October 01, 2021

Sudden but temporary memory loss. Is it a stroke?

Q: A few weeks ago, my wife suddenly couldn't remember where she was and kept forgetting after I told her. We went to the emergency room, where the doctors told us it was something called transient global amnesia and it would go away in a day or less. It did, but I'm still worried about her. Did she have a stroke?

A: Watching a loved one lose their memory — even if only temporarily — can be a distressing experience. Because serious conditions such as a stroke or seizure can cause memory loss, always seek immediate medical attention if experiencing these symptoms. You did the right thing in going to the emergency room so that doctors could rule out these other conditions.

People experiencing an episode of transient global amnesia (TGA) can't form new memories and may not remember recent events. They typically cannot remember where they are or how they got there. They also often repeat the same questions ("How did we get here?") because they can't remember the answers they've just been given. However, they still remember their identities and people they know well. Problems with speaking and muscle control or coordination (ataxia) are not usually present, which can differentiate an episode of TGA from something more serious, such as a stroke.

There are theories as to what causes TGA but no definitive answer. People over the age of 50 and those with a history of migraine are probably at higher risk. Certain events — such as extreme positive or negative emotional stress, immersion in cold or hot water, sexual intercourse, or intense physical activity — are thought to be triggers. Because the cause is unclear, there's no real way to prevent an episode from occurring.

TGA isn't considered harmful and usually goes away after a few hours. While it's possible that your wife may experience another episode of TGA, it's rare to have...