Tuesday, March 13, 2007

The Importance of a Good Night's Sleep

The older I get (I just turned 37) the more I have come to value a good night's sleep. No doubt this is linked to the fact that parenthood makes such a sleep more of a rarity than it once was.

This article in Nature Neuroscience suggests that a good sleep is important for forming new memories. Here is the abstract:

"A deficit in the ability to form new human memories without sleep"
Nature Neuroscience - 10, 385 - 392 (2007)
Seung-Schik Yoo1, Peter T Hu, Ninad Gujar, Ferenc A Jolesz & Matthew P Walker

Evidence indicates that sleep after learning is critical for the subsequent consolidation of human memory. Whether sleep before learning is equally essential for the initial formation of new memories, however, remains an open question. We report that a single night of sleep deprivation produces a significant deficit in hippocampal activity during episodic memory encoding, resulting in worse subsequent retention. Furthermore, these hippocampal impairments instantiate a different pattern of functional connectivity in basic alertness networks of the brainstem and thalamus. We also find that unique prefrontal regions predict the success of encoding for sleep-deprived individuals relative to those who have slept normally. These results demonstrate that an absence of prior sleep substantially compromises the neural and behavioral capacity for committing new experiences to memory. It therefore appears that sleep before learning is critical in preparing the human brain for next-day memory formation—a worrying finding considering society's increasing erosion of sleep time.