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Déjà vu (
French pronunciation: [deʒa vy] ( listen),
literally "already seen") is the experience of feeling sure that one
has already witnessed or experienced a current situation, even though
the exact circumstances of the prior encounter are uncertain and were
perhaps imagined. 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", "weirdness", or what
Sigmund Freud calls "the
uncanny".
The "previous" experience is most frequently attributed to a dream,
although in some cases there is a firm sense that the experience has
genuinely happened in the past.
[1]
Scientific research
The psychologist
Edward B. Titchener in his book
A Textbook of Psychology
(1928), wrote that déjà vu is caused by a person getting a brief
glimpse of an object or situation prior to full conscious perception,
resulting in a false sense of familiarity.
[2] The explanation that has mostly been accepted of déjà vu is not that it is an act of "
precognition" or "
prophecy", but rather that it is an anomaly of memory, giving the false impression that an experience is "being recalled".
[3][4]
This explanation is supported by the fact that the sense of
"recollection" at the time is strong in most cases, but that the
circumstances of the "previous" experience (when, where, and how the
earlier experience occurred) are quite uncertain or believed to be
impossible. Likewise, as time passes, subjects can exhibit a strong
recollection of having the "unsettling" experience of déjà vu itself,
but little or no recollection of the specifics of the event(s) or
circumstance(s) they were "remembering" when they had the déjà vu
experience. In particular, this may result from an overlap between the
neurological systems responsible for
short-term memory and those responsible for
long-term memory
(events which are perceived as being in the past). The events would be
stored into memory before the conscious part of the brain even receives
the information and processes it.
[citation needed]
Links with disorders
Early researchers tried to establish a link between déjà vu and serious psychopathology such as
schizophrenia,
anxiety, and
dissociative identity disorder,
and failed to find the experience of some diagnostic value. There does
not seem to be a special association between déjà vu and schizophrenia
or other psychiatric conditions.
[5] The strongest pathological association of déjà vu is with
temporal lobe epilepsy.
[6][7] This correlation has led some researchers to speculate that the experience of déjà vu is possibly a
neurological anomaly related to improper electrical discharge in the brain. As most people suffer a mild (i.e. non-pathological)
epileptic episode regularly (e.g. a
hypnagogic jerk,
the sudden "jolt" that frequently, but not always, occurs just prior to
falling asleep) it is conjectured that a similar (mild) neurological
aberration occurs in the experience of déjà vu, resulting in an
erroneous sensation of memory.
Pharmacology
Certain drugs increase the chances of déjà vu occurring in the user.
Some pharmaceutical drugs, when taken together, have also been
implicated in the cause of déjà vu. Taiminen and Jääskeläinen (2001)
[8]
reported the case of an otherwise healthy male who started experiencing
intense and recurrent sensations of déjà vu upon taking the drugs
amantadine and
phenylpropanolamine
together to relieve flu symptoms. He found the experience so
interesting that he completed the full course of his treatment and
reported it to the psychologists to write up as a case study. Due to the
dopaminergic
action of the drugs and previous findings from electrode stimulation of
the brain (e.g. Bancaud, Brunet-Bourgin, Chauvel, & Halgren, 1994),
[9]
Taiminen and Jääskeläinen speculate that déjà vu occurs as a result of
hyperdopaminergic action in the mesial temporal areas of the brain.
Memory-based explanations
The similarity between a déjà-vu-eliciting stimulus and an existing, but different, memory trace may lead to the sensation.
[5][10]
Thus, encountering something which evokes the implicit associations of
an experience or sensation that cannot be remembered may lead to déjà
vu. In an effort to experimentally reproduce the sensation, Banister and
Zangwill (1941)
[11][12] used
hypnosis
to give participants posthypnotic amnesia for material they had already
seen. When this was later re-encountered, the restricted activation
caused thereafter by the posthypnotic amnesia resulted in three of the
10 participants reporting what the authors termed "paramnesias".
