Symptoms of transient global amnesia
What are the clinical characteristics of transient global amnesia?
Patients develop a sudden, isolated amnestic syndrome without structural brain abnormalities (anterograde and retrograde amnesia), which usually has a duration of 12 to 24 hours.
Afterward, patients will not remember the episode because they are unable to encode new memories during it. Working memory is normal during the episode.
On positron emission tomography (PET) or single-photon emission computed tomography (SPECT), bilateral temporal hypoperfusion can be demonstrated.
The cause of this benign syndrome remains unknown.
However, because it occurs more often in migraineurs, it could be a migraine equivalent.
It is also more likely in those with epilepsy, patients at risk for transient ischemic attack, and during exercise. Risk of recurrence is low but higher than in the general population.
