The importance of REM-sleep

World Sleep Day 18 March 2022

The importance of REM-sleep
by Truls Hotvedt

During the night our brain takes us through several phases of sleep; light sleep, deep sleep and REM sleep. In this article we will take you through the most exciting sleep phase, REM.

REM stands for Rapid Eye Movement and is characterized by eye movements that can be observed through closed eyelids. This is the sleep phase where we have the weirdest and most lively dreams. Brain activity in REM sleep is almost the same as when awake, which is why images are created, but muscle activity is paralyzed to prevent us from acting our dreams.

7-8 hours of sleep is ideal

For grownups 20 to 25 % of a night´s sleep is spent in the REM phase, which occurs mainly in the last half of your sleep. That´s why the REM phase suffers the most when you get too little sleep. Experts agree on the fact that grownups need 7 to 8 hours sleep to get enough of the REM-sleep, to feel rested and be well functioning throughout the day.

During REM sleep changes occur in several of the body´s systems, among others blood pressure, breath frequency and pulse.

REM heals your wounds

REM sleep has unique advantages. The brain receives a bath of neuro chemicals that processes painful memories. In the REM phase memories are reactivated and placed in the right context, in addition to lowering your stress hormones.

All this enables us to better handle some of the worst feelings from a memory over time.

Curing depression with dreams

A study showed that newly separated women suffering from depression had more emotionally strong dreams about their ex-husbands, than the women who were not that depressed. The most interesting discovery was that the women who recovered the fastest from depression after a divorce, were those who had the most intense and emotional dreams.

This indicates that REM-sleep and dreams have an important role in processing trauma and recovering after an emotional roller coaster.

REM sleep heals your wounds.


Studies even show that you´re in a better mood when you have enough time in the REM phase. If you suffer from lack of sleep, the area of the brain managing emotions (Amygdala) is very active. At the same time activity in the neural pathways from the impulse control centre to Amydala in the brain is lower.

This results in less control of strong emotions like anger, which makes us grouchy in the morning. You need your REM sleep to wake up with a light mood.

«Sleep on it»!
Did you know that Beatles´ “Yesterday” came to Paul McCartney during a dream in 1964? He woke up, went to the piano, found the tunes from his dream and the world famous song was a fact.

The professional golfer, Jack Nicklaus, dreamt about a round of golf that was unusually successful. He discovered a different grip in his dream. When he tried it in real life, his golf skills were significantly improved.

REM and knowledge

The light and deep sleep play a role in processing, sorting and storing new information. In the REM phase the brain spends as much energy, sometimes even more, as when you are awake. REM could be compared to group therapy for memories, where your brain checks links and associations between new knowledge and old memories and experiences. In this way your brain creates new connections.

The light and deep sleep is about collecting and storing, while REM sleep is about wisdom, how we understand new knowledge and how we use it.


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