Circadian rhythms and memory formation

Circadian cycling of biological processes is widely conserved across phylogeny. Gerstner and Yin discuss how regulators of circadian rhythms — including clock genes, melatonin and the suprachiasmatic nucleus — affect synaptic plasticity and memory formation. There has been considerable progress in elucidating the molecular mechanisms that contribute to memory formation and the generation of circadian rhythms. However, it is not well understood how these two processes interact to generate long-term memory. Recent studies in both vertebrate and invertebrate models have shown time-of-day effects on neurophysiology and memory formation, and have revealed a possible role for cycling molecules in memory persistence. Together, these studies suggest that common mechanisms underlie circadian rhythmicity and long-term memory formation.