5 Stages of Sleep
Medical practitioners around the world have come to realize just how important sleep is, for our overall physical and mental well-being.
Learning about the body’s stages of sleep can help some individuals understand their own circadian rhythms better as well as making appropriate changes to their sleep habits, allowing for the optimal amount of sleep cycles each night.
Stage One:
Within minutes (sometimes even within seconds!) of falling asleep, your brain produces what are called alpha and theta waves in addition to your eye movements slow down.
This introduction to sleep is relatively brief, lasting up to seven minutes. Here, you are in light stage of sleep, which means that you're somewhat alert and can be easily woken.
Stage Two:
During this stage, which is also fairly light, the brain produces sudden increases in brain wave frequency known as sleep spindles. Then brain waves slow down.
If you were to schedule a “power nap” you’d want to wake up after this stage of sleep.
Stages Three:
This stage is the beginning of deep sleep, as the brain begins producing slower delta waves. You won't experience any eye movement or muscle activity.
At this point, it becomes a little harder for you to be awakened, because your body becomes less responsive to outside stimuli.
Stage Four:
The brain produces even more delta waves and you move into an even deeper, more restorative stage of sleep. It's most difficult to wake up during this stage.
This is when the body repairs muscles and tissues, stimulates growth and development, boosts immune function, and builds up energy for the next day.
Rapid Eye Movement (REM) Sleep:
You generally enter REM sleep about 90 minutes after falling asleep and each REM stage can last up to an hour. An average adult has five to six REM cycles each night.
During this final phase of sleep, your brain becomes more active. This is when most dreaming occurs, your eyes jerk quickly in different directions (hence, the name!), heart rate and blood pressure increase, breathing becomes fast, irregular, and shallow.
REM sleep plays an important role in learning and memory function, since this is when your brain consolidates and processes information from the day before so that it can be stored in your long-term memory.
Please note!
That these phases last for different durations at various ages; an infant’s sleep cycle will look different than that of an adult or elderly individual.