Sleep in early life may play crucial role in brain d...( sleep and we also known that these neu...)

In either case, the new evidence that sleep appears to play a significant role in brain development puts researchers an important step closer to solving a mystery that has persisted for decades. "Every animal sleeps - even flies may have a state like sleep. But despite great progress in our understanding of the regulation and neurobiology of sleep, as well as the consequences of sleep loss on human performance, why the brain needs sleep has remained a mystery," says Frank.

"Speculation has ranged from evolutionary theories - we need sleep to prevent us from wandering out of our caves in the dark or sleep is just a way of keeping us inactive for period of time when goblins or saber tooth tigers are out - to theories having to do with the function of neural networks," says Stryker.

Researchers have known that in early development birds and mammals, including humans, sleep as much as three times the amount as adult birds and mammals. And they have long suspected that neuronal connections are remodeled during sleep. Previous studies in humans have shown that sleep and sleep loss influence learning and memory - two processes thought to depend on neuronal plasticity. And studies have shown that animals and humans deprived of sleep do not perform well on memory tasks. Other studies in rodents, birds and humans have suggested that neuronal activity initiated while awake is reactivated and possibly consolidated during subsequent sleep.

Other studies have shown that sleep and sleep loss modify the expression of several genes and gene products that may be important for synaptic plasticity; that certain forms of long-term potentiation, a neural process associated with the laying down of learning and memory, can be elicited in sleep, sugg
'"/>

Contact: Jennifer O'Brien
jobrien@pubaff.ucsf.edu
415-476-8432
University of California - San Francisco
25-Apr-2001