Try this: write your own name on a piece of paper. Now write it again. And again, 10, 20, 30 times in a row.
Somewhere in the middle of that list, there's a decent chance something strange will happen. The letters will start to look off. The word will stop reading like a word and look more like a string of marks someone has asked you to copy out. For a second or two, your own name might feel as if it belongs to somebody else.
That flicker of unreality has a name, and it's the mirror image of a much more famous one. We all know déjà vu, the eerie feeling that a brand-new moment has happened before. Its opposite gets far less attention: a familiar face, word or place suddenly strikes you as wrong, alien or unreal, even though you know it isn't. Psychologists call it jamais vu, French for "never seen."
It shows up in small, strange ways. Musicians describe losing their place in a passage they've played hundreds of times. Neuropsychologist Akira O'Connor of the University of St Andrews, one of the scientists who has spent the most time studying it, once had it happen while driving. He had to pull over onto the hard shoulder because the pedals and steering wheel had briefly stopped feeling like his.
Most people experience déjà vu at some point, but jamais vu is far rarer, which makes it hard to study. So O'Connor and his long-time collaborator Chris Moulin, a cognitive neuropsychologist at Université Grenoble Alpes, set out to trigger it on demand in a lab, using nothing but a pen and paper. In 2023, their team won an Ig Nobel Prize for the work. The satirical award honors research that "first makes people laugh, then makes them think."
Their method was almost embarrassingly simple. Ninety-four university students were asked to copy out the same word over and over, from common words like "door" to unusual ones like "sward," and to stop whenever it started to feel wrong. About 70 percent did stop, typically after about a minute, or roughly 33 repetitions. In a second version that used only the word "the," 55 percent of people stopped after just 27 repetitions.
The participants' own descriptions are the best part of the study. "They lose their meaning the more you look at them," one said. Another wrote: "It doesn't seem right, almost looks like it's not really a word, but someone's tricked me into thinking it is." One participant said the feeling had also struck during exams: even after spelling a word like "appetite" correctly, they kept looking at it again and again, suspecting it might be wrong.
The leading explanation is something psychologists call satiation. The idea is that when you look at a word, face or object intensely and repeatedly, the brain's representation of it becomes temporarily overloaded and stops making sense.
It's an old idea that had to be rediscovered. O'Connor and Moulin spent close to 15 years developing what they thought was a new experiment, only to find that the psychologist Margaret Floy Washburn and her student Elizabeth Severance had published something almost identical in 1907. They described "the loss of associative power in words after long fixation." Stare at a printed word for around three minutes, they found, and it starts to come apart.
For a long time, satiation was assumed to be a top-down process, a glitch in the brain's language and meaning systems, high up the chain of thinking. A 2024 study complicates that picture. Researchers built a deep-learning model designed to mimic the visual cortex, the brain region that processes raw shapes before anything like meaning enters the picture. They fed the model repeating visual patterns and tracked how well it could classify them over time.
Its accuracy rose, peaked and then, with nothing else changed, began to fall, simply from looking. The team concluded that satiation may be a "bottom-up process" rooted in basic visual processing, rather than something imposed from higher up.
If that holds true in living brains, jamais vu may not start with your brain losing track of what a word means. It may start with your visual system quietly giving up on what a word even is.
Researchers have only scratched the surface. Nobody yet knows, for example, how satiation and jamais vu relate to the verbal transformation effect, in which a word repeated aloud seems to change into a different word.
So the next time your own name looks as if a stranger wrote it, you're not imagining things. You're watching your brain do something scientists still don't fully understand.