REM and Non-REM Sleep
REM Sleep
- REM, or Rapid Eye Movement, happens in cycles throughout the night and increases in length as the night progresses.
- This stage of sleep is unique due to the fast and random movement of eyes, hence its name.
- Dreams primarily occur during REM sleep.
- The brain is highly active during this stage, with brain wave activity similar to that of being awake.
- REM sleep aids in learning and memory; it plays a key role in brain development.
Non-REM Sleep
- Non-REM sleep is the period of sleep not characterised by rapid eye movements.
- It can be divided into three stages: N1, N2, and N3.
N1
- This is the stage between consciousness and sleep, also known as somnolence or drowsy sleep.
- You may experience sudden muscle contractions known as hypnic jerks.
- Eye movement is slow and muscle activity decreases.
N2
- This is the first stage of true sleep.
- Heart rate slows down and body temperature decreases as the body prepares for deep sleep.
- Eye movement stops during N2, and brain waves become slower.
N3
- Known as deep sleep or slow-wave sleep, you are hardest to wake up during this stage.
- There are extremely slow brain waves, known as delta waves, mixed with smaller, faster waves.
- Deep sleep is important for feeling refreshed in the morning; it's during this stage that the body repairs muscles and tissue, stimulates growth and development, boosts immune function, and builds energy for the following day.