The different types of sleep and the benefits of each
There are five sleep stages and they are all equally necessary. However, they are not all equally featured in pop music and, hence, are not all equally as well known. Sleep stages were first distinguished through the use of the electroencephalograph (EEG) – a series of electrodes that are stuck to a scalp and detect the brain’s electricity. They produce a graph showing various brain waves. These waves have been measured and named and we now have a fair idea of what “normal” brain activity looks like during sleep.
The first four stages fall into the category of ‘Quiet Sleep’ also known as non rapid eye movement sleep (NREM).
Stage 1 – THETA WAVES - The first 5-10 minutes of sleep are seen on an EEG as Theta waves. This period is characterized by light sleep and myoclonic jerks.
Stage 2 – SLEEP SPINDLES - The next 20 minutes of sleep is characterized on an EEG as ‘Sleep Spindles’. Sleep spindles are clusters of brain waves that are intense bursts of electricity. These bursts are thought to cause brain elasticity which is essential for laying down new muscle memory. This is the time when your muscles relax, your body temperature drops and your heart rate decreases.
Stage 3 – CHANGING OVER - This is a short, transitional stage between light sleep and deep sleep. It is slightly deeper than stage 2.
Stage 4 – DELTA WAVES - Also known as Delta sleep this is the deep sleep stage that should ideally last 30 minutes. Behaviour characteristic of this stage includes sleepwalking and bedwetting.
Stage 5 – REM Sleep - Also known as Paradoxical sleep as whilst the muscles appear completely relaxed, the brain is at the peak of its electrical activity – most notably in the prefrontal area of the brain.
This area is responsible for human behavior – patience, judgment, strategy and reasoning. Research has shown that REM sleep helps to consolidate emotional human memories and prevent chronic mood disorders characterized by anxiety and depression.