The glymphatic system uses cerebrospinal fluid to wash out toxic substances like amyloid-beta from the brain.

“your brain we now know is cleaning itself you know during the time in which we're sleeping thanks to the newly discovered glymphatic system you know proteins like amyloid and tau these proteins are flushed out when we go to sleep”

“if your blood-brain barrier can't hold the back pressure which is what would be the case if it were permeable you would not have the back pressure to maintain glymphatic flow”

“the blood-brain barrier is essential for removing toxic compounds from the brain and a variety of different processes you know happen to allow this to occur so for example you you activate the lymphatic system during sleep right and a lot of people are aware of this your brain sort of swells during sleep and the lymphatic system is pushing the cerebral spinal fluid through the brain clearing out debris amyloid plaques you know things like that”

“The glymphatic system, which is what Dan was referring to when he was talking about how cerebral spinal fluid squirts up through the brain, washes out all the toxic substances, including amyloid-beta, which aggregates outside of neurons and is thought to play a role in disrupting synapses, the connection between neurons and things like that, is really important.”