Study: Too Little Sleep Almost as Bad as No Sleep

Here’s some news for those who think they can get by on three or four hours of sleep a night for several nights in a row: You may as well be getting no sleep at all.  That’s according to a new study from the University of Wisconsin-Madison School of Medicine and Public Health.

The study appears in the current online edition of the Proceedings of the National Academy of Sciences, and adds to the growing evidence scientists are accumulating about the negative effects of restricted sleep for both the brain and the body.

Researchers kept rats awake 20 hours a day over five days while continuously recording the animals’ brain waves with a sophisticated EEG as they were asleep and awake. The EEGs measured slow wave activity (SWA), the best marker of an individual’s need to sleep as well as the intensity of sleep that follows a period of wakefulness.

“Slow-wave activity reflects the fact that sleep is regulated by homeostasis: in general, the longer we stay awake, the higher is SWA in the subsequent sleep,” said lead researcher Dr. Chiara Cirelli. “We knew that this was true after acute total sleep deprivation (for instance when we stay up all night); now we found that this is also true after chronic sleep restriction.” ”

Knowing that sleep restriction evokes the same brain response as sleep deprivation will help scientists better understand the harmful effects of sleep disturbances, says Cirelli.

“Scientists have learned much from 40 years of studies on total sleep deprivation, she says. “Now we know we can apply the lessons we learned from acute sleep deprivation to chronic sleep restriction, which is very relevant to people’s lives today.”

Source: UW-M News Release