Topic: cellular engrams

The endogenous circadian rhythm of organisms maintains fundamental physiological processes and behaviour by synchronising them to the external environment. Disturbance to this rhythm in our modern societies, caused by the use of artificial light in dark periods, electronic gadgets, shift work, and poor sleep hygiene negatively impacts physiological and cognitive health. Studies in rodent hippocampus show that neuronal membrane excitability shows a diurnal rhythm and disturbance to the circadian cycle impairs hippocampal plasticity and memory. However, it is not clear how acute circadian distur

The dentate gyrus (DG) plays a key role in memory encoding and retrieval, facilitating discrimination of the environmental inputs by separating them into non-overlapping patterns and reducing interference of stored representations. It is highly susceptible to aging-related structural and physiological changes and thought to contribute to age-related cognitive dysfunctions. In this study we examined possible age-related changes in pattern separation function and associated changes in DG cellular engrams using a contextual fear conditioning task. Young adult (3-month-old) and healthy aged (24-mo