Feb 8, 2010

The Deja Experience

Déjà vu has been quite a word now and everywhere you go, majority knows the meaning of such word. Usually this word is associated of different buzz and was foretold to be entailed with something strange. Even though this word is mostly used, the meaning seems distant and vague from reality. Usually, one person sometimes will or will not remember any of this. And this word has been noted or related to some clinical behavior disorders which sometimes people prevent from thinking. Generally, people think a lot different way especially toward others if they exhibit or talk about unusual things.

Anyways, I came across to this study due to my boredom since I don’t have much to do lately because of the transition stuffs that I will be having, and got amazed of it. I’m going to relate to you some idyllically articles that I have read for this topic. People believed that everybody experiences déjà stuffs but sometimes could not be remembered since the obscurity of such things is quite normal like what a dream exist (unless of course its horrifying). The Déjà experience has been related and deciphered to three different types.

Déjà Vu (Promnesia)

This is the experience and feeling sure of that you had witnessed or experienced a new situation that had just happened. An individual usually feels as though an event has already happened or has happened in the recent past, although the exact circumstances of the previous encounter are uncertain. The term was coined by a French psychic researcher, Emile Boirac and stated in her book that this 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.
The experience of déjà vu seems to be quite common among adults and children alike. References to the experience of déjà vu are also found in literature of the past, indicating it is not a new phenomenon. It has been extremely difficult to evoke the déjà vu experience in laboratory settings, therefore making it a subject of few empirical studies. Certain researchers claim to have found ways to recreate this sensation using hypnosis. However, the subject of hypnosis is indeed controversial among some circles, and such data would demand proof that hypnosis is possible as per the manner the study implies. Anyways, Déjà vu is broken down to three different experiences. This was taken from the Mentalhelp.com

• Déjà vécu (‘already experienced’ or ‘already lived through’)
“We have all some experience of a feeling, that comes over us occasionally, of what we are saying and doing having been said and done before, in a remote time—of our having been surrounded, dim ages ago, by the same faces, objects, and circumstances—of our knowing perfectly what will be said next, as if we suddenly remember it!” (chapter 39).
That was a fairly well-known quite from David Copperfield which introduces the meaning of Déjà vecu. A number of surveys have shown that about two-thirds of the American adult population claim to have had such or similar experiences (e.g., Fox, 1992). Moreover, surveys have indicated that such experiences tend to occur more frequently and possibly more intensely when the respondents were young, say between ages 15 to 25 (e.g., MacCready & Greeley, 1976). In addition, such experiences are frequently, if not always, connected with very banal events. They are so striking, though, that they are often clearly remembered for years following their occurrence. Anyone having had such experiences knows that they normally involve more sense modalities than just sight. As in the Dickens quotation, they can easily involve hearing, tasting, touch and/or proprioceptive perceptions as well. This is why referring to such experiences as simply déjà vu is inadequate.

Another feature of déjà vécu that most would agree with is the amazing detail involved. When you are in the midst of such an occurrence, you are conscious that everything conforms to your ‘memory’ of it. This is why explanations which suggest that the person has read about or experienced something similar in the past cannot be valid. Moreover, this is why explanations based on reincarnation and past lives can also be ruled out. A typical déjà vécu experience can easily involve clothing or even a PC, but styles of clothing change practically every year and it is rather unlikely that someone had a PC on his or her desk in a previous life (this objection to the reincarnation explanation was pointed out already in 1845 by von Feuchtersleben)! If incidences of déjà vécu can be taken as being real, our notions of causality may have to be revised in some ways. It does not seem to be difficult, though, for modern physicists to entertain notions of time loops (Deutsch & Lockwood, 1994), tachyons (particles that can travel backwards in time – Chester, 1978) and multiple universes (DeWitt & Graham, 1973). That our unconscious would then be able to avail itself of such anomalies and present us with precognitive knowledge via visions and dreams (Funkhouser, 1983b; Rybach & Sweitzer, 1988) is then not as farfetched as it might seem at first glance

• Déjà senti (‘already felt’)

