Beware a Rash of Exorcisms

If you think you know your own mind, think again.

Demonstrating the plasticity of memory, psychologists at the University of Washington in Seattle convinced students they witnessed demonic possession as children.

In a series of recent experiments, psychologists simply showed subjects newspaper articles about possession and then suggested symptoms of depression or anxiety were caused by witnessing a demonic possession during childhood.

Subjects who initially thought demonic possession was highly implausible became convinced they had witnessed it themselves when they were very young.

"It's relatively easy to make people believe they had an experience when they were children that they didn't have," said University of Washington psychologist Elizabeth Loftus, an expert in memory research.

"Even people coming into the study saying this is very implausible could be led to believe they had the experience themselves when they were very young."

Loftus predicted the current run of two movies dealing realistically with demonic possession -- the re-release of The Exorcist and Showtime's Possessed -- will have a similar effect and lead to a rash of exorcisms.

She said a "mini-epidemic" of exorcisms were reported after the initial release of The Exorcist in 1973.

"We saw thousands of people out there thinking they were possessed and asking for exorcism," she said. "I see no reason it wouldn't happen again."

In a series of experiments, 200 students from Italy were asked to rate their feelings about the plausibility of demonic possession and whether it had occurred to them as children.

Initially, all the subjects said possession was highly implausible and they had not witnessed one as a child.

To disguise the nature of the study, questions about possession were buried in a "life events inventory" that included dozens of questions about ordinary childhood experiences like accidents or getting lost at the mall.

Subjects then were presented with articles, stories or testimonials about possession that made it seem a plausible, not uncommon occurrence.

A week later, they filled out a "fear profile" concerning feelings of anxiety or depression as an adult. Again, the questionnaire contained a lot of red herrings.

After completing the fear profile, some of the subjects were given "false feedback" and were told their fears were caused by witnessing demonic possession as a child.

The researchers found that about 18 percent -- or one-fifth of these subjects -- later changed their minds about the plausibility of demonic possession and were convinced they had witnessed it as children.

"It's a minority," Loftus said, "but a very significant minority."

Three-quarters of the rest of the subjects also changed their opinions, but not quite as radically, Loftus said.

As a control, another group of subjects was told their fears were caused by a choking incident in early childhood. There was no change in the control group's attitudes about possession.

The research was led by Giuliana Mazzoni, a psychology professor at Seton Hall University, and included Irving Kirsch of the University of Connecticut.

It will be published next year in The Journal of Experimental Psychology: Applied.

Loftus said the experiments are consistent with a large body of research into the creation of false memories.