Circadian Rhythms and Memory: Exploring the Mechanisms of Synaptic Plasticity, Hormonal Modulation, and Cognitive Function

Circadian rhythms influence memory formation, consolidation, and retrieval. The suprachiasmatic nucleus coordinates the internal circadian timing with external environmental signals, serve as the central pacemaker. This alignment influences the timing and efficiency of synaptic plasticity across various brain regions, particularly the hippocampus. Normal circadian regulation affects hippocampus-dependent processes such as long-term depression and long-term potentiation, contributing to time-of-day variations in memory consolidation. These activities are governed by core clock genes, which interact with signaling pathways like the cAMP-MAPK-CREB cascade. Additionally, circadian rhythms are modulated by hormones such as cortisol and melatonin, which help regulate sleep cycles and memory processing. Sleep deprivation or disruptions in circadian rhythms, like irregular light exposure, can impair cognitive function and hinder memory performance. Understanding the mechanisms linking circadian rhythms and memory could provide new treatment approaches for memory dysfunctions associated with disrupted circadian control.