Jamais vu

In psychology, jamais vu (/ˈʒæmeɪ ˈvuː/; French pronunciation: ​[ʒa.mɛ.vy]) from French, meaning "never seen") is the phenomenon of experiencing a situation that one recognizes in some fashion, but that, nonetheless, seems very unfamiliar.

Often described as the opposite of déjà vu, jamais vu involves a sense of eeriness and the observer's impression of seeing the situation for the first time, despite rationally knowing that he or she has been in the situation before. Jamais vu is sometimes associated with certain types of aphasia, amnesia, and epilepsy.

Jamais vu is most commonly experienced when a person momentarily does not recognise a word or, less commonly, a person or place, that she or he knows. This can be achieved by anyone by repeatedly writing or saying a specific word out loud. After a few seconds one will often, despite knowing that it is a real word, feel as if "there's no way it is an actual word".

The phenomenon is often grouped with déjà vu and presque vu, or tip of the tongue.

Theoretically, as seen below, a jamais vu feeling in a sufferer of a delirious disorder or intoxication could result in a delirious explanation of it, such as in Capgras delusion, in which the patient takes a person known by him or her for a false double or impostor. If the impostor is himself, the clinical setting would be the same as the one described as depersonalisation; hence, jamais vus of oneself or of the very "reality of reality" are termed depersonalization and derealization, respectively.

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