Sleep Stages
As you are falling asleep, the activity in your body slows down.
Stage 1
Also known as NREM, N1, or simply “dozing off stages” is where you experience somnolence, or drowsy sleep. This is the transitional phase. Your brain’s alpha waves turn to theta waves, eyes roll slowly, and muscle tone starts to decrease. Although your body has started to relax, it is unlikely that your facial and throat muscles have relaxed to the point where you are snoring yet.
NREM2 stage
In this stage all the muscles in your body fully relax. This is where your tongue collapses into your throat and causes the obstruction that result in your snoring. The average non-snoring adult spends about half their sleeping time in this second stage. Unfortunately, snorers spend a lot more time here.
Stage 3
During NREM3, delta waves emerge, which are very slow brain waves. This is is the transitional period into the deepest sleep stage. Slow wave sleep is suggested to be the most restful stage. This is a restorative period.
This is also the stage where parasomnias occur, such as night terrors, Somniloquy, etc.