You probably know the feeling of walking into a room and blanking on why you came in.
For most of us, that gap lasts a few seconds. For some people, it stretches on for hours.
On Saturday, June 27, 2026, Katie Couric could not say what month it was.
She thought the year was still 2024 and that Joe Biden was in the White House.
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She had spent the morning at a farmers market in Aspen, Colorado, before heading to the Aspen Ideas Festival. She had already moderated two public panels there earlier in the week, and she has no memory of them.
Her husband, John Molner, first wondered about altitude or dehydration. Doctors ran her through a stroke workup. When it came back clear, they gave her the name for what had happened.
The journalist later described the episode on KatieCouric.com. She had experienced transient global amnesia, usually shortened to TGA.
What is transient global amnesia?
TGA is a sudden, temporary failure of the brain to lay down new memories. The person stays awake, knows who they are and can hold a conversation. But nothing new sticks for a few hours.
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Many patients ask the same question over and over, because every answer slips away as soon as they hear it. The attack feels disorienting from the inside, and terrifying for the family watching it.
The condition is rare but not vanishingly so.
American Family Physician puts the overall rate at three to eight cases per 100,000 people each year.
Older adults are especially affected. In people past 50, the rate climbs to about 24 per 100,000 a year, several times higher than the overall figure.
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Most episodes last under six hours. Almost all resolve within a day.
The triggers doctors see most often
An attack rarely comes out of nowhere. In case series it tends to follow a sharp jolt to the body or the nerves.
According to WebMD, the usual culprits are a sudden plunge into hot or cold water, hard physical exertion, a severe emotional shock, and sexual intercourse.
Doctors also point to the Valsalva maneuver, meaning a hard strain against a closed throat. Think heavy lifting or straining on the toilet. Why these events set the brain off is still debated.
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How doctors tell it apart from a stroke
The frightening part for a family is that TGA looks a lot like a stroke in the first minutes. Sudden confusion. Repeated questions. A loved one who cannot remember what day it is.
But the pattern is different. In a classic stroke, the brain also loses some physical function. A drooping face, a weak arm, slurred speech, blurred vision, or trouble walking.
In TGA, memory is the only thing missing. The rest of the person is intact.
That is why TGA is a diagnosis of exclusion. According to the Cleveland Clinic, there is no specific test for it.
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Doctors must first rule out stroke, seizure and head injury in the emergency room before they can land on TGA. Sudden memory loss in you or someone next to you is a 911 call every time.
The outlook is usually excellent
Despite how terrifying the hours feel, TGA has what neurologists call a benign course. Most people have one episode in their lifetime and never go through it again.
The window of the attack itself usually stays blank forever. But the ability to form new memories comes back, and research shows no raised risk of dementia or stroke afterward.
Published recurrence rates run between about 3 and 24 percent across different studies.
This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.