Diagnosis of transient global amnesia rests on excluding more-serious conditions — stroke, seizure or head injury, for example — that can cause the same type of memory loss.
The process begins with a neurological exam, checking reflexes, muscle tone, muscle strength, sensory function, gait, posture, coordination and balance. The doctor may also ask questions to test thinking, judgment and memory.
Brain and imaging tests
The next step is to conduct tests that detect abnormalities in the brain's electrical activity and circulation. The most common of these tests are painless and take less than two hours each:
- Magnetic resonance imaging (MRI). This technique uses a magnetic field and radio waves to create detailed, cross-sectional images of the brain. The MRI machine can combine these slices to produce 3-D images that may be viewed from many different angles.
- Electroencephalogram (EEG). An EEG records the brain's electrical activity via electrodes attached to the scalp. People with epilepsy often have changes in their brain waves, even when they're not having a seizure.
- Computerized tomography (CT). Using special X-ray equipment, your doctor obtains images from many different angles and joins them together to show cross-sectional images of the brain and skull. CT scans can reveal abnormalities in brain structure, including narrowed, overstretched or broken blood vessels and past strokes.
No treatment is needed for transient global amnesia. It resolves on its own and has no confirmed aftereffects.
Preparing for your appointment
Anyone who experiences sudden loss of memory for all events leading up to the present needs emergency medical care. Call 911 or your local emergency number immediately.
If a friend or family member develops these symptoms in your presence, go with him or her to the hospital. Because he or she doesn't remember recent events, you'll need to provide important information to the doctor.
What you can do
- Stay with the person through the full medical evaluation. Sudden memory loss may indicate a serious health problem. Take an active role in noting all the information the doctor provides and in helping to make decisions about next steps.
- Share with medical staff physically or emotionally stressful events that preceded the memory loss. Important details include conflict or anxiety at work or at home, strenuous physical activity, sudden immersion in hot or cold water — anything that may have caused the person alarm or strain.
- Note any accompanying signs or symptoms, such as numbness, weakness or trembling.
- Relay key medical information, including any other conditions with which the person has been diagnosed. Also include all medications he or she is taking.
- Write down questions to ask the doctor.
Prepare a list of questions to ask the doctor on the person's behalf. Although people experiencing transient global amnesia can think and speak, it's likely that they will be feeling severe distress. For transient global amnesia, some basic questions include:
- What is most likely causing the symptoms?
- What are the other possible causes for these symptoms?
- What kinds of tests do you recommend?
- Is any treatment needed now?
- What signs or symptoms should I be watching for at home?
- What signs or symptoms should prompt calling 911 or emergency medical help?
- How soon do you expect the symptoms to improve?
- Do you expect a full recovery?
- Are there any steps to take to prevent a recurrence of this problem?
- What is the risk of long-term complications from this condition?
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions as they occur to you during the appointment.
What to expect from your doctor
The doctor is likely to ask both you and the person experiencing amnesia a number of questions about symptoms and about the period leading up to the memory loss.
The doctor may ask your loved one:
- What is the last thing you remember?
- Do you know who you are?
- Do you know the person who came with you?
- Do you have any symptoms other than memory loss?
- Are you dizzy?
- Are you having problems with balance or coordination?
- Do you feel weakness or numbness on either side of your body?
- Are you having any vision problems?
- Do your symptoms include headache?
To determine the extent of memory loss, the doctor may check your loved one's knowledge of general information — such as the name of the current president — and assess his or her ability to recall a random list of words.
The doctor may ask you:
- When did the person's memory loss begin?
- Did the memory loss come on gradually or suddenly?
- Has anything like this ever happened before?
- What happened just before the memory loss?
- Did the person experience an accident that may have injured his or her head?
- Has the person recently experienced significant stress, conflict or loss?
- Has he or she had a seizure since symptoms began?
- Has the person been diagnosed with any other medical conditions?
- Does he or she have a history of migraines?
- Has the person recently undergone any medical procedures or surgery?
- What medications is he or she taking, including prescription drugs, over-the-counter medications, herbs and supplements?