Circadian Rhythm Disruption and Neurobehavioral Function: Roles of Melatonin, Spatial Memory, Motor Coordination and Feeding Behavior

Circadian rhythms coordinate sleep–wake behavior, endocrine secretion, metabolism and neural function across the approximately 24-hour day. Disruption of the circadian system can alter cognitive performance, motor behavior, feeding patterns and melatonin secretion, although the direction and magnitude of these effects depend on species, lighting conditions, disease model and experimental protocol. This narrative review examines the molecular organization of the mammalian circadian clock, the role of the suprachiasmatic nucleus and peripheral oscillators, and mechanistic links between circadian misalignment and neurobehavioral outcomes. Particular attention is given to the Morris water maze as an assay of spatial learning, the rotarod as an assessment of motor coordination, time-dependent melatonin measurements and food-intake monitoring in rodents. Methodological considerations—including Zeitgeber-time reporting, repeated testing, motor confounding, cage-level food measurements and melatonin assay validation—are discussed. The review concludes that multimodal behavioral, endocrine and metabolic assessments can provide complementary information, but robust inferences about circadian phase or rhythm disruption require repeated sampling across the circadian cycle and appropriate experimental controls.