Transient global amnesia

Transient global amnesia is a condition characterized by sudden, temporary memory loss that usually lasts for 2-10 hours. TGA is not due to the common neurological conditions such as stroke or epilepsy. If you have TGA, the recent memory will be lost, for example, you may not be able to recall where you are and how you got there. Fortunately, the condition is reversible and rare.

Symptoms

The most significant symptom of TGA is the inability of the patient to recall the recent past or to add new memories. Symptoms do not persist for more than 24 hours, and the memory returns gradually.

Repetitive questioning – Individuals with TGA are disoriented and keep questioning repeatedly about the time, place, and their present situation.

Unaffected cognition – The person can recognize people, name familiar objects and understand simple instructions.

The other associated symptoms include headache, dizziness, and nausea.

It does not involve loss of self-identity, clouding of consciousness or behavioral changes. Signs indicating damage to a part of the brain, such as involuntary movements, limb paralysis, or impaired word recognition are not produced. During the period of amnesia, the person does not experience seizures.

Causes

Although the exact cause of TGA is not known, the possible cause is a history of migraines. The below events can trigger TGA:

  • Mild head trauma

  • Acute emotional distress

  • Strenuous physical activity

  • Sexual intercourse

  • Sudden exposure to hot or cold water

  • Angiography or endoscopy

  • Risk factors

    It is usually more common among elderly people aged 50 and above. A high blood pressure or cholesterol, the conditions usually associated with an increased risk of stroke does not increase the risk of TGA.

    If you have migraine, then you are at higher risk of developing TGA compared to people without migraine.

    Complications

    TGA does not cause any direct complications but can affect the emotions of the affected person. It increases anxiety, and the patient has a fear of recurrence. TGA does not increase the risk for stroke.

    Treatment

    TGA treatment is not required because the condition resolves on its own without producing any other effects. If the cause is known, your doctor may provide the treatment for the condition triggering TGA.

    A physical examination is performed to check for sensory function, reflexes, muscle strength, muscle tone, posture, gait, coordination, and balance. The doctor may ask you certain questions to check your memory, thinking, and judgment.

    To detect any deviations in the brain’s activity and circulation, the below tests are conducted:

    Test type Purpose of the test

    Magnetic resonance imaging (MRI)

    Produces detailed, cross-sectional images of the brain which can be viewed for the presence of abnormalities.

    Computerized tomography (CT)

    Produces images of the brain from different angles
    Checks for the presence of abnormalities such as narrowed or overstretched blood vessels and history of strokes

    Electroencephalogram (EEG)

    Records electrical activity in the brain
    Changes in the brain waves indicate epilepsy

    The diagnosis is confirmed with the exclusion of more serious conditions such as stroke, seizures or head injury that produce similar symptoms.