Definition. Transient global amnesia is a sudden, temporary episode of memory loss that can't be attributed to a more common neurological condition, such as epilepsy or stroke.During an episode of transient global amnesia, your recall of recent events simply vanishes, so you can't remember where you are or how you got there.In addition, you may not remember anything about what's happening in the here and now.ut that doesn't make your memory loss less disturbing. Fortunately, transient global amnesia is rare, seemingly harmless and unlikely to happen again. Episodes are usually short-lived, and afterward your memory is fine. 1  Symptoms.