Memory-based explanations may lead to the development of a number of
non-invasive experimental methods by which a long sought-after analogue
of déjà vu can be reliably produced that would allow it to be tested
under well-controlled experimental conditions. Cleary
[10]
suggests that déjà vu may be a form of familiarity-based recognition
(recognition that is based on a feeling of familiarity with a situation)
and that laboratory methods of probing familiarity-based recognition
hold promise for probing déjà vu in laboratory settings. Another
possible explanation for the phenomenon of déjà vu is the occurrence of "
cryptomnesia",
which is where information learned is forgotten but nevertheless stored
in the brain, and similar occurrences invoke the contained knowledge,
leading to a feeling of familiarity because of the situation, event or
emotional/vocal content, known as "déjà vu".
Parapsychology
Some
parapsychologists have advocated some unorthodox interpretations of déjà vu.
Ian Stevenson and a minority of other researchers have written that some cases of déjà vu might be explained on the basis of
reincarnation.
[13][14] Anthony Peake has written that déjà vu experiences occur as people are living their lives not for the first time but at least the second.
[15]
Related phenomena
Jamais vu
Jamais vu (from French, meaning "never seen") is a term in psychology
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
aphasia,
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 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 depersonalisation (or
surreality) feelings.
Times Online reports (see
semantic satiation):
Chris Moulin, of the University of Leeds,
asked 95 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 the 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.[16]
Presque vu (Tip of the tongue)
Déjà vu is similar to, but distinct from, the phenomenon called
tip of the tongue,
a situation when someone cannot recall a familiar word or name, 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 my tongue".
Déjà entendu
Déjà entendu, (literally "already heard") is the experience of
feeling sure that one has already heard something, even though the
exact details are uncertain and were perhaps imagined.
[17][18]
Reja vu
The feeling something that has happened or is happening will happen
again, possibly in the near future, possibly in the distant future.
In popular culture
Film
Déjà vu provides a plot point in
The Matrix, a 1999
science fiction-
action film written and directed by
Larry and Andy Wachowski. The protagonist,
Neo,
glances at a black cat and comments that he has just experienced déjà
vu. Those with a knowledge of 'The Matrix' and its internal workings
state that déjà vu means something within the Matrix was altered from
its prior state and is referred to as a "
glitch".
The 2006 science fiction film
Déjà Vu
revolves around a US federal law enforcement officer using an
instrument called Snowhite to view the past 4 and a half days of
anywhere in the world (limited radius as permissible by the program) in
order to solve a murder and a terrorist bomb attack on a ferry that was
being boarded by about 500 citizens and military members.
Television
Déjà Vu was the third episode of the second season of
Monty Python's Flying Circus, a British comedy program.
Michael Palin plays a television host with the problem.
[19]
The concept is explored in the episode 119 of
Garfield and Friends in the Orson's Farm segment.
The final episode of season 1 of
Charmed, called "Déjà Vu All Over Again" sees
Phoebe Halliwell reliving the same day over and over again at the hands of a demon named Tempus.
[20]
Déjà Vu is also a recurring plot element on
Fringe.
In the Season One episode, "The Road Not Taken", Olivia described the
experience of déjà vu to Walter after she briefly experienced an
alternate reality as the result of being a Cortexiphan subject. In the
Season Two episode "White Tulip", Olivia experiences déjà vu while
investigating the apartment of a time traveler who reset the timeline.
Déjà Vu is also a plot element in the "Mystery Episode" of the
television series Supernatural where Sam Winchester wakes up in the same
day as a result of being trapped in a time loop.
Radio
Déjà Vu is a 2009
radio play by
Alexis Zegerman in French and English co-produced by
BBC Radio 4 and
ARTE Radio.
Theatre
Déjà Vu is a 1991
stage play by
John Osborne.
Music
Below is a list of artists who have referenced Déjà Vu in their work.
See also
References
- ^ Berrios, G.E. (1995). "Déjà vu and other disorders of memory during the nineteenth century". Comprehensive Psychiatry 36: 123–129.
- ^ Titchener, E. B. (1928). A textbook of psychology. New York: Macmillan
- ^ "The Meaning of Déjà Vu", Eli Marcovitz, M.D. (1952). Psychoanalytic Quarterly, vol. 21, pages: 481-489
- ^ The déjà vu experience, Alan S. Brown, Psychology Press, (2004), ISBN 0-203-48544-0, Introduction, page 1
- ^ a b Brown, Alan S. (2004). The Déjà Vu Experience. Psychology Press. ISBN 1841690759.
