The HeadSense (HS) HS-1000 device, a new non-invasive brain monitor is expected to safely and accurately monitor concussed patients with minimal discomfort, potentially providing a new modality for concussion measurement. The device is based on advanced signal analysis algorithms that analyze a very low frequency acoustic signal (within the audible range) generated by the device. The acoustic signal is transmitted using a small transmitter, placed in the participant's ear, and picked by an acoustic sensor placed in the other ear.