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 most commonly experienced when a person momentarily does not recognise a word, person, or place that he or she already knows, and it is more rarely experienced with people and places.
The TimesOnline reports:
- Chris Moulin, of Leeds University, asked 92 volunteers to write out "door" 30 times in 60 seconds. At the International Conference on Memory in Sydney last week he reported that 68 percent of volunteers showed symptoms of jamais vu, such as beginning to doubt that "door" was a real word. Dr Moulin believes that a similar brain fatigue underlies a phenomenon observed in some schizophrenia patients: that a familiar person has been replaced by an impostor. Dr Moulin suggests they could be suffering from chronic jamais vu.
Related phenomena 
- Déjà vu: remembering having seen something unexperienced before. In French, this literally means 'already seen', though in usage it is basically equivalent to déjà vécu, "already lived."
- Presque vu: almost, but not quite, remembering something. It is also referred to as tip of the tongue.
See also 
- Semantic satiation
- Capgras delusion (the delusion that a friend or relative is an impostor)
- Depersonalization disorder
- Health & Medical News - Is it really you or jamais vu? - 19 July 2006
- Doctor, I've got this little lump on my arm . . . Relax, that tells me everything - Comment - Times Online
-  "Epilepsy and seizure information for patients and health professionals — Simple Partial Seizures", retrieved 2011-09-08