Individual differences in successful self-regulation of the dopaminergic midbrain

Abstract The dopaminergic midbrain is associated with reinforcement learning, motivation and decision-making – functions often disturbed in neuropsychiatric disorders. Previous research has shown that dopaminergic midbrain activity can be endogenously modulated via neurofeedback. However, the robustness of endogenous modulation, a requirement for clinical translation, is unclear. Here, we examined whether the activation of particular brain regions associates with successful regulation transfer when feedback is no longer available. Moreover, to elucidate mechanisms underlying effective self-regulation, we studied the relation of successful transfer with temporal difference coding outside the midbrain during neurofeedback training and with individual reward sensitivity in an monetary incentive delay (MID) task. Fifty-nine participants underwent neurofeedback training either in standard (Study 1 N=15, Study 2 N=28) or control feedback group (Study 1, N=16). Successful self-regulation was associated with prefrontal reward sensitivity in the MID task (N=25), with a decreasing relation between prefrontal activity and midbrain learning signals during neurofeedback training and with increased activity within cognitive control areas during transfer. The association between midbrain self-regulation and prefrontal temporal difference and reward sensitivity suggests that reinforcement learning contributes to successful self-regulation. Our findings provide new insights in the control of midbrain activity and may facilitate individually tailoring neurofeedback training.