The term Post Traumatic Amnesia (PTA) refers to that period of time and the mental state that occurs right after a traumatic brain injury. It’s a difficult period of time when the injured person is confused, disoriented and can’t remember important things like where is he, what is his name or what time it is. Also he might be unable to remember what happened after the injury.
Both retrograde and anterograde amnesia occurs during the PTA (Post Traumatic Amnesia). Retrograde Amnesia refers to the memories formed (shortly) before the injury. And the anterograde amnesia refers to the lack of ability to form new memories after the injury.
The most popular case is that of the quarterback who lead a football team after a concussion but the next day he couldn’t remember a thing about the game or anything that happened after the injury took place.
Considered a hallmark of a concussion, PTA is used to predict the severity of a concussion. When people experience loss of consciousness or longer periods of amnesia right after an injury, it means the person might need longer time for recovery.
The duration of the PTA is hard to measure as there are many factors to consider. For example a patient might be under the influence of alcohol or drugs or maybe asleep. In this case the duration will be overestimated. But it could also be underestimated if parts of the memories are back before the recovery of the continuous memory.
Right after the concussion people might react in different ways. Many times they are unable to recognize familiar people or are confused agitated, anxious and distressed. Sometimes they might display an uncharacteristic behavior such as shouting, swearing, violence, disinhibition, aggression. In other cases people are friendly, silent, loving and docile. Also they might have a tendency to wander.
PTA might last from a few minutes to weeks and sometimes, in rare cases, even months. Depending on the duration of the PTA the severity and recovery is can be estimated.
If it lasted up to one hour full recovery is expected because this is a very mild PTA. When it lasts from 1 to 24 hours full recovery is expected as well as the injury is just moderate. If it lasts more than one day and up to 7 days we enter the territory of severe injury and it means recovery might take weeks or even months.
In case it lasts between 1 and 2 weeks the recovery might take months and the patient might experience long-term symptoms such as decreased performance on virtual tests and decreased verbal and non-verbal intelligence.
If it lasts more than 2 weeks it is very likely for the affected person to display permanent disabilities affecting memory and cognitive functions. It’s very likely that the patient won’t be able to return to work.
Many times the memories before the trauma are also lost because the memories might not be transferred already from the short-term to long-term memory as the event might interrupt the process.
In case of PTA immediate assistance of a doctor is necessary. The PTA is also a stage that follows a coma.