Modulation of impulsivity and reward sensitivity in intertemporal choice by striatal and midbrain dopamine synthesis in healthy adults.

ABSTRACT: Converging evidence links individual differences in mesolimbic and mesocortical dopamine (DA) to variation in the tendency to choose immediate rewards ("Now") over larger, delayed rewards ("Later"), or "Now bias." However, to date, no study of healthy young adults has evaluated the relationship between Now bias and DA with positron emission tomography (PET). Sixteen healthy adults (ages 24-34 yr; 50% women) completed a delay-discounting task that quantified aspects of intertemporal reward choice, including Now bias and reward magnitude sensitivity. Participants also underwent PET scanning with 6-[(18)F]fluoro-l-m-tyrosine (FMT), a radiotracer that measures DA synthesis capacity. Lower putamen FMT signal predicted elevated Now bias, a more rapidly declining discount rate with increasing del

SUBMITTER: Smith CT 

PROVIDER: S-EPMC4808128 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature