Understanding Importance of Sleep
What is Sleep? Sleep is an important part of our daily routine, you spend one third of your day asleep. Without sleep we cannot form or maintain the pathways to our brains that let us learn and create new memories and you may find it harder to concentrate and respond and react quickly. Sleep is important for a number of brain functions, including how nerve cells communicate with each other. Sleep affects almost every type of tissue and system in the body-from the brain, heart, and lungs to metabolism, immune function, mood and disease resistance.
In this modern day and age with it’s technological advances, we find that we are getting less sleep now than ever. A study done in 2013 showed that the average American sleeps 6.8 hours a night with 40% sleeping less than 6 hours a night. Comparing this to a study done by the same research group in 1942, The typical American average 7.9 hours of sleep a night with only 11% sleeping less than 6 hours a night. Going further back to 1910, the average american sleeps just over 9 hours a night. Let us delve deeper into the topic of sleep by first understanding what is sleep?
Sleep has the following characteristics which in many ways define sleep:
- Sleep is a period of reduced activity
- Sleep is associated with a typical posture, such as lying down with eyes closed (for humans)
- Sleep results in a decreased responsiveness to external stimuli
- Sleep is a state that is relatively easy to reverse
There are two basic types of sleep, rapid eye movement (REM) and non-REM sleep (which has three different stages):
- Stage 1 (N1): non-REM sleep is the changeover from wakefulness to sleep.
- Stage 2 (N2): a period of light sleep before you enter deep sleep.
- Stage 3 (N3): the period of deep sleep that you need to feel refreshed in the morning. It occurs in longer periods during the first half of the night.
Each sleep cycle contains five distinct phases, which exhibit different brain wave patterns. It suffices to say that one sleep cycle lasts an average of 90 minutes: about 65 minutes of normal/non-REM sleep, 20 minutes of REM sleep and a final 5 minutes of non-REM sleep. REM or deep sleep makes up 20-25% of your sleep each night.