Researchers in South Korea say they have finally worked out how the brain flushes away waste – offering a clearer picture of the processes involved in dementia and other brain disorders that could one day be harnessed to treat them. The breakthrough, published this month in journal Cell, solved a puzzle that has stumped scientists since lymphatic vessels around the brain were first discovered roughly 250 years ago: how does our body clear away the waste? A doctor inspects a brain scan for signs of possible disease. Dementia is characterised by a build-up of toxic brain waste. Photo: Handout“We have finally clarified the long-standing mystery of how cerebrospinal fluid crosses the arachnoid membrane,” Koh said, referring to the delicate, weblike middle layer of tissue that acts as a protective wrapper for the brain and spinal cord.