Interested volunteers will complete a brief initial in person or phone consultation with a member of the study team and those who meet eligibility criteria and wish to participate will be invited for a study visit in the testing facility. During this visit, a member of the study team will describe the study in greater detail, verify subject eligibility, obtain informed written consent/assent for study participation, and record relevant demographic, medical history information, concussion history and clinical assessment questioners as provided by the subject or as available from subject's medical records. The subject will then have the EEG electrode cap placed on their head and will undergo the BNA test after a brief training and instructional session.