Longevity & AgingHow the Brain Cleans Itself During Sleep and Why It Matters for Aging
A major collaborative review in Neuron synthesizes a decade of research on the glymphatic system—the brain's waste-clearance network—and its deep links to immune surveillance. CSF flows along periarterial spaces into brain tissue, collects metabolic waste, and exits via perivenous routes and meningeal lymphatics toward cervical lymph nodes. This process is most active during sleep, driven by vasomotion, neural activity, and norepinephrine-mediated vascular oscillations. Immune cells stationed at brain borders monitor outgoing solutes and modulate fluid flow, connecting clearance to neuroimmune signaling. Disruption of these systems is implicated in Alzheimer's disease, neuroinflammation, and psychiatric disorders, making the glymphatic-lymphatic axis a high-priority therapeutic target.
