Brain needs quality sleep

BACK

New research has found that many sleepless nights - that is, fewer than six hours of shut eye a night - can impair one's mental performance as much as staying awake for two nights in a row.

Many people think that their bodies get used to functioning on minimal sleep without any consequences. But a new study carried out by researchers at the University of Pennsylvania School of Medicine in Philadelphia, has found that this is not the case.

Two weeks of sleep deprivation During the study that was headed up by Dr Hans van Dongen, 48 participants were divided into four groups. For two weeks the first group were allowed four hours of sleep a night, the second group got six hours, the third group got eight hours and the fourth group had no sleep for three days.

The study was published in the March issue of the journal Sleep.

Researchers monitored the groups in a laboratory for the full two weeks to ensure that they did not fall asleep or drink coffee. Each day, all the participants were periodically put through a number of mental and psychological tests and were asked to evaluate how tired they felt.

Little sleep is as bad as no sleep The research team found that people sleeping less than eight hours a night has slower reaction times and were less able to think clearly and carry out simple memory tasks. They also did as badly on certain tasks as the participants who hadn't slept at all for one or two nights.

When individuals did get some sleep, they felt less tired than the participants who went without any sleep, despite test results that indicated that they were just as impaired mentally.

Implications for night workers The implications of this study are that the employers of people like soldiers, trainee doctors, shift workers and anyone else who's job results in them being chronically sleep-deprived, should take countermeasures to look after their mental health.

Van Dongen suggests that the working hours that people in these stressful professions should be limited. They should also have a chance to nap at "strategic times" or, in order to remain alert, they should be allowed to use chemical stimulants such as caffeine. Getting enough sleep is a lifestyle decision. The study is very interesting because it shows what happens to the body when it is left to deal with a lack of sleep without the help of chemical stimulants or other distractions.

The study also found that number of hours of shuteye that a body needs varies greatly from person to person. Therefore researchers say that getting enough sleep is a personal "life-style decision" which each person needs to control individually.