Traditionally linked to motor control and motivation, the basal ganglia, particularly the nucleus accumbens (NAc), are now recognized as central to sleep–wake regulation. Rodent studies highlight the NAc as a hub where motivation, arousal, and sleep homeostasis converge, mediated by D1- and D2-MSN activity. This review examines its organization and circuits, emphasizing roles in vigilance, valence, and associative learning, and exploring emerging hypotheses on its contribution to sleep-related cognition and disorders.
