We knew that sleep relates to plasticity. Now evidence emerge pointing to another vital role of sleep.
"Humans spend on average one-third of their lives sleeping. If we don’t, a slew of symptoms ensue including mental fatigue, poor decision-making, impaired learning, and heightened risk for migraines. Yet, we still don’t know why we need sleep. Now Lilu Xie and colleagues have found new evidence for why getting our nightly shuteye is vital. During sleep, mice have a greater flow of fluid moving in the areas between brain cells. Much like an aquatic garbage truck, this fluid cleans the brain of toxic metabolites—waste that brain cells secrete during waking hours. One such waste product is β-amyloid, a protein implicated in Alzheimer’s disease. When the researchers marked the β-amyloid with fluorescent tags, they observed the protein moving out of the brain two times faster in sleeping mice than in those that are awake. In fact, the total flow of fluid when awake is only 5 percent of what it is when asleep. As it turns out, sleep literally clears the mind. To learn more, read the Report: http://scim.ag/19Mjf3j, the News story:http://scim.ag/19Mj3RC, and the Perspective:http://scim.ag/19Mj7Rn"
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