It has been shown in a recent study that there is no relation between using peyote and brain damage or psychological problems. This hallucinogenic cactus is often used by American Indians in religious ceremonies.

Also, in McLean Hospital, researchers from Harvard found that members of the Native American Church performed better on some psychological tests than other Navajos who did not regularly use peyote.

Since 1994, for 300,000 members of the Native American Church, it was legal the usage of peyote as a religious sacrament. Five years of study showed that the hallucinogenic substance is not a dangerous one even if used frequently.

John Halpern, a psychiatrist of McLean conducted the study. The study has been made on 60 persons who used peyote at least 100 times, comparing them to 79 persons who did not use peyote frequently and 36 persons who seldom used peyote but who have a history of alcohol abuse. The results showed the last ones were worst on the test. It is not proved that peyote has a pharmacological effect that improves human health.

Harrison Pope, the senior author of the study and director of the biological psychology laboratory at the hospital said: "It's hard to know how much of it is an actual sense of community they get (from the religion) and how much of it is the actual experience of using the medication itself,"

'Reassurance' for religious users

The researchers argue that their findings should offer "reassurance" to the 10,000 Native American Church members serving in the military who were barred from using peyote before new guidelines were adopted in 1997.

They wrote in their paper published in the Nov. 4 issue of Biological Psychiatry: "We find no evidence that a history of peyote use would compromise the psychological or cognitive abilities of these individuals,"

There must be a clear distinction between religious and illegal use of peyote. They assumed that other hallucinogens such LSD could be dangerous.

No 'flashbacks' observed

The mescaline, which is a substance contained in peyote, is described as more sensual and perceptual in comparison to LSD, and also less altering of thought and sense of self. The peyote does not seem to produce "flashbacks" in the same way as LSD.

This study was funded by National Institute on Drug Abuse, which is part of the U.S. Department of Health and Human Services. A NIDA spokeswoman would not comment on the study.

"The thing that excites me most about the paper is that the study was actually done", said Lester Grinspoon, a Harvard Medical School psychiatry professor who was not involved in the research. "The U.S. government - and NIDA, in particular - have been rather balky about allowing studies of psychedelic drugs of any kind before."