The Gamma Instrument is a small-format interactive device hovering between the realms of musical instrument and medical instrument. A capacitive hand-following interface allows one to create abstract gamma sounds while surrounded by an orbit of gamma-frequency lights. Creating musical tones on the device could heighten gamma entrainment as it mimics higher-level cognition and gamma-band processing noted in musicians. This device is part of a larger exploration of 40 Hz frequencies and Alzheimer’s prevention/reduction within the context of the Aging Brain Initiative at MIT. The tabletop multi-sensory experience brings aspects of the Cognitarium to an interactive and portable platform.