Gamma Frequency Stimulation in Individuals With Down Syndrome

Down Syndrome (DS) is characterized by an additional copy of chromosome 21, which also increases risk of Alzheimer's Disease (AD). The investigators' lab found a non-invasive way to remove toxic proteins from the brain in AD mouse models. Remarkably, treated mice also have improved memory on behavioral testing. The investigators then translated this non-invasive method, which uses light and sound to stimulate the brain, to be used in mild Alzheimer's patients and cognitively normal adults. The investigators have also translated this research into a vibrating speaker device to study tactile vibration to stimulate the brain as well. For the present study, 30 participants with Down Syndrome and 30 cognitively normal adult controls will be recruited, and the investigators will assess their brain waves with electroencephalogram (EEG) during light, sound, and tactile stimulation. The investigators will also test for safety, feasibility, and cognitive performance before and after a 30-60 minute session of light and sound stimulation to optimize the stimulation devices for use in the DS population.