Risk-taking is frequently observed in psychiatric conditions such as attention-deficit hyperactivity disorder, yet the neuronal mechanisms underlying this behavior remain unclear. Here, we show that histamine H(2) receptor (H(2)R) in parvalbumin-positive neurons (PV^(+)) of the substantia nigra pars reticulata (SNr) bidirectionally regulates risk-taking behaviors. Dysfunction of superior colliculus-projecting SNr PV^(+) neurons contributes to the increased risk-taking caused by H(2)R deficiency….
