A neural circuit for male sexual behavior and reward

Male sexual behavior is innate and rewarding. Despite its centrality to reproduction, a molecularly specified neural circuit governing innate male sexual behavior and reward remains to be characterized. We have discovered a developmentally wired neural circuit necessary and sufficient for male mating. This circuit connects chemosensory input to BNSTpr^Tac1 neurons, which innervate POA^Tacr1 neurons that project to centers regulating motor output and reward. Epistasis studies demonstrate that BNSTpr^Tac1 neurons are upstream of POA^Tacr1 neurons, and BNSTpr^Tac1-released substance P following mate recognition potentiates activation of POA^Tacr1 neurons through Tacr1 to initiate mating. Experimental activation of POA^Tacr1 neurons triggers mating, even in sexually satiated males, and it is rewarding, eliciting dopamine release and self-stimulation of these cells. Together, we have uncovered a neural circuit that governs the key aspects of innate male sexual behavior: motor displays, drive, and reward.