Disrupted Sleep Rhythms May Impair Brain Cleaning, Raising Dementia Risk

A University of Rochester review argues that chronic stress, depression, aging, and cardiovascular disease may converge on disrupting sleep-dependent brain rhythms that drive the glymphatic system, which clears toxic proteins like amyloid-β and tau. When these synchronized neuromodulator cycles and vasomotion fail to function during non-REM sleep, waste clearance falters, potentially elevating dementia risk. The piece also suggests heart rate variability during sleep as a noninvasive biomarker, trackable by wearables, to gauge brain-cleaning efficiency before symptoms appear.