Effects of Sleep Deprivation Are Worse Than Thought

Sleeping for only four hours per night for an entire week had the same effect on the brains of group of volunteers as acute total sleep deprivation. The finding is a new alert signal for people who get only limited hours of sleep each night.

Even short-term exposure to sleep deprivation can have significant consequences on the human brain, the research team learned. The group was based at the University of Wisconsin-Madison (UWM), and was led by Dr Chiara Cirelli.

The new investigation was conducted on unsuspecting lab rats, whose response to such situations is very similar to our own. The data collected shows that the negative consequences of getting only a few hours of sleep per night affect both the mind and the body more than first thought.

“There's a huge amount of interest in sleep restriction in the field today,” explains Dr. Cirelli, who is also an associate professor of psychiatry at the UWM School of Medicine and Public Health. She was the leader of the new research effort, ScienceDaily reports.

Details of the work were published in the current online issue of the esteemed journal Proceedings of the National Academy of Sciences (PNAS). The main conclusion is that people are oftentimes tired because they choose to be so, and not necessarily because they are forced to stay awake.

“Instead of going to bed when they are tired, like they should, people watch TV and want to have an active social life. People count on catching up on their sleep on the weekends, but it may not be enough,” she adds.

Previous researches have demonstrated that so-called “sleep debts” cannot be accounted for with sleeping a few extra hours in the weekend. This concept is generally applied when people calculate the difference between how much hours they slept during week nights, and how much hours they should have slept.

“Even relatively mild sleep restriction for several nights can affect an individual's ability to perform cognitive tasks. Sleep restriction can also increase resistance to insulin, leading to a risk of diabetes,” the team leader says.

“For instance, recent studies in humans have shown that 5 days with only 4 h of sleep/night result in cumulative deficits in vigilance and cognition, and these deficits do not fully recover after one night of sleep, even if 10 hours in bed are allowed,” Dr. Cirelli concludes.