It's easy to conjure false memories, UA researchers say

In a study of Tucson teens and college-age students, two UA psychologists have found that people may mistake false memories for real occurrences.

Charles Brainerd, a University of Arizona educational psychology professor, and Valerie Reyna, an associate surgery professor, conducted memory experiments that call into question the method of police interrogations and psychotherapy.

In the study, doctors read 140 patients lists of words, some centered on themes and others at random, and recorded the patients' responses.

"I was shocked by how easy it was to create false memories," Reyna said.

Patients were read lists of words like: sick, patient, ill, hospital and cure, Brainerd said. Then the patients heard two more lists of the same format, but about another topic.

He said 68 percent affirmed the word "hospital" was on the list, but 88 percent said "yes" to the word "doctor."

When patients were confronted with words that sounded like they would be on the lists, even if they were not, many responded positively, Brainerd said.

The phenomenon was likened to police interrogation because through questioning, people can be led to believe something happened when it didn't, he added.

"Witnesses are encouraged to dredge up anything from their memories," Reyna said. "The bottom line is to be very cautious when interviewing witnesses."

False memory also applies to psychotherapy because it revolves around patients' problems, and suggestive questioning may cause them to recall false accounts of events.

The topic gained national attention in the 1995 court case, Kelly Michaels vs. New Jersey. Michaels, a preschool teacher, was accused of multiple counts of child abuse by her students based on police interrogations and psychotherapy.

Michael's convictions were reversed because the evidence was tainted. The children's testimonies were inconsistent when they were questioned in court and outside the courtroom.

The inconsistency was caused by the manner in which questions were asked when witnesses were not in the courtroom, Brainerd said.

The children were interviewed in a "suggestive" - or non-straight forward - manner, he said. The appeal included a review of child-memory research, said Brainerd, who conducted some of the studies.

Reyna said police interrogators and psychotherapists should take advantage of the research.

"There are people attempting to put this into practice, but it's not widespread," she said. "There is the risk of the inadvertent retrieval of events that did not occur."

Another experiment the team conducted involved a list of three fruits, like apple, banana and pear. Reyna said patients would often answer "yes" to other fruits when asked.

The participants are usually highly confident about the false memory words, she said.

The husband and wife team will report its findings in the November issue of Psychological Science.

Irene Hsiao can be reached via e-mail at Irene.Hsiao@wildcat.arizona.edu.