Most people would agree that there’s nothing better than a good night’s sleep. Stressful day at the office? Long hours doing yard work and housework? All this can be repaired with a nice, long slumber.
Thousands of sleep studies have been conducted over the years. However, we still lack a definitive understanding of why we sleep.
Before 1951, scientists thought bedtime was merely a shutdown mode for both the body and mind. It wasn’t until a graduate student at the University of Chicago hooked his son up to a brain wave machine during sleep that we learned about rapid eye movement (REM) sleep periods, when the brain speeds up its activity. During REM sleep, our eyes twitch, our limbs and facial muscles may twitch, and we experience vivid dreams.
One sleep theory is that our brain reviews the information it received that day and decides what should be retained and where it should be stored. Behavioural research supports this notion, but sleep is so complex and individualised for each person that it’s challenging to obtain conclusive results.
Although we aren’t exactly sure why we sleep, we know that we have to – all mammals do. In fact, a lab rat that would normally live for three years will die in about three weeks without sleep.
Originally published in the December 2009 issue of estidotmy.