February 4th, 2012
10:34 AM ET
When 12 students at a high school in New York suddenly developed strange symptoms like stuttering, uncontrollable twitching movements and verbal outbursts, the community was concerned. Was there something in the environment? Was it a virus of some sort spreading dangerously? Three students and one adult have since also exhibited the same symptoms. Doctors at DENT Neurologic Institute have now diagnosed some of the girls with "conversion disorder," leaving people even more confused.
What is conversion disorder?
A person with conversion disorder has neurological symptoms that aren't related to any known neurological condition, according to the American Psychiatric Association. The symptoms could appear as uncontrolled motions or verbal outbursts, like the students in New York, or as anything from weakness or paralysis to a loss of vision or hearing.
In diagnosing conversion disorder, doctors must first rule out other neurological diseases and determine that the symptoms are not being intentionally faked. Often the symptoms are inconsistent with typical signs of a neurological disease – either physical signs or those that might show up on a diagnostic test.
What causes conversion disorder?
Stress is the main underlying cause of conversion disorder, says Dr. Jay Salpekar, director of the Neurobehavioral Program at Children's National Medical Center in Washington. That stress can be physical or psychological, and the amount that would cause the disorder varies in every person.
"The bottom line is that this stress is somehow converted into a physical symptom," Salpekar says. "Everybody has their breaking point."
Stress can also aggravate another underlying medical condition that was previously undiagnosed – and may never be. "We have many tools available with modern medicine, but we don't know everything."
What's the difference between conversion disorder, mass psychogenic illness and mass hysteria?
The official name for this disorder is still being debated. The American Psychiatric Association's current Diagnostic and Statistical Manual – or DSM-IV – calls it "conversion disorder."
The new version, DSM-5, which is set to publish in May 2013, is proposing a change to call it functional neurological disorder. In the past, the disorder has been called mass psychogenic illness or, more simply, mass hysteria. All the names describe the same disorder.
It's important to note that conversion disorder is not a group diagnosis, but an individual one.
"It's very unusual to have conversion symptoms that are 'contagious,' " Salpekar says.
Psychiatrists often refer to cases like the one in New York as a conversion reaction – or a group's reaction to conversion disorder.
Has this happened before?
Conversion disorder on an individual basis is common, Salpekar says. Conversion reaction hasn't been well documented. Most of the people involved in group incidents don't seek mental health help and are never officially diagnosed with conversion disorder.
Conversion reaction can be cultural, as it was in Trinidad in 2010 when students at a secondary school started screaming and collapsing. The phenomenon was attributed to demonic possession, according to a local newspaper, which may have helped it spread.
In 2007, nine students and a teacher at William Byrd High School in Roanoke, Virginia, complained of "involuntary movements in the extremities," according to The Roanoke Times. Environmental tests done at the school came up clean. While the principal told CNN that six students were determined to be faking, the Virginia Department of Health did an investigation and concluded the students' symptoms were consistent with "mass psychogenic hysteria."
In 2004, 31 chorus members at Starpoint High School in Lockport, New York, fell ill within an hour. Tests on the students and the building couldn't determine a cause, and everyone recovered quickly, according to a local news report.
The list goes on: in 2007, 14 female high school students in Florida who developed sudden loud breathing problems; in 1982, 100 people in Los Angeles who thought they had food poisoning, but didn't; in 1977, factory workers in West Virginia who passed out by the dozens.
Is it always women?
Many of these examples involve a group of young female students. But Salpekar warns against taking that as a sign conversion disorder or reaction only happens to women. Females are just more likely to seek help or bring attention to their symptoms, he says.
Are we sure it's not just a hoax?
Some people obviously do fake symptoms – psychiatrists call them maligners. These people always have something to gain from doing so, whether it's money in a lawsuit or a long stint off from work. But few people intentionally make up symptoms that make their lives more difficult for no reason, Salpekar says.
"To say that they're faking, it's just inappropriate. People do not fake things that adversely affect their life in such a way. ... [Conversion disorder] is simply a reflection that something is wrong in the mind, brain and body."
Can it be treated?
Yes. First, doctors treat any underlying medical or psychological conditions. Anti-anxiety drugs can be prescribed to help with the stress, according to the Mayo Clinic. Counseling is used to calm symptoms and teach stress management techniques. Other treatments include physical therapy to help with uncontrollable movements, hypnosis and/or magnetic stimulation in the brain.
About this blog
Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love.