- ^ Neurology Channel
- ^ Howstuffworks "What is déjà vu?"
- ^ Taiminen,
T.; Jääskeläinen, S. (2001). "Intense and recurrent déjà vu experiences
related to amantadine and phenylpropanolamine in a healthy male". Journal of Clinical Neuroscience 8 (5): 460–462. doi:10.1054/jocn.2000.0810. PMID 11535020. edit
- ^ Bancaud,
J.; Brunet-Bourgin; Chauvel; Halgren (1994). "Anatomical origin of déjà
vu and vivid 'memories' in human temporal lobe epilepsy". Brain : a journal of neurology 117 (1): 71–90. PMID 8149215. edit
- ^ a b Cleary, Anne M. (2008). "Recognition memory, familiarity and déjà vu experiences". Current Directions in Psychological Science 17 (5): 353–357. doi:10.1111/j.1467-8721.2008.00605.x.
- ^ Banister H, Zangwill OL (1941). "Experimentally induced olfactory paramnesia". British Journal of Psychology 32: 155–175.
- ^ Banister H, Zangwill OL (1941). "Experimentally induced visual paramnesias". British Journal of Psychology 32: 30–51.
- ^ Fisher, J. (1984). The case for reincarnation. New York: Bantam Books.
- ^ Stevenson, I. (1987). Children who remember past lives. Charlottesville, VA: University Press of Virginia.
- ^ Anthony Peake Is There Life After Death? The Extraordinary Science of What Happens When We Die Arcturus Publishing Limited, 2012 ISBN 184837299X
- ^ Ahuja, Anjana (2006-07-24). "Doctor, I've got this little lump on my arm . . . Relax, that tells me everything". London: Times Online. Retrieved 2010-05-01.
- ^ Grinnel, Renée (2008), Déjà Entendu, PsychCentral, retrieved 04-10-2011
- ^ Mental Status Examination Rapid Record Form
- ^ "Monty Python's Flying Circus: Just the Words - Episode 16". Ibras.dk. Retrieved 2012-03-23.
- ^ http://www.imdb.com/title/tt0539356/
Further reading
- "What is déjà vu?". Psychology Today. 2010-01-05.
- Draaisma, Douwe (2004). Why life speeds up as you get older. Cambridge University Press. ISBN 0521691990.
- Hughlinks-Jackson, J. (1888). "A particular variety of epilepsy "intellectual aura", one case with symptoms of organic brain disease". Brain 11 (2): 179–207. doi:10.1093/brain/11.2.179.
- Carey, Benedict (2004-09-14). "Déjà Vu: If It All Seems Familiar, There May Be a Reason". New York Times. Retrieved 2010-05-01.
- Ratliff, Evan (2006-07-02). "Déjà Vu, Again and Again". New York Times. Retrieved 2010-05-01.
- "When déjà vu is more than just an odd feeling". The Ottawa Citizen. 2006-02-20.
- "UGH! I Just Got the Creepiest Feeling That I Have Been Here Before: Déjà vu and the Brain, Consciousness and Self". Neurobiology and Behavior. 1998.
- "The Tease of Memory". The Chronicle of Higher Education. 2004-07-23.
- "The Psychology Of Deja Vu". Science Daily. 2008-11-19.
- Herbert, Wray (2008-10-23). "And I feel like I've been here before". Psychological Science.
- McHugh TJ, Jones MW, Quinn JJ et al
(July 2007). "Dentate gyrus NMDA receptors mediate rapid pattern
separation in the hippocampal network". Science 317 (5834): 94–9. doi:10.1126/science.1140263. PMID 17556551.
External links
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See Also:
First
came the heterodyne. The principle of "beats" or difference tones
between simultaneous audio pitches was well known since antiquity, but
Reginald Fessenden in 1901 was the first to apply the principle to radio
transmissions [3]. Originally both radio frequencies were to be
transmitted, received with two antennas, and combined in a detector.
Later a local oscillator was substituted for one of the
transmitter-receiver combinations and the heterodyne as we know it was
born. Fessenden himself coined the term, from the Greek heteros (other)
and dynamis (force).Who Invented the Superheterodyne?