Left out of my recent story on déjà vecu were some of the more interesting studies trying to create déjà vu-like sensations in a laboratory, in order to better understand what causes the everyday version of the phenomenon. Akira O’Connor, a grad student of Chris Moulin (the déjà vecu researcher in the article) has had success using hypnosis to create a similar strange sensation of familiarity. Alan Brown at SMU and Elizabeth Marsh at Duke University also have a clever experiment, testing the theory that actual memories can sometimes trigger déjà vu. Here’s my outtake section on the research:

“There is almost a bit of a loneliness about déjà vu to start with,” Akira O’Connor, Moulin’s graduate student, told me one morning at the University. “When you get it, you wonder if you are the only person in the world to have had that feeling.” O’Connor, whose research involves trying to induce déjà vu through hypnosis, was bothered by frequent déjà vus as a teenager. Then he read Joseph Heller’s Catch 22, with its lengthy discussions of what Heller describes as “a weird, occult sensation of having experienced the identical situation before in some prior time or existence.” Reading Catch 22, O’Connor says, “let me know that I wasn’t going mad.”

In a basement soundproof room at the University of Leeds, I watched through a window as O’Connor conducted his latest experiment. A curly-haired female student volunteer sat at a computer, watching as a series of words flashed by on the screen. O’Connor then sat across from her and asked her to close her eyes. “I want you to focus on the sound of my voice,” he said, reading from a printed script in a soothing baritone. “Now start to relax…you are feeling deeply relaxed.” This went on for about 15 minutes, the point at which the student should have been fully hypnotized. (Not everyone is susceptible to hypnosis, and O’Connor was unable to put under Moulin or myself.) He told her that when she awoke, she would find words with a green or red box around them familiar. He then brought her slowly out of hypnosis and returned her to the computer, where a new series of words flashed by, some from the original list and some new. This time, the words were surrounded by green, red, or blue rectangles.

The goal, O’Connor had told me, was to use the green and red boxes to try to produce a vague feeling of familiarity for words that aren’t on the original list. With luck, that familiarity would feel a lot like déjà vu. On the screen, the student clicked on a scale to indicate how familiar each word seemed, and then filled out a written survey.

Afterward, O’Connor asked the student whether she experienced any déjà vu during the experiment. “Well, when I saw the color blue,” she said. O’Connor seemed perplexed — it was the opposite of the intended effect. “That’s interesting,” he said. “I’ve never heard that before.”

The episode revealed the sometimes unpredictable nature of hypnosis-based research. But O’Connor was encouraged by his results so far. The green and red rectangles did seem to be inducing inappropriate familiarity. More significantly, over 50 percent of the students, when asked if they’d “experienced any strange sensations” during the experiment, had mentioned déjà vu.

Alan Brown at SMU, together with Elizabeth Marsh at Duke University, recently conducted a series of similar experiments, attempting to recreate déjà vu-like feelings without hypnosis. Brown and Marsh showed students at SMU and Duke sets of pictures which included shots from both campuses. Two weeks later, the same students were shown another series of pictures and asked to assess whether they’d ever been to the photographed locations. The researchers hypothesized that at least some déjà vu’s are caused by a person having “experienced the present situation or setting (or some part of it) on a prior occasion, either in person, vicariously through media (magazine, movie) or in a detailed verbal description.”

The results, currently submitted for publication, showed that exposing the students to a location via a photo made them significantly more likely to say they’d been there, even if they hadn’t. More than half of the participants replied yes to a question about whether they had “experienced déjà vu or something approaching it during the experiment.”

Such studies are the first step toward understanding the multiplicity of déjà vu’s causes. “It’s kind of like taking the layers apart, peeling the onion down,” Brown says, “and making a prediction about, ‘is this a mechanism for déjà vu?’ If it is, then we should find it happening in the lab. It won’t be quite as exciting as that rush, that emotional cognitive experience that you have with a full blown déjà vu.”

Posted at 12:24 pm | Filed under Deja vu, New York Times, Recent stories |

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