Neuroscientist Dr. Haru Cuts Through the Noise — Vol. 1: A Sleep-Deprived Brain Is a Waste Dump

Everyone has experienced feeling out of sorts the day after a poor night's sleep, feeling fuzzy-headed and unfocused. Why does this happen? We asked neuroscientist Dr. Haru to explain. Is your brain accumulating harmful substances?

Is it related to youth and hormones!? The dangers of neglecting a sleep-deprived brain

Surely everyone has experienced mornings that are tough, or minds that feel dull? This isn't just a matter of mood; in fact, a lack of sleep means our body tissues and brain haven't sufficiently recovered their energy.

When we are awake and active, waste products and reactive oxygen species generated by metabolic functions accumulate in our body tissues, and if left unchecked, these can cause significant stress to our cells. During sleep, body temperature, heart rate, and energy consumption in the brain decrease, and metabolic activity slows down. During this time, the body's repair mechanisms take over, and waste products are removed.

For example, it is known that the brain removes waste products more efficiently during sleep than when awake. Furthermore, glycogen, which the brain uses as energy, is depleted during waking hours like a rechargeable battery, and then replenished in the brain during sleep.

The brain also influences physical recovery. During sleep, the brain releases hormones that promote blood vessel regeneration and tissue growth. Physical recovery is important in daily life, and especially crucial when injured. It is known that sleep deprivation reduces the body's ability to recover from injuries. The brain's job during sleep is detoxification and energy charging. To start each day feeling refreshed both physically and mentally, be sure to get enough sleep!

Dr. Haru's Profile:
Haruhisa Okawa
Graduated from the University of Tokyo. Received a Ph.D. in Neuroscience from the University of Southern California.
Subsequently, spent approximately seven years conducting research as a neuroscientist at the University of Washington.
Later, served as a project manager for neurological projects at a foreign-affiliated pharmaceutical consulting firm.
Currently works at a foreign-affiliated pharmaceutical company in the central nervous system division. 

References:

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