The Journal Club returns to the Lifespan.io Facebook page with Dr. Oliver Medvedik as your host on Friday, March 22nd at 12:00 Eastern time. This new paper further explores the approach of using light and sound stimulation to help combat Alzheimer’s disease.
The Mindset project
This is a subject close to our heart, as Dr. Medvedik and Lifespan.io are working on developing the Mindset project. The project aims to target Alzheimer’s disease using a headset that stimulates the brain with light and sound in order to trigger neural entrainment. Neural entrainment refers to the observation that brainwaves will naturally synchronize to the rhythm of periodic external stimuli, including flickering lights and sounds. Evidence suggests that triggering neural entrainment may reduce the loss of functional connectivity, combat brain atrophy, and improve cognitive function.
Abstract
The glymphatic movement of fluid through the brain removes metabolic waste. Noninvasive 40 Hz stimulation promotes 40 Hz neural activity in multiple brain regions and attenuates pathology in mouse models of Alzheimer’s disease. Here we show that multisensory gamma stimulation promotes the influx of cerebrospinal fluid and the efflux of interstitial fluid in the cortex of the 5XFAD mouse model of Alzheimer’s disease. Influx of cerebrospinal fluid was associated with increased aquaporin-4 polarization along astrocytic endfeet and dilated meningeal lymphatic vessels. Inhibiting glymphatic clearance abolished the removal of amyloid by multisensory 40 Hz stimulation. Using chemogenetic manipulation and a genetically encoded sensor for neuropeptide signalling, we found that vasoactive intestinal peptide interneurons facilitate glymphatic clearance by regulating arterial pulsatility. Our findings establish novel mechanisms that recruit the glymphatic system to remove brain amyloid.
