[sci/bio/med] Sleep Washes the Soiled Synapses of Care
One of my favorite hypotheses as to Why Do We Need To Sleep -- which, let us be clear, is one of the greatest mysteries of biological sciences -- is that it's some form of what computer scientists call "garbage collection".
Recent evidence suggests that sleep is for what urban planners call "garbage collection": Scientists have just reported the first major mechanical reason our brains need to sleep - certain cleaning mechanisms in the brain work better when we shut the brain down. Just like how dump trucks take to the city streets during the pre-dawn hours because there's less traffic, our brain's cleaners also work best when there's less going on.
"This study shows that the brain has different functional states when asleep and when awake," study researcher Maiken Nedergaard, of the University of Rochester said in a statement. "In fact, the restorative nature of sleep appears to be the result of the active clearance of the by-products of neural activity that accumulate during wakefulness."
[...]
The paper was published in the journal Science on Oct. 17.
Toxic cells
All of our cells accumulate waste while they are working, and these waste products can be toxic. If they aren't removed they can build up and kill our cells. Throughout the rest of the body the lymphatic system washes these waste products away, but the brain is cut off from these actions because of the blood-brain barrier.
The team just discovered the brain's unique trash disposal system last year - the find was published in the journal Science Translational Medicine on Aug. 15, 2012. It works like a plumbing system.
The brain itself is bathed in a special clear liquid called cerebrospinal fluid, which doesn't mix with the blood and lymph system of the rest of the body. In the study from last year, they found that this fluid travels through special channels and washes the brain out.
There are two types of cells in the brain - the neurons that send signals and the glial that keep them healthy. They found that these glial cells seem to create these cleaning channels around the neurons.
It washes away toxic proteins and removes them from the brain's circulatory system. They are transferred to the general circulatory system, where the liver can remove them.
[...]
Lots more at this article.
tl;dr: When you sleep, your brain washes itself by throwing open its taps and flushing out the tubes.
Recent evidence suggests that sleep is for what urban planners call "garbage collection": Scientists have just reported the first major mechanical reason our brains need to sleep - certain cleaning mechanisms in the brain work better when we shut the brain down. Just like how dump trucks take to the city streets during the pre-dawn hours because there's less traffic, our brain's cleaners also work best when there's less going on.
"This study shows that the brain has different functional states when asleep and when awake," study researcher Maiken Nedergaard, of the University of Rochester said in a statement. "In fact, the restorative nature of sleep appears to be the result of the active clearance of the by-products of neural activity that accumulate during wakefulness."
[...]
The paper was published in the journal Science on Oct. 17.
Toxic cells
All of our cells accumulate waste while they are working, and these waste products can be toxic. If they aren't removed they can build up and kill our cells. Throughout the rest of the body the lymphatic system washes these waste products away, but the brain is cut off from these actions because of the blood-brain barrier.
The team just discovered the brain's unique trash disposal system last year - the find was published in the journal Science Translational Medicine on Aug. 15, 2012. It works like a plumbing system.
The brain itself is bathed in a special clear liquid called cerebrospinal fluid, which doesn't mix with the blood and lymph system of the rest of the body. In the study from last year, they found that this fluid travels through special channels and washes the brain out.
There are two types of cells in the brain - the neurons that send signals and the glial that keep them healthy. They found that these glial cells seem to create these cleaning channels around the neurons.
It washes away toxic proteins and removes them from the brain's circulatory system. They are transferred to the general circulatory system, where the liver can remove them.
[...]
Lots more at this article.
tl;dr: When you sleep, your brain washes itself by throwing open its taps and flushing out the tubes.