As you go to sleep at night your body is resting, however your brain is constantly at work manufacturing various molecules in the form of proteins, steroids, cholesterol, lipid rafts, human growth hormone and more.
The reason why we sleep is because it gives the brain the opportunity make sense of your experiences and consolidate memories, and in some ways reset itself in preparation for the next day. As such, sleep plays a critical role in the brain’s development.
Sleep is also important for restorative purposes. It provides an opportunity for the body to repair and rejuvenate itself. Studies have actually shown that when we’re deprived of sleep it weakens the immune system and therefore makes the body more susceptible to disease. Moreover, many of the major restorative functions within the body such as muscle growth and tissue repair occur mostly during stages of sleep.
There are five recognized stages of sleep. Here is a quick summary of each stage:
- Stage 1: Is the realm of alpha waves where we enter a daydream-like state. You are not yet asleep but rather in a deep state of relaxation or trance state.
- Stage 2: Is the realm of theta waves. This stage of sleep lasts about 20 minutes as body temperature begins to drop and heart rate starts to slow down.
- Stage 3: Is the beginning of the delta wave phase of sleep. This stage is a transition period between light and a deep sleep.
- Stage 4: Delta waves dominate this stage of sleep. This is a deep state that lasts about 30 minutes. This is where your immune system is strengthened and your body begins to undergo repair.
- Stage 5: Is the realm of REM sleep. This stage of the sleep is characterized by rapid eye movement, increased respiration and brain activity. It is the stage of sleep where you dream. Interestingly though your muscles relax and your body enters a state of paralysis. This is designed as a protective mechanism to prevent you from hurting yourself. REM sleep is actually also a restorative part of the sleep cycle. Some studies have even suggested that REM sleep helps your brain to process the day’s experiences.
Read more: Getting a Better Night’s Sleep