Stages of sleep explained in clear terms, showing how sleep unfolds through the night and why order, timing, and consistency affect rest ...

The sleep cycle has three NREM stages and one REM stage. Deep sleep occurs in stage 3 and is crucial for feeling refreshed. REM sleep helps in processing and storing memories. As we sleep, our brain ...

The locus coeruleus is a region of the brain that is instrumental in coordinating our mental processing and is the primary source of noradrenaline in the brain, which acts to regulate arousal states ...

Learn facts about sleep, during which the body rests, recuperates and performs essential repairs. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.