Have you heard of a robbery in which someone entered the house and stole something while the owner was sleeping? And you wondered how the owner woke up to the sound of someone invading their home. The owner is almost certainly sleeping deep at the time. Sleep is a complex yet fascinating process, and is very important for our emotional and physical wellbeing.Sleep occurs in stages, and we spend different amounts of time in light and deep sleep. All stages are important, but they serve distinct functions. In this blog, we’ll learn about the different stages of sleep,the importance of each stage, and which stage is the most important. Stages of Sleep Before we can determine which sleep stage is most important, it's important to understand the journey our bodies undergo as we sleep. Sleep is divided into two main categories: non-REM (NREM) sleep and REM sleep. Each category comprises distinct stages characterized by different brain wave patterns and physiological activities. Non-REM sleep occurs first and has three stages. The final stage of non-REM sleep occurs when you sleep deeply. It's difficult to wake up from this stage of sleep. REM sleep occurs approximately an hour to an hour and a half after falling asleep. REM sleep is when you have vivid dreams. 1. Non-REM Sleep Stage 1: This stage of non-REM sleep is the typical transition from consciousness to sleep and usually lasts a few minutes. Stage N1 is the lightest stage of sleep; patients awakened from it typically have no idea that they were genuinely asleep. Stage 2: This following stage of non-REM sleep makes up almost all of total sleep time and is considered as a lighter period of sleep from which you can easily be awakened. This is the stage before you go deeply asleep. Stage 3 and 4 (Slow-Wave Sleep): The final stage of non-REM sleep is the deepest. Stage N3 sleep is sometimes known as slow-wave or delta sleep. During this final non-REM state, your body performs a number of vital health-promoting functions. 2. REM Sleep There are two phases of REM sleep: phasic and tonic. Phasic REM sleep includes bursts of fast eye movements, whereas tonic REM sleep does not.Stage R starts approximately 90 minutes after falling asleep and is the predominant