Post-Traumatic Amnesia - Fact Sheet

During consciousness the normal brain is constantly active - perceiving, processing and remembering information. A mild Concussion can cause a brief bout of PTA. A serious traumatic injury can lead to coma, with PTA following their reawakening.

When a patient responds with intentional movement or attempts to communicate, they are generally considered to have emerged from coma and progress to the PTA stage. These intentional movements include obeying an instruction to close the eyes or lift a limb and attempts to communicate by speaking, mouthing words or a gesture.

In PTA, the patient is confused and will have trouble with perception, thinking, memory and concentration. They will not be able to store continuous or recent memory, such as what happened just a few hours or even minutes ago. Individuals in PTA are partially or fully awake, but are confused about the day and time, where they are, what is happening and sometimes who they are. They may be afraid, disinhibited, agitated and restless. If physically able, they may wander. They may have hallucinations and delusional beliefs such as an adult believing he or she is a child. Behavioural changes can occur and the patient may be quiet and passive, or aggressive, abusive and agitated. Inappropriate comments and actions can occur due to Impulsivity.

Patients usually have little or no awareness of these Cognitive and behavioural impairments and usually will remember nothing of what happened during PTA, even though they were fully awake.

The rehabilitation process usually does not commence until PTA is finished. The patient’s memory is unable to retain information making most rehabilitation techniques ineffective.

There are usually two aspects to the amnesia associated with PTA. Retrograde amnesia is the partial or total loss of the ability to recall things that have occurred during the period immediately before brain injury. This improves with time, and the person may eventually be able to remember things up to 30 minutes before the injury.

The second aspect is anterograde amnesia, which is the reduced ability to form new memory after a brain injury, which may lead to decreased attention and inaccurate perception. This can go on to be a life-long issue even after PTA is finished, although gradual improvement should be noted particularly in the first year following the injury.

It is important to remember that this behaviour is due to the brain injury and that too much stimulation during this time can compound the person’s confusion and distress. They may not be able to cope with too much noise or activity. In some cases, even physical touch can be a sensory overload so watch carefully for cues that they may be upset by touch, noise, or even your presence. It may be necessary to limit the number of visitors to one or two at a time.

The positive aspect of PTA is that the person will usually not remember most, if any, of what has happened to them during this time. Families should be encouraged to get enough sleep and ‘time-out’ from the hospital to look after themselves. You may feel that you should be by your loved one’s side 24 hours a day, but you need to look after yourself, they need quiet times as well, and in any case, they may remember none of your support during this time.
Upon discharge, it is important to gauge how the person’s safety could be compromised as a result of their amnesia. Special precautions such as preventing the person from driving and not leaving them alone in the house may need to be taken.

PTA is usually seen as ending when the patient begin to retain information—such as where they are, why they are in hospital, and the month and year. These periods of clear thinking may alternate with confusion at first, so ideally assessment should take place at regular intervals to get a clearer picture of the degree of PTA.

The recovery period then commences, as should rehabilitation. Behavioural issues sometimes worsen at this point as they patient becomes aware of what has happened to them, and may have difficulty coping with the various emotions that arise.

Many consider the duration of PTA to be the best indicator of the severity of a brain injury. This also means it can give a rough indication as to the degree of recovery that can be expected.

In conjunction with the Glasgow Coma Scale, length of PTA is frequently used as a guide to the severity of brain injury. A commonly used interpretation of the scale involves the following:

A general finding is that if the PTA stage lasts for more than one week, ongoing cognitive problems can be expected.


Copyright Brain Injury Association of Queensland, Inc, Australia, 2007. This is one of a range of fact sheets made available by the Brain Injury Association of Queensland. While all care has been taken to ensure information is accurate, these fact sheets are only intended as a guide and proper medical or professional advice and information should be sought. The Association will not be held responsible for any injuries or damages that arise from following the information provided in these fact sheets. You can visit the Association’s website at www.braininjury.org.au or send emails to This email address is being protected from spam bots, you need Javascript enabled to view it