Every 60-100 minutes we go through about five cycles of five stages of sleep every night
A drowsy, relaxed state between being awake and sleeping - breathing slows, muscles relax, heart rate drops, usually lasts up to seven minutes. This stage is of sleep is often associated with the term ‘catnaps’.
Still a fairly slight sleep – the brain produces sudden increases in brain wave frequency known as sleep spindles – then the brain waves slow down. If a ‘power nap’ is taken now you would want to wake up after this stage of sleep.
Stage 3 and Stage 4
This is the beginning of deep sleep, the brain begins to produce slower delta waves. It would become harder to be awakened from these stages, as your body becomes less responsive to external stimulus. The brain produces further delta waves and you move further into deep sleep which leads to a restorative stage of sleep – this is the most difficult stage to wake from. Your body repairs muscles and tissues, stimulates growth and development, boosts immune function and builds up energy for the following day.
Rapid Eye Movement (REM) Sleep
After about 90 minutes from when you fall asleep, you move into REM sleep which can last about an hour. With the brain becoming more active this stage is aptly named, due to the eyes moving in different directions and commonly known as dream sleep.
The REM stage of sleep is important in learning and memory function, your brain stores and processes information from the day so it can be filed away in long-term memory.