title: Incentive motivation is associated with striatal dopamine asymmetry.
abstract: Dopamine plays an important role in modulating incentive motivation, expressed behaviorally as approach behavior. EEG studies report association between approach behavior and asymmetric pattern of activation in anterior cortical regions (as measured by the inverse of EEG alpha power). Therefore, individual differences in incentive motivation may reflect asymmetries in dopaminergic systems. We examined this hypothesis by studying the relationship between self-reported degree of incentive motivation, and asymmetry of D2 receptor availability in healthy volunteers. Nineteen healthy participants were studied with positron emission tomography (PET) and [11C]raclopride to assess the availability of dopamine D2 receptors in left and right striatum. Incentive motivation was assessed by the Achievement scale of the Multidimensional Personality Questionnaire. The Achievement score was negatively correlated with the Asymmetry Index ([R-L]/[R+L]) of D2 receptor availability (r=-.721, p=.001), suggesting that greater positive incentive motivation is associated with higher receptor availability in the left relative to the right hemisphere.
authors.affiliation: Department of Psychology & Brain and Behavior Center, University of Haifa, Mount Carmel 31905, Israel. rtomer@psy.haifa.ac.il
authors.forename: Rachel
authors.initials: R
authors.lastname: Tomer
authors.forename: Rita Z
authors.initials: RZ
authors.lastname: Goldstein
authors.forename: Gene-Jack
authors.initials: GJ
authors.lastname: Wang
authors.forename: Christopher
authors.initials: C
authors.lastname: Wong
authors.forename: Nora D
authors.initials: ND
authors.lastname: Volkow
mesh_terms: D000328:Adult; D000368:Aged; D004298:Dopamine / Q000502:physiology*; D018492:Dopamine Antagonists; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007206:Individuality; D008297:Male; D008875:Middle Aged; D009042:Motivation; D017072:Neostriatum / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000502:physiology*; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000378:metabolism; D049268:Positron-Emission Tomography; D020891:Raclopride; D017448:Receptors, Dopamine D2 / Q000378:metabolism; D050637:Receptors, Dopamine D3 / Q000378:metabolism; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D018492:Dopamine Antagonists; D050483:Dopamine Plasma Membrane Transport Proteins; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D020891:Raclopride; D004298:Dopamine