Renormalizing synapses in sleep: The clock is ticking

Sleep has been hypothesized to renormalize synapses potentiated in wakefulness. This is proposed to lead to a net reduction in synaptic strength after sleep in brain areas like the cortex and hippocampus. Biological clocks, however, exert independent effects on these synapses that may explain some of the reported differences after wake and sleep. These include changes in synaptic morphology, molecules and efficacy. In this commentary, I discuss why no firm conclusions should be drawn concerning the role of sleep in synaptic renormalization until the role of circadian rhythms are isolated and determined.

Automated summary

In general, sleep is believed to aid in the renormalization of synapses, but biological clocks also have independent effects on synapses. Therefore, firm conclusions about the role of sleep in synaptic renormalization should not be drawn until the effects of circadian rhythms are isolated and determined.