Stages of Sleep
Different Stages of Sleep:
Stages of sleep are divided into two categories. One is NREM-sleep and the other is REM-sleep. Typically an individual transita from NREM sleep to REM sleep. REM sleep usually lasts for a short time span. Vivid dreams and other such events usually occur during REM sleep.
Transition: Stage 1
Stage one falls in the Non-rapid eye movement category. This is the basic stage of sleep that we usually encounter while scrolling through our Instagram feed or listening to music. During this stage the brain activity gets low, and a light drowsy feeling takes over, making you feel asleep. One’s sleep can easily be disrupted by noise or movement. You must have experienced that falling sensation during sleep; well, that usually happens in the early stages of Non-rapid Eye Movement sleep.
Light Sleep Stage: Stage 2
Stage 2, among the four stages, is usually comprised of 40-60% of our sleep. During this stage, the brain produces “sleep spindles”. Sleep spindles are basically waving of specific frequency responsible to put the mind at ease, make us feel relaxed, and prepare our brain to absorb newer information. It’s a light sleep stage where the brain activity gets slow and our brain starts producing slow-wave patterns. We all take power naps to wake up all the more energetic and refreshed? Well, these power naps fall into the category of the second stage of sleep. To send us into the third stage of sleep, our body temperature and heart rate drop a little further.
Deep Sleep: Stage 3
It’s usually called a “deep sleep stage”. The deep sleep stage comprises about 5-15% of our total sleep every night. Sleep during this stage is most restorative with minimum or no eye and muscle movement. Due to the slow production of delta waves, the human body is highly unlikely to experience any external stimuli during the deep sleep stage. If one manages to wake up from deep sleep by some external disturbance, it usually takes about good 5-10 minutes to understand what has been happening around.
According to the experts an average individual experiences about 4 to 5 REM’s every night. REM is considered to be the most active sleeping stage. During this stage, our heart and brain start picking up its normal pace. REM sleeping stage can occur anytime during the three stages, but usually, happen after 90 minutes of sleep. REM periods usually vary from one stage to another. It is observed to last for about 10 minutes during the transition state. Each session of the REM sleep as we progress towards deep sleep.