Scientists are taking a second look at so-called magic mushrooms, a staple of 1960s hippie culture, to see if they do open a pathway to the divine.

Or, failing that, to help with addictions or terminally ill patients fighting depression and anxiety.

The active ingredient in the mushrooms is the psilocybin, a hallucinogen.

"This is a class of compounds, the classical hallucinogens, for which research has been in the deep freeze for about 40 years," said Dr. Roland Griffiths of Johns Hopkins University in the United States.

His new study was published Tuesday by the journal Psychopharmacology.

Use of magic mushrooms by native Americans in religious rituals predates their use by hippies.

In the Johns Hopkins study, two-thirds of the 36 volunteers, given capsules of psilocybin extracted from the mushrooms, claimed they had what they described as a religious experience.

By that, they meant a sense of pure awareness, transcending time and space and feeling positive moods like joy, peace and love.

They claimed it changed their lives for the better. Not only that, one-third said the experience was the most significant of their lives, likening it to a child's birth or a parent's death.

Two months later, almost 80 per cent of the volunteers reported feeling ongoing positive effects.

On the God stuff, however, Griffiths said not so fast.

"Just because we can describe the neurophysiology of this kind of experience says nothing about the existence or non-existence of higher power or God," he said.

Religious leaders were also skeptical. "... I'm very, very suspicious about whether these experiences are genuinely spiritual," said Fr. Terry Kersch of St. Basil's Parish in Toronto.

At least one-third of the volunteers experienced a bad trip, including feelings of intense fear and paranoia, even though they took it under controlled conditions.

Psilocybin acts as a message-carrier between brain cells in the same way as serotonin, a major mood-monitoring chemical in the brain.

"There might be some application with these drugs for individuals who have anxiety or depression," Griffiths said.

Some doctors also think the research might have value some day in treating addictions.

While hallucinogens haven't caught on with today's youth, one critic hopes it stays that way.

"It's a very vulnerable age and you don't want them to be experimenting with it," said Wende Wood of the Centre for Addictions and Mental Health in Toronto.

Griffiths also strongly warned people not to try the drug at home.

With a report from CTV's Peter Murphy and files from The Associated Press