Larry A. Law
The recycle rate (the time needed for the brain to fully recharge) is 16 hours. The human brain begins to fail if it's awake too long. After 10 days with just 7 hours of sleep per night, the brain is as dysfunctional as it would be after staying up for 24 hours straight. And that may seem unbelievable given that so many people do not get 10 days of 7 full hours of sleep every night! It's typical to think, "I'll catch up on sleeping over the weekend" but the brain cannot catch up that way. An example of this inability to catch up is in the loss of memory mapping. Memories made each day are meant to be stored into long term storage every night. But if you don't get enough sleep, they don't make it in long term storage. In this way, the brain is damaged in ways that cannot be undone. Even though 6 or 7 hours of sleep per night may seem like a lot of sleep, the fact remains that it's not enough over the long term. The human brain needs 8-9 hours of consistent sleep for optimal health.
Another aspect of sleep deprivation is that it brings out the worst in us humans. Insufficient sleep results in mood swings. Deep emotional centers of the brain (located in striatum above and behind the amygdala) are bathed by the chemical dopamine. Lack of sleep can cause emotions to easily swing from one extreme (depression and worthlessness) to the other (aggression and violence). For these and other reasons, sleep should become a priority for all of us. Along with good nutrition, clean air and water, sleep is a necessary component of wellness!