PRELIMINARY CONFIRMATION OF THE PROPOSED LINK BETWEEN REWARD-DEPENDENCE TRAITS AND NOREPINEPHRINE

The tridimensional theory of personality posits that traits belonging to a personality spectrum called 'reward dependence' are determined in part by the neurotransmitter norepinephrine (NE). We hypothesized tha t urinary levels of the NE metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) would be significantly correlated to the reward dependence scor e on the Tridimensional Personality Questionnaire (TPQ). Twenty-seven never psychiatrically ill subjects collected urine for MHPG measuremen ts and completed the TPQ. There was a significant correlation between the reward dependence score and the level of MHPG. MHPG level was not associated with the other two personality dimensions, novelty seeking and harm avoidance. This preliminary study supports the hypothesis tha t reward-dependence traits are in part determined by NE.