Here's a wonderful article on an exciting development in the role of glial cells and CSF in the brain.Previously Unknown Cleaning System in Brain: Newer Imaging Technique Brings 'Glymphatic System' to LightThe highly organized system acts like a series of pipes that piggyback on the brain's blood vessels, sort of a shadow plumbing system that seems to serve much the same function in the brain as the lymph system does in the rest of the body -- to drain away waste products."ScienceDaily (Aug. 15, 2012) — A previously unrecognized system that drains waste from the brain at a rapid clip has been discovered by neuroscientists at the University of Rochester Medical Center. The findings were published online August 15 in Science Translational Medicine. Waste clearance is of central importance to every organ, and there have been long-standing questions about how the brain gets rid of its waste," said Maiken Nedergaard, M.D., D.M.Sc., senior author of the paper and co-director of the University's Center for Translational Neuromedicine. "This work shows that the brain is cleansing itself in a more organized way and on a much larger scale than has been realized previously."We're hopeful that these findings have implications for many conditions that involve the brain, such as traumatic brain injury, Alzheimer's disease, stroke, and Parkinson's disease," she added.Nedergaard's team has dubbed the new system "the glymphatic system," since it acts much like the lymphatic system but is managed by brain cells known as glial cells. The team made the findings in mice, whose brains are remarkably similar to the human brain.