People who claim they were abducted by aliens show more intense emotional reactions to their memories than some Vietnam War veterans, according to a Harvard study released Sunday.

Most researchers hailed the findings as significant in the field of recovered and false memories.

But a spokesperson for one controversial Harvard professor said the study may demonstrate something more significant—that humans may actually experience contact with a “third realm.”

Professor John E. Mack, a psychiatry professor at Harvard Medical School and a popular writer and commentator on extraterrestrial activity, has disputed the notion that alien abduction claims are fabricated. His spokesperson cites the study as evidence.

Most experts, however, say the study’s findings, presented by Professor of Psychology Richard J. McNally at the annual meeting of the American Association for the Advancement of Science (AAAS), show that emotional trauma can stem from imagined experiences.

“The core findings of this study underscore the power of emotional belief. If you genuinely believe to have been traumatized—even by an alien abduction, which we think is clearly fanciful—you show the psycho-physiological profile of those who have been,” McNally said.

In his study, McNally read abduction accounts both to subjects claiming to have been taken by aliens and to neutral controls, and found significant physiological differences in the reactions of the two groups.

The average increase in heart-rate of those who claimed abduction was 7.8 beats-per-minute, compared with no significant response from subjects in the control group. When Vietnam veterans suffering from post-traumatic stress disorder were subjected to the same procedure, the average increase in heart-rate is 3.2 beats-per-minute, McNally said.

William J. Bueché, communications director for Mack’s Center for Psychology and Social Change, said the physiological reactions may stem from contact with a spiritual reality that exists apart from the material and the non-material.

Bueché said McNally’s study is “a significant landmark in alien encounter research.”

He criticized McNally, however, for what he called his “leap of faith.”

“McNally assumes that the alien encounters are just beliefs…but that’s not clear-cut,” Bueché said.

McNally said he and Mack agree that the subjects had intense emotional experiences, and were not mentally ill; but he added he was “very skeptical” of the abduction narratives themselves.

This disagreement over the reality of the abductions is not new. In 1995, then-Dean of the Medical School Daniel C. Tosteson ’44 took the rare step of publicly warning Mack about the manner in which his research on alien abduction was affecting the academic standards of the Medical School.

Mack was forced to withdraw Harvard affiliation from his center, and asked by the Medical School to work with other researchers who were not immediately sympathetic to his work.

Some scientists said Mack’s research methods cast doubt on his interpretation of McNally’s study.

Arnold S. Relman, former editor of the New England Journal of Medicine and chair of an ad-hoc committee at the Medical School which investigated Mack’s research, said Mack has “only gone through the motions” of producing more objective research.

But Bueché said the accusations against Mack were “trivial” and that since 1994, Mack had brought together researchers in multiple disciplines, including McNally, to do research on alien abduction.

Relman, however, said he has been “disappointed” with what he called Mack’s lack of objectivity.

“If I were dean, I might have said to him, ‘John, for God’s sake, take a look at what you’re doing, you’re making a fool of yourself, and if you believe that you’re onto something of fantastic import... get some help from your colleagues,’” Relman said.