Novelty Seeking but not BAS is associated with high dopamine as indicated by a neurotransmitter challenge test using mazindol as a challenge substance

The dopaminergic system is linked to many aspects of normal and pathological behavior. Major theories of personality hypothesize variation in dopaminergic activity to underlie traits such as novelty seeking or extraversion. In Gray's (1973) theory of personality the behavioral approach system (BAS) is also linked to dopaminergic activity and conceptually closely related to impulsivity, extraversion, and novelty seeking. The aim of this study is to examine the biological basis of the BAS with respect to dopamine by use of the BIS/BAS- and Novelty Seeking scales. Using a neuroendocrine challenge paradigm, mazindol, a selective dopamine reuptake inhibitor, was applied to 50 participants in a balanced randomized placebo-controlled crossover design. Prolactin (PRL) responses were compared for two groups of high and low BAS scorers. No significant effects could be found for any of the BAS scales. In contrast, high Novelty Seeking (NS+) was characterized by an overall lower level of prolactin as compared to NS− and showed a blunted PRL response to mazindol as compared to NS−. These results indicate that NS is associated with high levels of dopamine, and that mazindol as a challenge substance is useful to investigate dopaminergic responsivity according to NS. Moreover, they indicate that BAS less clearly relates to the dopaminergic neurotransmitter system. Possible reasons are discussed.