In some severe cases, believing you are possessed by a demon is an actual symptom of mental illness, said Justin Trottier with the Centre for Inquiry.
"There isn't a lot evidence to suggest that these claims for demonic possession are anything more than an association with known medical and psychiatric illnesses," Trottier said.
"We can't have unlicensed and unregulated individuals performing what essentially amounts to medical or psychiatric treatment."
Last week, there were reports that Saskatoon's Roman Catholic Diocese was searching for an exorcist after a priest was called to a home by a woman who said her uncle showed signs of being possessed by the devil.
Blessings were offered until his behaviour returned to normal, but church officials said no formal exorcism took place.
"In Jesus's ministry, there were exorcisms and so it's not something we can lightly dismiss," Bishop Don Bolan with the Saskatoon Roman Catholic Diocese said Tuesday.
"But the headline that the bishop of Saskatoon is looking for an exorcist is a vast oversimplification."
The church recognizes the importance of psychology and medicine to assist those struggling with mental illness, said Bolan, adding that prayer and spiritual support are part of the healing process.
"We are seeking as a diocese to determine how to pastorally respond to people in all kinds of situations of mental distress," he said, but looking for a priest trained in performing exorcisms isn't a priority.
"I've been a priest for nearly 21 years and I have never been a part of an exorcism, never heard a direct report of an exorcism," Bolan said.
It's important to not sidestep psychiatry and go straight into a spiritual practice, said David Nelson, executive director of the Saskatchewan branch of the Canadian Mental Health Association.
"There are mental illnesses that I would jump to — and I think professionals and most of our culture would jump to first — as opposed to a demonic possession," he said.
He said, however, there are rare circumstances where an exorcism might be helpful as an additional intervention, depending on the type of mental illness or psychiatric problem.
"In the context of a person's religion or their culture, it might be demonstrated that some sort of intervention, like an exorcism may be some help with that."
A recent survey the CMHA conducted about Canadians understanding of what mental illnesses are and what they are not revealed there is not enough being done to educate the public about various illnesses and what causes them, Nelson said.
"We found that there's still a tremendous amount of what you might just call plain old fashioned ignorance about the cause and the mythologies and the level of problem that mental illnesses are."
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