The sleep cycle refers to the pattern of brain activity that occurs during a typical night's sleep. It consists of several stages of sleep, each with its own unique characteristics and functions.
There are two main types of sleep: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. During a typical night's sleep, a person will go through several cycles of NREM and REM sleep, with each cycle lasting around 90–120 minutes.
NREM sleep is divided into three stages, each with its own distinct characteristics:
* Stage 1: This is the lightest stage of sleep, and people can be easily woken up during this stage.
* Stage 2: This is a slightly deeper stage of sleep, and the brain waves become slower and more regular.
* Stage 3: This is the deepest stage of sleep, and it is difficult to wake up during this stage. This is also the stage where the body repairs and regenerates tissues and cells.
REM sleep, on the other hand, is characterised by rapid eye movements, increased brain activity, and vivid dreams. It is believed to be important for memory consolidation and emotional regulation.
The length and order of the sleep stages can vary from person to person and can be affected by a variety of factors, such as age, sleep disorders, and medication use.
Sleep cycle
Related Semantic Entities for Sleep cycle