Transient Global Amnesia

What is Transient Global Amnesia?

Transient Global Amnesia (TGA) refers to a sudden episode of memory loss. As suggested by its name, an episode of TGA is temporary and typically lasts only for a few hours, though in rare cases, may last up to 24 hours. Individuals experiencing an episode of TGA will have normal cognition, retain their personal identity and preserve their ability to carry out complex tasks such as driving. However,  they will not be able to formulate or recall memories. For example, individuals may know who they are and recognise loved ones, but not remember what they were doing and where they were. This is usually accompanied by confusion and disorientation as well. Though frightening and potentially psychologically traumatic, TGA does not have any serious, direct complications and will usually resolve on its own.

What does having TGA feel like?

If you have TGA, you will likely experience a sudden onset of temporary memory loss. Other symptoms of TGA include: 

  • Confusion and disorientation 
  • Repeated questioning of transpired events 
  • Gradual return of memory 
  • No evidence of head/ brain injuries 
  • No evidence of epilepsy or seizures during TGA episode 

What are the causes and risk factors of TGA?

Currently, there are no known underlying causes of TGA. However, some commonly reported triggers include: 

  • Emotional or psychological distress 
  • Sudden submersion in hot or cold water 
  • Sexual intercourse
  • Vigorous physical activity 
  • Medical procedures (endoscopy, angiography) 
  • Exposure to high altitudes 
  • A Valsalva maneuver (a breathing method that helps to slow down one’s heart rate) 

As of now, the clearest risk factor of TGA is age. Individuals, particularly females, over the age of 50 have a higher risk of experiencing an episode of TGA. There have also been reports of associations between migraines and TGA, whereby those with a history of migraines may be at a significantly higher risk of TGA than those without [1]. 

How is TGA diagnosed?

Medical examination. To diagnose your TGA, your doctor will have to conduct a thorough medical examination. Your doctor may ask you about your symptoms and medical history as well.

Neuroimaging. Additionally, your doctor may also make use of neuroimaging in the form of CT and MRI scans to rule out other conditions which may mimic the symptoms of TGA, such as brain ischemia, whereby there is insufficient blood flow to the brain to meet metabolic demands.

How do I prevent myself from getting TGA?

As the definitive cause of TGA is unknown and the rate of recurrence is low at about 2.9 to 26.3% [2], there are no concrete ways to prevent the condition.

How is TGA treated?

There are no specific treatments for TGA as symptoms typically resolve on their own within 24 hours. However, if you have experienced any of the symptoms listed above, it is wise to consult a doctor immediately to rule out the possibility of any other underlying medical conditions which may require urgent medical attention. 

  1. Montagna, P., Cerullo, A., & Cortelli, P. (2000, February 16). Transient global amnesia occurring as migraine aura. Institute of Clinical Neurology, University of Bologna.
  2. Spiegel, D. R., Smith, J., Wade, R. R., Cherukuru, N., Ursani, A., Dobruskina, Y., Crist, T., Busch, R. F., Dhanani, R. M., & Dreyer, N. (2017). Transient global amnesia: current perspectives. Neuropsychiatric Disease and Treatment, Volume 13, 2691–2703. 
  3. Transient global amnesia            | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program. (2016, December 19). Nih.Gov; NIH.