We appreciate sleep when we can’t get it. Luckily the days of 36 hour residency shifts are done! Most people don’t do well with less than seven hours of sleep daily. And prolonged sleep deprivation causes multiple health ill effects. There is variation in how much sleep everyone needs, and let us start with understanding of the structure of the sleep cycle and the benefits of sleep.

Through the night, we cycle multiple times through two broad categories of sleep, Non-REM and REM sleep. We start with a drowsy phase and start sleep with a light N1 non REM sleep, progressing through N2 and N3, the deep sleep cycle. This is followed by the Rapid Eye Movement, or REM sleep. Each cycle lasts for 90-120 minutes and the percentage of REM sleep increases with each sleep cycle.

Sleep is necessary for memory and cognitive function, repairing brain circuits and restoring the body with protein sythesis and tissue repair. We also clean out the stores of adenosine that accumulate in the brain in the waking hours. Adenosine causes fatigue and sleep cleans it out.

Do refer to my YouTube video on the sleep cycle and we will further delve into issues with sleep in future posts.

https://www.youtube.com/watch?v=iAKCGrAMr5k&feature=youtu.be