Global brain activity seen on fMRI, and its connection with cerebrospinal fluid flow weaker in brains of individuals with Alzheimer’s disease risk or related toxin buildup.

Evidence of sleep-dependent low-frequency (0.1 Hz) global brain activity in the clearance of Alzheimer’s disease-related toxin buildup is presented in research published today (June 1, 2021) in the open access journal PLOS Biology by Xiao Liu and colleagues at The Pennsylvania State University. This neuronal activity was more strongly linked with cerebrospinal fluid flow in healthy controls than higher risk groups and patients, and the findings could serve as a potential imaging marker for clinicians in evaluating patients.

The development of Alzheimer’s disease is believed to be driven by the buildup of the toxic proteins amyloid-β and tau in the brain. The brain’s glymphatic system plays a crucial role in clearing these toxins and previous work has shown a possible relationship between sleep-dependent global brain activity and the glymphatic system by showing this activity is coupled by cerebrospinal fluid flow essential for the glymphatic system.