To introduce it, here is a quote from a 1888 paper by Dr. John Hughlings Jackson, one of the foremost pioneers of modern neurology. In the words of one of his patients, a medical doctor suffering from what has come to be known as temporal lobe or psychomotor epilepsy, he wrote:
“What is occupying the attention is what has occupied it before, and indeed has been familiar, but has been for a time forgotten, and now is recovered with a slight sense of satisfaction as if it had been sought for... At the same time, or... more accurately in immediate sequence, I am dimly aware that the recollection is fictitious and my state abnormal. The recollection is always started by another person’s voice, or by my own verbalized thought, or by what I am reading and mentally verbalize; and I think that during the abnormal state I generally verbalize some such phrase of simple recognition as ‘Oh yes—I see’, ‘Of course—I remember’, &c., but a minute or two later I can recollect neither the words nor the verbalized thought which gave rise to the recollection. I only find strongly that they resemble what I have felt before under similar abnormal conditions.”
This state, which sometimes appears in the aura of temporal lobe epilepsy attacks, Jackson termed ‘reminiscence’ and believe could be best termed déjà senti. Three features are evident from this description, however, that distinguish it from déjà vécu:
  • it is primarily or even exclusively a mental happening;
  • there are no precognitive aspects in which the person feels he or she knows in advance what will be said or done; and
  • it seldom or never remains in the afflicted person’s memory afterwards.

• Déjà visité (‘already visited’)

There is another phenomenon which is also often confused with déjà vécu. It seems to occur more rarely and is an experience in which a person visits a new locality and nevertheless feels it to be familiar. He or she seems to know their way around. C. G. Jung published an interesting account of it in his paper on synchronicity (Jung, 1966). To distinguish it from déjà vécu, it is important to ask whether it was purely the place and location of inanimate buildings and/or objects that were familiar, or did the situation that the person was in also play a role. Déjà visité has to do with geography, with the three spatial dimensions of height, width and depth, while déjà vécu has to do more with temporal occurrences and processes. Déjà visité can be explained in several ways. It may be that the person once read a detailed account of the place and has subsequently forgotten it. This happened to Nathaniel Hawthorne on a visit he made to the ruins of a castle in England (Hawthorne, 1863). He ‘recognized’ the place but didn’t know how or why. Only later was he able to trace it to a piece written two hundred years earlier by Alexander Pope about it. The incident of déjà visité described by Sir Walter Scott in his 1815 book, Guy Mannering, is also based on this hypothesis. Reincarnation might also offer a way of explaining some instances of déjà visité.

A third possibility is so-called ‘out-of-the-body’ experiences (see Chap. 8, Chari) in which a person is apparently able to travel abroad, leaving his or her body behind. It is possible that mixed versions of these three forms of ‘déjà’ experience may occur. There are also several other phenomena which resemble these in various ways, but space does not permit going into them here. Those wishing to know more and explore the various aspects of déjà phenomena more deeply are referred to the excellent overviews in Neppe (1983) and Brown (2004).

Jamais vu  (Never Seen)

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 doesn't recognize a word, person, or place that he/she already knows. Jamais vu is sometimes associated with certain types of amnesia and epilepsy. With seizures, jamais vu can surface as an aura due to a partial seizure disorder that originates from the temporal lobe of the brain. It also can occur as a migraine aura.

The first scientific study of jamais vu, the reverse of déjà vu, has shown that the experience exists and can be induced, an international memory conference has heard. Jamais vu literally means "never seen" and describes the sense of unfamiliarity in the face of very familiar things or situations, says UK researcher Dr Chris Moulin of the University of Leeds.

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 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.

"If you stare at a word, for instance, it loses its meaning," says Moulin, who adds that an estimated 60% of people have experienced jamais vu. He presented his research for the first time at the 4th International Conference on Memory in Sydney.

Musicians can get [jamais vu] in the middle of playing a familiar passage. It's the sensation where you wake up in the morning and turn to the person next to you and feel that they're a stranger," says Moulin.

It can also occur when you look at a face for too long and it begins to look strange, or when you're in a familiar place but think 'I don't know where I am', for a brief, fleeting moment."

Jamais vu was first recognized about 100 years ago when it was regarded as something of a "gentleman's intrigue", Moulin says. But it has never been systematically studied in a laboratory until now.

