Concussion and Post Traumatic Stress in Traumatic Brain Injury

Inclusion Criteria: * All patients will be recruited from the Bellevue Hospital Emergency Services (Emergency Department and Trauma Bay) or from among inpatient populations at Bellevue Hospital. They will need to be consentable and able/willing to participate and meet criteria for distribution into one of the three subject populations (structural TBI, non-structural TBI, injured/non-TBI) described here: * mild to moderate structural traumatic brain injury (TBI) as evidenced by CT scan demonstrating the presence of hemorrhage (subdural, epidural, subarachnoid or intraparenchymal), brain contusion, or skull fracture. * non-structural TBI(concussion), meaning no signs of structural injury on imaging; however, they complain of usual brain injury symptoms such as headache, dizziness, cognitive impairments, etc., A subject with a traumatically induced physiological disruption of brain function, manifested by \>1 of the following: * Any period of loss of consciousness (LOC). * Any loss of memory for events immediately before or after the accident. * Any alteration in mental state at the time of accident (i.e. feeling dazed, disoriented, or confused). * Focal neurological deficit(s) that may or may not be transient, but where the severity of the injury does not exceed the following: 1. Loss of consciousness of approximately 30 minutes or less 2. After 30 minutes, an initial Glasgow Coma Scale (GCS) of 13-15 3. Posttraumatic amnesia (PTA) not greater than 24 hours. * Non-brain injured subjects that have suffered some type of injury such as to the extremities or other parts of the body. The subjects will have sustained a blunt or penetrating trauma such as, to the corpus or extremities (i.e. car accident, falling). Exclusion Criteria: * Subjects that receive minor penetrating trauma insufficiently traumatizing to result in sufficient sequelae will be excluded. * Subjects suffering burns, anoxic injury or multiple/extensive injuries resulting in any medical, surgical or hemodynamic instability will also be excluded. * Particularly for the purposes of eye tracking all subjects that are blind (no light perception), are missing eyes, do not open eyes will be excluded from the research. * It is pertinent that subjects be able to detect light and have both eyes in order for the eye tracking data to be effective and significant. * Any physical or mental injury or baseline disability rendering task completion difficult will be excluded, also inability to participate in longtitudinal care, or obvious intoxication or blood alcohol level greater than 0.2. * Pregnant individuals and prisoners will also be excluded from the study.