The brain is made up of approximately 20% neurons, which are involved in thinking and memory, and approximately 80% glial cells, which maintain and manage the brain. Glial cells are cells whose role has been elucidated and clarified since around 2010. It is generally known that a person’s sensibilities develop by the age of 2 or 3, and the basic neural circuits for thinking are formed by the age of 12. It is also known that new neural circuits are generated even after adulthood, although it takes time.
Glial cells are active during sleep and work to maintain and manage the brain on a daily basis. In order for glial cells to function properly, it is necessary to get enough sleep every day. The ideal amount of sleep is 7 hours.