### Architecture of Sleep We drift through 6 stages of sleep : 4 Non-REM and 2 REM stages. All six serve different purposes, and a balanced rest allows us to recover on almost every level. REM (Rapid Eye Movement) sleep is the wildest phenomenon. Brain activity and sympathetic nerve activity levels increase up to 30% higher than wakefulness. Here, tagged neurons re-fire at half the usual rate, and memory consolidation occurs. Non-REM (NREM) sleep has varying depths and purposes. The deeper you go, the slower the brainwaves and deeper the recovery. Tagged neurons can re-fire up to 15 times faster in spindles upon slower wavelengths, which leaves you both adequately recovered and smarter. ### Resources for Sleep Science 1. [Huberman Lab](https://www.hubermanlab.com/topics/sleep-hygiene) 2.