NeuroNation \ Healthy Living, Mind and Brain

Why Dreams Are Important for Health

For years, scientists have wondered why almost all animals – including humans – sleep for quite a long time every day, even though being unconscious is a great disadvantage for survival. Shouldn’t this need have been displaced or at least re-placed by evolution long ago? A team of researchers at the University of Tsukuba (Japan) has been studying this question and, it seems, has found an answer.

Promising discovery

While we sleep, in addition to the processes of “synaptic cleansing”, which is the reduction of unimportant connections (synapses) between brain cells and regeneration, another process takes place in our heads: an intensive flow of red blood cells.

This process takes place exclusively during the so-called Rapid-Eye-Movement (REM) phase. Usually, the process of dreaming also takes place during this phase. In adults, the REM phase accounts for about 20 to 25% of the total sleep time. 

“We were surprised by the results,” explains Professor Hayashi. “There was a massive flow of red blood cells through the brain capillaries during REM sleep, but no difference between non-REM sleep and the awake state, showing that REM sleep is a unique state”.

Considering that a decreased blood flow in the brain and shorter periods of REM sleep are correlated with the development of Alzheimer’s dementia disease, in which plaques are decreasing the ability of the brain cells to forward information, it may be interesting to investigate whether increased blood flow in brain capillaries during REM sleep is responsible for the process of cleaning the brain from such plaques and other waste products.

This study lays the groundwork for future investigations, which could ultimately lead to the development of new treatments for neurodegenerative diseases, such as Alzheimer’s.

Prevention instead of treatment – with NeuroNation

If you don’t want to wait for future discoveries, but want to actively do something against neurodegeneration now, we recommend reaching for your brain training regularly. Studies show that cognitive training can reduce the likelihood of developing dementia by up to 30%.

Over 20 million people around the world have already discovered NeuroNation brain training and put their trust in us. NeuroNation’s personalized and scientifically proven exercises, together with proper lifestyle, form a reliable foundation for a long and fulfilling life.

At NeuroNation you are in good company: Researchers from Australia to Canada use NeuroNation in innovative studies to improve mental and cognitive health.



Chia-Jung Tsai, Takeshi Nagata, Chih-Yao Liu, Takaya Suganuma, Takeshi Kanda, Takehiro Miyazaki, Kai Liu, Tsuyoshi Saitoh, Hiroshi Nagase, Michael Lazarus, Kaspar E. Vogt, Masashi Yanagisawa, Yu Hayashi. Cerebral capillary blood flow upsurge during REM sleep is mediated by A2a receptors. Cell Reports, 2021; 36 (7): 109558.

Edwards, Jerri & Xu, Huiping & Clark, Daniel & Ross, Lesley & Unverzagt, Frederick. (2016). THE ACTIVE STUDY: WHAT WE HAVE LEARNED AND WHAT IS NEXT? COGNITIVE TRAINING REDUCES INCIDENT DEMENTIA ACROSS TEN YEARS. Alzheimer’s & Dementia. 12. P212. 10.1016/j.jalz.2016.06.373.

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