(i) Impaired consciousness. Most apparent head trauma is a closed injury with a period of loss of consciousness that may range from a mild concussion to a prolonged coma. If the trauma is severe and the loss of consciousness lasts more than a few hours, the chances of full recovery may be reduced. (ii) Memory impairment: It can be divided into 1. Post-traumatic amnesia (PTA), also called paratraumatic amnesia, includes the trauma phase and the post-traumatic phase (until normal memory is restored), i.e., the patient forgets the experience of the traumatic brain injury at that time and for a period of time afterwards, usually ranging from several minutes to several weeks. Behavior during this phase is usually normal. Post-traumatic amnesia can end abruptly. 2. Retrograde amnesia (RA) is when the patient forgets the experiences of the period before the injury, including the period from the last clear session before the trauma to the trauma itself. It is usually a dense type of amnesia that is brief, lasts for a few seconds or minutes, and gradually fades. (iii) Acute post-traumatic delirium (PTD): A state that occurs after severe head trauma and occurs as the individual begins to recover. It is sometimes referred to as “post-traumatic psychosis” and is characterized by prolonged and variable confusion with or without behavioral symptoms, anxiety, emotional instability, paranoia, delusional misinterpretation, and hallucinations.