No drugs, no delirium, no blows to the head, yet you’re hallucinating. What, exactly, is going on? It could be your mind and/or your body dealing with some recent extreme stress, or it’s possible you just lost a family member. These, among other situations, are enough to trigger unwanted hallucinations, according to a recent study conducted by the World Health Organization (WHO).
After combing through completed surveys by over 31,000 people in 19 countries, the WHO study revealed that 1 in 20 people will experience at least one hallucination (not caused by drugs, alcohol, or dreams) in their lives. Participants were asked if they’d ever heard voices, seen something that didn’t exist, or suffered a delusion (i.e. – that they were being followed, or that God was speaking to them exclusively). The study excluded those who already suffered from a mental illness — like schizophrenia and manic depression — since those can cause hallucinogenic episodes; as a result, researchers concluded that hallucinations can occur even in the absence of mental illness.
“We used to think that only people with psychosis heard voices or had delusions, but now we know that otherwise healthy, high-functioning people also report these experiences,” said study co-author Dr. John McGrath, professor at the Queensland Brain Institute in Australia. “Of those who have these experiences, a third only have them once and another third only have two-to-five episodes across their life. These people seem to function reasonably well.
“So it’s incredibly interesting that not only is hearing voices more common than previously thought, but it’s not always linked to serious mental illness.”
Overall, nearly 6 per cent of people surveyed said they had experienced at least one hallucination or delusion in their lifetime. Hallucinations were much more common than delusions; about 5 per cent said they had experienced a hallucination, compared with only about 1 per cent who said they had experienced a delusion.
According to the National Institutes of Health, hallucinations can be normal in some cases: An oft-cited example is after a loved one dies — some people hear the person’s voice or think that they see the deceased, which can be part of the grieving process.
The study found that auditory hallucinations are more common in women than men, and they are also more common in people from wealthier countries.
Professor McGrath said the findings could help generate new research into the causes of these isolated symptoms.
“We’re interested in learning why some people recover, while others may progress to more serious disorders such as schizophrenia,” he said. “We need to understand why it’s temporary for some people and permanent for others. We can use these findings to start identifying whether the mechanisms causing these hallucinations are the same or different in both situations.”
Dr. Alan Manevitz, a clinical psychiatrist at Lenox Hill Hospital in New York City, said to Mashable that a number of psychiatric and medical conditions are linked with having hallucinations or delusions. These include personality disorders, post-traumatic stress disorder, obsessive-compulsive disorder, brain tumors, thyroid disorders, epilepsy, and certain infectious diseases and medications. Women can also experience postpartum psychosis (or psychotic symptoms after childbirth) that can include hallucinations, Manevitz said.
“We need to rethink the link between hearing voices and mental health — it’s more subtle than previously thought,” reiterated McGrath.
“While people may experience a false perception such as mistakenly hearing their name called out in public, hallucinations and delusions are quite detailed. For example, hearing voices that no one else can hear or a belief that somebody else has taken over your mind. People should be reassured that there isn’t anything necessarily wrong with them if it happens once or twice, but if people are having regular experiences, we recommend that they seek help.”