Brain Fatigue

Moulin says his study shows it's possible to induce jamais vu by what's known as semantic satiation, which occurs when the brain becomes fatigued in a specific way. He asked 92 subjects to write common words such as "door" 30 times in 60 seconds. When they were later asked to describe their experiences, 68% showed signs of jamais vu.

For example, after writing "door" over and over again some participants reported that "it looked like I was spelling something else", it "sounded like a made-up word" and "I began to doubt that I was writing the correct word for the meaning". Some thought they had been tricked into thinking it was the right word for a door. "If you look at something for long enough the mind gets tired and it loses it's meaning," Moulin says.

Moulin says studying jamais vu will help researchers better understand psychiatric disorders like schizophrenia or Capgras delusion, where people believe someone they know very well has been replaced by an impostor. "It suggests that this is the normal process that might go wrong in these people, they might just have chronic jamais vu," Moulin says. His latest research aims to induce jamais vu and monitor what actually goes on in the brain using neural imaging.

Presque Vu (Tip of Tongue)

The tip of the tongue (TOT or Tot or Presque vu, from the French for "almost seen") phenomenon is an instance of knowing something that cannot immediately be recalled. TOT is an experience with memory recollection involving difficulty retrieving a well-known word or familiar name. When experiencing TOT, people feel that the blocked word is on the verge of being recovered. Despite failure in finding the word, people have the feeling that the blocked word is figuratively "on the tip of the tongue." Inaccessibility and the sense of imminence are two key features of an operational definition of TOTs (A.S. Brown, 1991).

TOT research in children has mainly focused on when they begin to experience TOTs and what the experience is like for them (Brown, 1991). Wellman (1977) found evidence that children between kindergarten and third grade (ages 6–9) did experience TOTs, though very rarely. They were able to recall pieces of the target word, words that sound like it or rhymed with it, and long words that included it. Further, they would tell researchers that they knew the word, but were having trouble remembering it. Like adults, they also became uncomfortable and frustrated by the experience. Finally, his findings suggest that TOTs occur more often in third graders (ages 8–9) than they do in kindergarteners and first graders.

More research has been done with TOTs in older adults. In terms of subjective estimates, research has found that older adults report experiencing TOTs about as often as younger adults (Brown, 1991). However, studies by Burke et al. (1991) and Cohen and Faulkner (1986) with more objective measurements received different results. Their participants kept diaries for four weeks, recording their TOT experiences, and young adults were found to experience significantly fewer TOTs than older adults. Other TOT literature has found that older adults remember less information about the target word and bring up fewer related words during the TOT experience and are less active in resolving the TOT experience (Brown, 1991).

One theory of why the tip of the tongue phenomenon occurs comes from Petro Gopych (2001), a professor at the Kharkiv National University. Gopych’s model proposes three stages in word recall process.

• Word node selection
This first stage involves actually selecting which word we are trying to recall. When specifying the word, we identify the learned artificial neural network (ANN) which contains information about the target word, and then activate that part.

• Word retrieval
According to Gopych, free recall exhibits positive and negative outputs randomly in the learned ANN. When trying to recall a specific word, otherwise known as cued recall, the retrieval process depicts a “spike” of these outputs with a fixed part of the true information (specific word). The result of attempts to retrieve the word from the learned ANN is an output of positive and negative units.

• Comparison of patterns
The pattern of outputs determined by the retrieval attempts is compared to a reference pattern from metamemory. If the sample pattern matches the reference pattern, the searching stops because the word that was searched for is recalled. If there is no match, the retrieval process (stage 2) starts over again and a pattern of outputs enters the ANN. This continues until the reference pattern is detected or the process is stopped independently.

Gopych believes that the problem in recalling a specified word comes from a damaged ANN. He suggests that the stored semantic information is damaged or incompletely selected. The severity of the damage determines the power of the TOT.

Gopych’s three stage neural network theory can be used to explain many aspects of TOT including semantic priming, immediate, delay, or eventually full TOT resolution, age dependence in TOTs, recollection of the first letter of the target word, and many more. Using the number of attempts of memory retrieval, the duration of time intervals between successive sets of spikes, and the duration of single neuron spikes, the retrieval chronometry can be determined. Gopych’s theory also supports Tulving’s challenge to the doctrine of concordance.

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