Sleep and synaptic changes.

Several recent studies, using molecular, electrophysiological, or structural approaches, have investigated how synapses are affected by sleep, spontaneous wake, chronic sleep restriction, and acute sleep deprivation. Overall, the results have found that even a few hours of sleep or wake can modify the molecular composition of excitatory synapses, change their efficacy, and make synapses grow or shrink. Moreover, partial and total loss of sleep affect the ability of synapses to undergo long-term potentiation, an effect that may underlie some of the negative consequences of sleep deprivation on memory and other cognitive functions.