The relation between dopamine D-2 receptor density and personality: Preliminary evidence from the NEO personality inventory-revised

Objective: To examine the relation between dopamine (DA) D-2 receptor-speci fic binding and personality, we assessed the relation between DA D-2 bindin g and the NEO Personality Inventory Revised (NEO PI-R). Background: Previou s studies have demonstrated a relation between DA D-2 receptor-specific bin ding and a personality trait involving personal detachment as defined by th e Karolinska Scales of Personality. A subsequent study using a different me asure of personal detachment failed to replicate this finding, suggesting t hat metric properties of the personality scale may be important. To further examine this issue, we assessed the relation between DA D-2 binding and a third personality measure, the NEO PI-R. Methods: Eighteen adult subjects c ompleted the NEO PI-R and participated in an C-11-raclopride positron emiss ion tomography study to quantify striatal DA D-2 receptor binding. Results: We did not find a significant relation between binding and detachment-like traits on the NEO PI-R; however, we found a significant relation between D A D-2 receptor binding and the NEO PI-R personality facet of Depression (r = 0.75, p <0.0001). Conclusions: The results fail to replicate the findings of previous studies reporting an association between DA D-2 receptor densi ty and personal detachment, suggesting that the relation is relatively spec ific to the trait defined by the Karolinska Scales of Personality. The rela tion between a nonclinical personality trait of depression and DA D-2 bindi ng, if replicated, may help to elucidate the role of dopamine in depression .