Déjà vu ("already seen") also called paramnesia or promnesia, is the experience of feeling sure that one has witnessed or experienced a new situation previously (an individual feels as though an event has already happened or has happened in the near past), although the exact circumstances of the previous encounter are uncertain. The term was coined by a French psychic researcher, Émile Boirac (1851–1917) in his book "L'Avenir des sciences psychiques" ("The Future of Psychic Sciences"), which expanded upon an essay he wrote while an undergraduate. The experience of déjà vu is usually accompanied by a compelling sense of familiarity, and also a sense of "eeriness," "strangeness," or "weirdness." The "previous" experience is most frequently attributed to a dream, although in some cases there is a firm sense that the experience "genuinely happened" in the past.It has been extremely difficult to evoke the déjà vu experience in laboratory settings, therefore making it a subject of few empirical studies. Recently, researchers have found ways to recreate this sensation using hypnosis.Some believe déjà vu is the memory of dreams.In this case, déjà vu might be a memory of a forgotten dream with elements in common with the current waking experience.This may be similar to another phenomenon known as déjà rêvé, or "already dreamed."Also, persons with only one eye still report experiencing déjà vu or déjà vécu (a rare disorder of memory, similar to persistent déjà vu).
Those believing in reincarnation theorize that déjà vu is caused by fragments of past-life memories being jarred to the surface of the mind by familiar surroundings or people. Others theorize that the phenomenon is caused by astral projection, or out-of-body experiences (OBEs), where it is possible that individuals have visited places while in their astral bodies during sleep. The sensation may also be interpreted as connected to the fulfillment of a condition as seen or felt in a premonition.
$_<>( Jamais vu )<>_$
Jamais vu is a term in psychology (from French, meaning "never seen") which is used to describe any familiar situation which is not recognized by the observer.
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 more commonly explained as when a person momentarily does not recognize a word, person, or place that they already know.
Jamais vu is sometimes associated with certain types of amnesia and epilepsy.
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 the Capgras delusion, in which the patient takes a person known by him/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 depersonalisation (or irreality) feelings.
$_<>( Tip of Tongue {Presque vu} )<>_$
Déjà vu is similar to, but distinct from, the phenomenon called tip of the tongue which is when one cannot recall a familiar word or name or situation, but with effort one eventually recalls the elusive memory. In contrast, déjà vu is a feeling that the present situation has occurred before, but the details are elusive because the situation never happened before. Presque vu (from French, meaning "almost seen") is the sensation of being on the brink of an epiphany. Often very disorienting and distracting, presque vu rarely leads to an actual breakthrough. Frequently, one experiencing presque vu will say that they have something "on the tip of their tongue."
Presque vu is often cited by people who suffer from epilepsy or other seizure-related brain conditions, such as temporal lobe lability.
$_<>( L'esprit de l'escalier )<>_$
L'esprit de l'escalier (from French, "staircase wit") is remembering something when it is too late (for example, a clever comeback to a remark, thought of after the conversation has ended).
