Inclusion Criteria:  Patients who meet all of the following inclusion criteria will be considered candidates for study enrollment:  Male or female subjects age 22 to 50 Patients with TBI who have a diagnostic head CT scan within 24 hours of the injury. For patients with TBI without intracranial hemorrhage, Glasgow Coma Scale score at enrollment of ≤ 14. For patients with TBI, intended clinical monitoring in the hospital setting for at least 6 hours from study enrollment. Signed written informed consent by study subject or, if subject is unable, by subject's next of kin or legal guardian. Willingness and ability to comply with schedule for study procedures. Control subjects with normal brain health.  Exclusion Criteria:  All subjects meeting any of the following criteria will be excluded from this study:  Female patients who are pregnant or lactating. Known history of seizure or clinical seizure prior to initiating SENSE monitoring. Open skull fracture. Metallic intracranial clip, coil, or device (such as metallic ICP monitor). Presence or history of any other condition or finding that, in the investigator's opinion, makes the patient unsuitable as a candidate for the SENSE device monitoring or study participation or may confound the outcome of the study. Planned placement of an intraventricular catheter after the diagnostic (pre-enrollment) CT. Planned withdrawal of care within 24 hours of enrollment. Planned intracranial surgery within 24 hours of enrollment. Current participation in a medical or surgical interventional clinical trial. Planned or current use of continuous EEG monitoring. Control subjects with normal brain health will have no known history of seizure, stroke, brain tumor, TBI