Neurobiology of the structure of personality: Dopamine, facilitation of incentive motivation, and extraversion

Abstract

Extraversion has two central characteristics: (1) interpersonal engagement, which consists of affiliation (enjoying and valuing close interpersonal bonds, being warm and affectionate) and agency (being socially dominant, enjoying leadership roles, being assertive, being 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 that includes 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 behavioral approach system based on positive incentive motivation implicate a neuroanatomical network and modulatory neurotransmitters in the processing of incentive motivation. A corticolimbic-striatal-thalamic network (1) integrates the salient incentive context in the medial orbital cortex, amygdala, and hippocampus; (2) 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 (3) 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 ventral tegmental area dopamine projections, which are directly involved in coding the intensity of incentive motivation. The animal evidence suggests that there are three neurodevelopmental sources of individual differences in dopamine: genetic, “experience-expectant,” and “experience-dependent.” Individual differences in dopamine 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 is discussed.

Influence of fluoxetine on positive and negative affect in a clinic-based smoking cessation trial

“…Animal models of brain reward function are relevant to understanding positive mood effects in humans to the extent that positive emotions can be viewed as subjective cues that motivate approach behavior toward rewards (Depue and Collins 1999). Findings from animal studies indicate that fluoxetine heightens responsivity to rewards, and suggest dopaminergic (DA) and serotonergic (5-HT) mechanisms of action.…”

“…reverses diminished responding to rewarding stimuli; Harrison et al 2001). To the extent that diminished positive affect is associated with diminished reinforcing value of approach behavior to rewards (Depue and Collins 1999), fluoxetine might buffer the losses in positive affect associated with quitting smoking.…”

Anger is an approach-related affect: Evidence and implications.

“…The idea that approach and avoidance systems have partially distinct neural substrates is also quite prominent today, in varying forms (e.g., Cloninger, 1987;Davidson, 1998;Depue & Collins, 1999;Fowles, 1980;Gray, 1994aGray, , 1994bPizzagalli, Sherwood, Henriques, & Davidson, 2005).…”

Behavioural Stimulation and Sensation-Seeking among prisoners: Applications to substance dependency

“…Specifically, impulsivity was distinct from sensationseeking, thus failing to support any suggestion that impulsivity was intrinsically related to this concept (e.g. Acton, 2003;Depue & Collins, 1999;Kelly et al, 2006;Moeller et al 2002;Sher & Trull, 1994;Zuckerman et al, 1993) and/or was an adult-form of sensation-seeking (Clayton, Segress & Caudill, 2007). Thus, in samples where there are known to be increased levels of sensation-seeking and impulsivity (e.g.…”

“…It is closely related to other personality constructs associated with substance use, such as impulsivity (e.g. Acton, 2003;;Ersche, et al, 2010;Moeller et al 2002), openness to experience and extraversion (Grekin, Sher & Wood, 2006), with considerable cross-over across these constructs (Depue & Collins, 1999;Kelly et al, 2006;Sher & Trull, 1994;Zuckerman et al, 1993). For example, some researchers have suggested that extraversion is an indirect test of sensation-seeking (Sher & Trull, 1994), with impulsivity a reconceptualised 'adult' form of sensation-seeking (Clayton, Segress & Caudill, 2007).…”