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How the Brain Dumps Its Trash [Video]

A recently discovered waste-removal system is a linchpin in preserving neural health

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The brain gets rid of some 1.5 kilograms of waste products a year, equivalent to its own weight. One puzzle: Where does its built-in garbage disposal reside? New findings that reveal detritus-carrying passages—what is called the glymphatic system—traffics the brain’s discarded leavings.

Much of this activity, moreover, occurs during sleep. Manipulating the glymphatic system may be a new way to treat Alzheimer’s and other neurodegenerative diseases by removing buildups of toxic proteins. Watch a talk on the glymphatic system by Maiken Nedergaard, author of “Brain Drain” in the March Scientific American.

Gary Stix is the former senior editor of mind and brain topics at Scientific American.

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Scientific American Magazine Vol 314 Issue 3This article was published with the title “How the Brain Dumps Its Trash [Video]” in Scientific American Magazine Vol. 314 No. 3 ()
doi:10.1038/scientificamerican032016-2HW6RLTYRQu9ssAreQ0PnV

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