION.

Short Abstract:

Extraversion has two central characteristics: 1) Interpersonal engagement consisting of affiliation (enjoying and valuing close interpersonal bonds, being warm and affectionate)and agency (being socially dominant and enjoying leadership roles, being assertive, exhibitionistic and having a sense of potency in accomplishing goals) and 2) Impulsivity, which emerges from the interaction of extraversion and a second, independent trait (constraint). Agency is a more general motivational disposition including dominance, ambition, mastery, efficacy, and achievement. Positive affect (a combination of positive feelings and motivation) is closely associated with extraversion. Extraversion is accordingly based on positive incentive motivation. Parallels between extraversion (particularly its agency component) and a mammalian approach system based on positive incentive motivation implicate a neuroanatomical network, and is neurotransmitter in the processing of incentive motivation. A corticolimbic-striatal-thalamic network (a) integrates the salient incentive context in the medial orbital cortex, amygdala, and hippocampus; (b) encodes the intensity of incentive stimuli in a motive circuit composed of the nucleus accumbens, ventral pallidum, and ventral tegmental area dopamine projection system; and (c) creates an incentive motivational state that can be transmitted to the motor system. Individual differences in the functioning of this network arise from functional variation in the properties of the ventral tegmental area dopamine projections, which are directly involved in coding the intensity of incentive motivation. Animal evidence suggests that there are three neurodevelopmental sources of individual differences in dopamine: genetic, "experience-expectant", and "experience-dependent processes". Individual differences promote variation in the heterosynaptic plasticity that enhances the connection between incentive context and incentive motivation and behavior. Our psychobiological threshold model explains the effects of individual differences in dopamine transmission on behavior and their relation to personality traits.

Long Abstract:

Extraversion has two central characteristics: 1) Interpersonal engagement consisting of affiliation (enjoying and valuing close interpersonal bonds, being warm and affectionate)and agency (being socially dominant and enjoying leadership roles, being assertive, exhibitionistic and having a sense of potency in accomplishing goals) and 2) Impulsivity, which emerges from the interaction of extraversion and a second, independent trait (constraint). Agency is a more general motivational disposition including dominance, ambition, mastery, efficacy, and achievement. Positive affect (a combination of positive feelings and motivation) is closely associated with extraversion. Extraversion is accordingly based on positive incentive motivation. Parallels between extraversion (particularly its agency component) and a mammalian approach system based on positive incentive motivation implicate a neuroanatomical network, and is neurotransmitter in the processing of incentive motivation. A corticolimbic-striatal-thalamic network (a) integrates the salient incentive context in the medial orbital cortex, amygdala, and hippocampus; (b) encodes the intensity of incentive stimuli in a motive circuit composed of the nucleus accumbens, ventral pallidum, and ventral tegmental area dopamine projection system; and (c) creates an incentive motivational state that can be transmitted to the motor system. Individual differences in the functioning of this network arise from functional variation in the properties of the ventral tegmental area dopamine projections, which are directly involved in coding the intensity of incentive motivation. Animal evidence suggests that there are three neurodevelopmental sources of individual differences in dopamine: genetic, "experience-expectant", and "experience-dependent processes". Individual differences promote variation in the heterosynaptic plasticity that enhances the connection between incentive context and incentive motivation and behavior. Our psychobiological threshold model explains the effects of individual differences in dopamine transmission on behavior and their relation to personality traits.

Keywords:	personality, extraversion, dopamine, incentive motivation, neurobiology, behavioral sensitization, heterosynaptic plasticity
Subjects:	Psychology: Behavioral Analysis Biology: Behavioral Genetics Neuroscience: Neuroendocrinology Neuroscience: Neuropharmacology
ID code:	bbs00000451
Deposited by:	R A Depue on 01 May 2001