Posttraumatic amnesia

Posttraumatic amnesia (PTA) is a state of confusion that occurs immediately following a traumatic brain injury (TBI) in which the injured person is disoriented and unable to remember events that occur after the injury. The person may be unable to state their name, where they are, and what time it is. When continuous memory returns, PTA is considered to have resolved. While PTA lasts, new events cannot be stored in the memory.

There are two types of posttraumatic amnesia: anterograde and retrograde. Anterograde amnesia is the inability to create new memories after the event that caused the amnesia, leading to a blank space in the timeline. Retrograde amnesia is the inability to recall events that occurred before the incidence of amnesia, the loss of pre-existing memories.

Causes

Posttraumatic amnesia is caused by damage to the brain cells that form the hippocampus, which is involved in memory formation. The damage can be caused by a traumatic brain injury, such as a blow to the head, a brain infection, or a condition that deprives the brain of oxygen.

Diagnosis

Diagnosis of posttraumatic amnesia is based on symptoms and the absence of memory for events. The Glasgow Coma Scale (GCS) is often used to assess the severity of brain injury and the likelihood of posttraumatic amnesia. The duration of PTA can also be a useful predictor of the severity of the brain injury and the likely outcome.

Treatment

Treatment for posttraumatic amnesia focuses on rest and rehabilitation. Cognitive therapy may be used to improve memory and problem-solving skills. Medications may be used to manage symptoms.

Prognosis

The length of posttraumatic amnesia is a good indicator of the severity of the brain injury. The longer the period of amnesia, the more severe the injury is likely to be. Recovery can be complete or partial, depending on the severity of the injury.

See also

• Traumatic brain injury
• Amnesia
• Memory