MINNEAPOLIS – There’s never been a simple test to diagnose post-traumatic stress, but a group of Minnesota scientists say they’ve found a high-tech way to identify people who have the disorder – by studying their brain signals.
The discovery could have huge implications for the way PTSD is diagnosed and treated in the future, says Dr. Apostolos Georgopoulos, who led the research as director of the Brain Sciences Center at the Minneapolis VA Medical Center.
PTSD is thought to afflict tens of thousands of combat veterans, but it can be hard to diagnose. It’s a collection of psychological symptoms that can, in some cases, be caused by other conditions, such as head injuries or depression. That’s one reason that exact numbers are hard to pin down; the VA estimates that anywhere from 11 to 20 percent of returning veterans from Afghanistan and Iraq have PTSD.
But in a study released Wednesday, Dr. Georgopoulos and his research team found what they call the first “biological marker” for PTSD: a distinctive pattern of brain signals that can be detected with a $2 million device called MEG (magnetoencephalography).
“The brain patterns are very different,” said Georgopoulos, who has been studying brains for 30 years.
In men and women with PTSD, he said, the machine found a cluster of abnormal brain signals in an area of the brain involved in memory. Exactly why is still a mystery, but he speculates that it may interfere with the ability to suppress bad memories, one of the hallmarks of post-traumatic stress.
Georgopoulos, who is also a neurology professor at the University of Minnesota, is one of a growing band of scientists using brain imaging, such as MEG and PET scans, to study psychiatric disorders.
“That’s a big area in psychiatry,” said Dr. Monte Buchsbaum, a leading brain researcher and psychiatrist at the University of California at San Diego. “Mental illness is a devastating brain disease, and we now have better technology to look at the brain in action.”
Three years ago, Georgopoulos led a small study of patients with Alzheimer’s, schizophrenia and several other brain disorders, and found that each group had a distinctive pattern of brain signals when examined with the MEG device, which measures moment to moment changes in the brain’s electrical activity.
For the latest study, he and his team recruited several hundred veterans from Minnesota and Wisconsin, spanning every war since World War II. Among them were 74 men and women who had been diagnosed with PTSD.
One was Gary K. Lore of Minnetonka, Minn.
Lore, 62, served two tours of duty in Vietnam in the 1960s. The experience left him with “horrendous nightmares,” flashbacks, sleeplessness and other classic symptoms of post-traumatic stress, he said. Yet it took more than two decades to get a diagnosis.
“I just thought I was another crazy Vietnam vet,” he said. It wasn’t until the Gulf War in 1991, when he watched the horrific images on TV, that Lore realized he needed help. Since then, he’s been treated successfully with therapy and medications, he said, and gets checkups at the Minneapolis VA.
Lore went to the VA hospital’s Brain Sciences Center, and allowed researchers to scan his brain. He fixed his eyes on a spot for 60 seconds at a time while the MEG device, which looks like a science-fiction helmet, measured the tiny magnetic fields emitted by the electrical signals in his brain. The result was a sort of footprint of the brain’s activity at any given moment.
By studying the images of all the volunteers, the scientists were able identify the patients with PTSD 97 percent of the time, said Georgopoulos. Even among patients who had recovered, the pattern was still visible, though less intense.
Georgopoulos said the technique could also help treatment, by allowing doctors to monitor how well the brain responds to different therapies.
Andrea Northwood, a Minneapolis psychologist who treats patients with PTSD at the Center for Victims of Torture, said she would welcome a device that could make her job easier. “With these kinds of complex behavioral conditions, we need as many tools as possible,” she said.
Georgopoulos notes that the device itself is harmless, emits no radiation, and can be safely used even “in newborns.”
Yet it may be some time before the brain scans are widely available. The MEG devices are costly and rare, and mainly used in research. But that could change, Georgopoulos said, if the device proves to be as useful as it appears.
For Lore, the veteran, it was “a relief” to learn the results of his brain scan. “It wasn’t just because I couldn’t think straight or whatever; there were real changes in the brain,” he said.
Georgopoulos says his discovery does not mean the damage from PTSD is permanent. “I’m optimistic that this is a reversible condition,” he said.
The study appears in the Jan. 20 online issue of the Journal of Neural Engineering.