Light therapy during sleep helps increase resistance to Alzheimer’s disease (AD) progression, a study in Frontiers of Optoelectronics suggests. The researchers found that photobiomodulation (PBM) during deep sleep improved the ability of the lymphatic system to flush beta-amyloid from the brains of mice, demonstrating the importance of sleep in fending off the neurodegenerative disease and opening a possible new therapy for prevention and treatment of Alzheimer’s.