Everyone's familiar with déjà vu - everyone would have experienced it at some stage in your life. It's a disconcerting flash of recognition of something you know you've never seen before, yet still feels all too familiar. Less people know about this term's sister, jamais vu: but it's a great descriptor for another weird mind trick that's just as trippy to experience.
Just as déjà vu is a borrowed French term meaning 'already seen', jamais vu means 'never seen'. It refers to a moment where you fail to recognise a person, place, situation or word that you know is familiar.
While this neurological phenomenon might sound a little less relatable than its more well-known counterpart, there's one example of it that most people have experienced at one time or another. Try this: pick any word on this page, say it over and over and just keep repeating it until you start to doubt that it's actually a real word. That's an example of jamais vu right there.
In more extreme examples, jamais vu can be brought on by intoxication or various disorders, and can lead to sufferers believing friends or family are actually imposters or fakes. This phenomenon can also be brought on by epileptic seizures.
The lesser version of this is known as 'presque vu', or 'almost seen', which is really just a catchier term for having something on the tip of your tongue but not quite being able to remember it.
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