Lesson 1: Clinical Disorders – Part D

PART D

Functions of Sleep

Animal studies have demonstrated that sleep is essential for survival. Laboratory rats will normally live for two to three years; rats deprived of REM sleep survive an average of only five months. Rats deprived of all sleep survive only about three weeks. In humans, extreme sleep deprivation can cause an apparent state of paranoia and hallucinations in otherwise healthy individuals. However, despite identifying several physiological changes that occur in the brain and body during sleep, scientists still do not fully understand the functions of sleep.

Sleep also allows the brain to be cleansed by cerebral spinal fluid.  Since we do not have lymph vessels in the brain to remove waste, the brain has a unique way of cleansing itself when we sleep.  Please watch the video below.

Video:  One more reason to get a good night's sleep

 Benefits of Sleep

Athletics - There is a link between insufficient sleep and reaction time.  A lack of sleep can lead to completely missed cues (eg.  you don't see the pitcher releasing the baseball) and a slowed reaction time (you see the pitch but react too slowly.  A study published in 2011 looked at the Stanford men's varsity basketball team.  The students were told to get as much sleep as possible.  They had no trouble complying and got an average of 111 minutes of extra sleep.  After two to four weeks of this, they were not only better athletes, they were happier.  The subjects also reported improved overall ratings of physical and mental well-being during practices and games.  A similar study involving swimmers found more sleep time brought faster times in the pool.  Athletes from all sports can benefit from extra sleep time in order to get the additional competitive edge to perform at their highest level.

Learning - Although we gather information while we are awake, we learn it while we are sleeping. The brain restores the synapses, taking the information worth keeping and learning it. The brain also flushes out the useless information that we do not use.

Healthy Bodies - There is a link between lack of sleep and weight gain.  Fat is not metabolized very well at night, resulting in lipid levels and blood glucose.  The body does not process and store nutrients at night as it does during the day.  Skin can suffer too.  You look better after a good nights sleep.  Studies also link lack of sleep and illness in teens.  Males in particular are more likely to get a cold when they lack sleep.

Improves mental outlook:  Depression and sleep issues have been linked in many studies, including a 2008 report that tied sleep disturbances to suicide in teens.

Reference:  Gabriella Boston, The Washington Post