Topic: dorsal raphe nucleus (DRN)

Serotonin (5-HT) is an essential neuromodulator affecting behavioral, affective, and cognitive functions. Recent studies by tryptophan depletion in humans and devaluation paradigm in mice suggest that 5-HT promotes model-based decision making. However, the influence of 5-HT on such decision making remains poorly understood. Recent development of rodent two-step decision making tasks enables us to examine the effect of 5-HT manipulations in situations where rewards do not simply reinforce previous choices but rather interact with task structure to influence policy. Here we took a two-step decis