Extraversion is a core personality trait associated with individual differences in reward sensitivity and has been linked to the dopaminergic brain system. We investigated whether dopaminergic receptor availability in the striatum was directly associated with individual differences in extraversion using the high-affinity radiotracer [18F]fallypride and PET. Seventeen healthy male and female participants completed an [18F]fallypride PET scan at rest. Extraversion was assessed using the revised Eysenck Personality Questionnaire. Dopamine receptor availability in predefined striatal regions of interest was assessed as [18F]fallypride binding potential using a reference tissue model for [18F]fallypride. Both region of interest and voxel-based whole-brain analyses showed that extraversion was significantly correlated with dopaminergic receptor availability in the striatum bilaterally. This finding contributes to our understanding of the dopaminergic neural mechanisms underlying individual differences in extraversion.
aDepartment of Brain and Cognitive Engineering, Korea University and
bDepartment of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seoul, Korea
Correspondence to Sang Hee Kim, PhD, Department of Brain and Cognitive Engineering, Science Library 604B, Korea University, Anam-dong 5ga, Seongbuk-gu, Seoul 136-713, South Korea Tel: +82 2 3290 5923; fax: +82 2 926 2168; e-mail: email@example.com
Received November 8, 2011
Accepted December 14, 2011