<em>When  déjà vu becomes unbearable , Jan. 30, 2006
Courtesy the University of Leeds and <a href="http://www.world-science.net/othernews/060130_dejavufrm.htm" target="new">World Science</a> staff</em>

Many of us have experienced déjà vu—that tingly, yet unsettling feeling that we are going through something we’ve experienced before, even though we haven’t.

But for some of us, it becomes pathological.

One man had it so badly that he stopped watching TV because everything seemed to be a repeat, even the news, recalls psychologist Chris Moulin of the University of Leeds, U.K.

Yet when Moulin offered to help him, he adds, it was futile at first. The man “said there was no point visiting the clinic because he’d already been there.”

Déjà vu, which is French for “already seen,” is usually so fleeting that psychologists have until recently thought it impossible to study, Moulin said.

But for some people, the feeling of having been there before is persistent. Moulin and other researchers at the university are working with such people on what they say is the world’s first study of “chronic déjà vu.”

The man who refused treatment not only genuinely believed he had met Moulin before, he gave details about the times and places of the “remembered” meetings, Moulin said. The man believed he could hear the same bird singing the same song in the same tree every time he went out.
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Chronic déjà vu sufferers are not only overwhelmed by a sense of familiarity for new experiences, they can provide plausible and elaborate justifications to back up their feeling, Moulin said.

“When this particular patient’s wife asked what was going to happen next on a TV program he’d claimed to have already seen,” Moulin explained, the man said: “how should I know? I have a memory problem!”

But with the new study, those who suffer chronic déjà vu can help contribute to research into the problem, Moulin said. “So far we’ve completed the natural history side of this condition—we’ve found ways of testing for it and the right clinical questions to ask. The next step is obviously to find ways to reduce the problem.”

Ph.D. student Akira O’Connor is working with Moulin to find ways of creating the phenomenon in the laboratory. He has learned to actually create a sense of déjà vu in volunteers, using hypnosis.

O’Connor asks students to remember words, then hypnotizes them to forget. Next, he shows them the same word again to induce a feeling that they’ve seen it before. The students are then asked to provide reports on how how déjà vu feels, in addition to data about what they can and cannot remember.

“By considering subjective experience—feelings—from a cognitive science perspective, we hope to better understand everyday sensations like déjà vu, and also to help understand cognitive impairment, for example in older adults,” said Moulin.

“People might suffer from chronic déjà vu, but be unwilling to discuss this with their doctor; any hint of ‘mental illness’ is, particularly to older people, a taboo subject. But as soon as we found this first patient, we discovered that if you ask the right questions, you find other people have experienced the same thing.”

Chronic déjà vu can be distressing to the point of causing depression, and some sufferers have been prescribed anti-psychotics, Moulin said.

His group believe it is not a delusion, but rather a memory dysfunction. “The challenge is to think about what this means. We can use it to examine the relationships between memory and consciousness.

“The exciting thing about these people is that they can ‘recall’ specific details about an event or meeting that never actually occurred. It suggests that the sensations associated with remembering are separate to the contents of memory, that there are two different systems in the brain at work.”

Moulin believes a circuit in an area of the brain under the temples, called the temporal lobe, fires up when we recall the past. This creates the experience of remembering, but also a ‘recollective experience’—the sense of the self in the past.

In a person with chronic déjà vu this circuit is either overactive or permanently switched on, creating memories where none exist, he argues. When new events are processed, they are accompanied by a strong feeling of remembering.

A new collaboration launching this month with the University of York, U.K., will provide objective evidence to the subjective reports supplied by Moulin’s group, he added.

“When examining someone’s subjective experience, it’s important to have an idea of whether their subjective account is comparable to other people’s,” he explained. The neuro-imaging facilities at the University of York “allow us to see if the same areas of brain are activated in different people when they report certain subjective states. Ultimately, we may even be able to pinpoint the neural areas important for conscious states such as remembering.”

Moulin is keen to develop a network of patients in Leeds and across the globe who experience chronic déjà vu. “We’re finding people all over the world with these problems. Chronic déjà vu sufferers need the reassurance that they’re not alone, and we need them to help us learn more about who has it, what causes it, and why.”