Information processing in the brain is thought to occur through synchronized neuronal activity in the form of network oscillations. Activity in the 30-100 Hz range is considered gamma-band oscillation and has been reported to be critical for attention, memory formation, and recall. Disruptions of gamma oscillations, particularly in the 30 - 50 Hz range, are reported as a potential early hallmark of Alzheimer's disease.
40Hz gamma frequency stimulation was previously shown to reduce Alzheimer's disease pathology and improve cognitive outcomes. This study aims to:
1. Determine whether non-invasive 40Hz sensory stimulation (ie, light, sound, tactile) can change brain activity.
2. Evaluate whether devices delivering non-invasive 40Hz sensory stimulation are safe in cognitively normal adults.
3. Determine whether non-invasive 40Hz sensory stimulation can change brain connectivity, neuropsychological measures, blood biomarkers, and the microbiome.