For the past twenty years, 57-year-old clinical psychologist Michael Telch has seen around ten patients every week, some of them so afflicted by anxiety that they’ve had trouble simply getting to his office. One woman, who’d often spend eighteen hours a day chanting to herself in the shower, had to be physically retrieved for her first session. Another had been scared to leave her bedroom for fifteen years. But while some clinicians might be frustrated by such challenges, Telch doesn’t express the faintest irritation. These are his people.

Telch is the founder and director of the Laboratory for the Study of Anxiety Disorders at the University of Texas at Austin, also known as the Telch Lab. He bears a slight resemblance to Mel Gibson, if Gibson’s face were frozen in an expression of extreme concern. He speaks calmly, a trait one might expect in an anxiety therapist, and moves his hands slowly while he talks, stirring tea if he’s at his office or, if he’s at home, petting one of his springer spaniels, who like to curl up in his lap and snore like a buzz saw.

Much of Telch’s research involves exposure therapy, a potent anxiety-reducing technique that has become prevalent over the past few decades. When I visited his office in January, he explained how it worked. Say a person is afraid of frogs. “In the old days, a psychoanalyst might have assumed the phobia was symbolic of a deeper disturbance,” he said. “The therapist would probe the person’s childhood history, investigate how they were toilet trained, and year after year, hundreds of thousands of dollars later, the phobia still was not gone. Now we can treat patients in a few sessions.”

“Just put a frog on them?” I asked.

“Well, basically, yes,” he said. “But it usually starts with looking at pictures of frogs. I’ve had some serious snake phobics where we had to start by drawing a line on a piece of paper. I’d say, ‘Imagine that’s a snake,’ and the patient would scream, ‘Aahh!’”

Variations of this technique—in conjunction with other methods—are used in most of Telch’s cases. Afraid of flying? He’ll take you on a plane ride. Afraid of heights? Look over the balcony. Claustrophobic? Get in this box. Telch has treated a bewildering variety of ailments—arachnophobia, cynophobia (fear of dogs), obsessive-compulsive disorder, even the fear of fear itself. But until five years ago he hadn’t spent much time researching one devastating condition: post-traumatic stress disorder, the long-term debility caused by exposure to a traumatic event. PTSD victims often suffer from flashbacks, insomnia, and intense anger, among other symptoms.

Telch’s professional focus widened in the spring of 2005, after he was contacted by Brian Baldwin, who was the project manager of UT Austin’s new neuroimaging lab, the Imaging Research Center (IRC). A former Army colonel, Baldwin had once supervised two detachments of psychologists and specialists who helped soldiers cope with combat stress. After the Iraq and Afghanistan wars began, he saw an alarming rise in the number of PTSD victims. Reportedly, between 11 to 20 percent of veterans showed symptoms of PTSD, compared with 2 to 10 percent of veterans of the first Gulf war. Baldwin was surprised. The Army, he believes, has done a great deal to fight PTSD. It has provided psychological care during combat operations and tried to get to the afflicted early. It has also tried to cement the bond between a soldier and his unit, which has been shown to improve the welfare of the soldier when he gets back home. “I thought, ‘Gosh, you know, we’ve done a lot to try to take care of this,’” he said.

But despite such efforts, the nature of combat in the Middle East, in which insurgents are around every corner, is taking a psychological toll. The constant vigilance that serves a soldier well overseas can become an issue when he returns home. The most typical, noticeable effects—relationship problems, for example, or a loss of productivity—are difficult enough. Even more grave is the prevalence of substance abuse, homelessness, and suicide among PTSD victims. According to a recent report, 160 active-duty soldiers killed themselves in 2009, more than in any year since the Army began keeping track of suicides three decades ago (though no conclusive link has been made between these suicides and PTSD).

Baldwin did some research and found that for all that scientists understand about how people develop PTSD, no one has ever definitively determined what predisposes a person to the disorder. Different people, after all, have different responses to traumatic events. But no one is sure why. Is it brain function? A behavioral disposition? Baldwin had an idea: Why not take pictures of soldiers’ brains before they leave for combat, take more pictures when they return, compare the results, and keep track of who does and doesn’t develop PTSD? Baldwin knew he could get some soldiers from nearby Fort Hood on board; all he needed was a scientist to lead the project.

Telch recognized the unique opportunity he was being offered. “For PTSD, too much focus has been on the treatment rather than its causes,” he said. Sufferers can see a psychologist or take drugs such as Zoloft and Paxil, which have been shown to help. But not all the soldiers who need assistance will get it. According to a 2008 RAND Corporation study, only slightly more than half of the soldiers returning from combat in Iraq and Afghanistan with symptoms of PTSD and depression sought treatment, and only half of those received treatment that was considered “minimally adequate.”

Telch wasn’t the first researcher to try to determine what predisposes people to PTSD. But the vast majority of risk assessments had taken place after the patients had been diagnosed, and those reports relied on questionnaires that focused on broad demographics—rank, race, gender. These biographical details offered helpful clues but little more. Telch suggested a far more comprehensive attack that would include genetic and cognitive elements, pre- and post-deployment tests, and online stress surveys completed by the participants while they were in Iraq.

The upside of such a study is obvious: If the military could predict which soldiers were most vulnerable to PTSD, it could monitor them closely, during and after combat. But Telch hopes that in a future study he’ll be able to take the research one step further. Might it be possible, he wondered, to “inoculate” soldiers against PTSD before they head off to war?

There’s a precedent for inoculating people against future anxiety disorders. Take, for example, the research that has been done with carbon dioxide. Numerous studies have shown that when people inhale a gas mixture that is 35 percent carbon dioxide—which induces breathlessness and light-headedness—some remain calm while others panic. Telch’s preliminary research suggests that those who panic are more susceptible to anxiety problems in general, and he believes this predisposition can be remedied. With repeated exposure to the carbon dioxide mixture, patients can train themselves to modify their response—a behavioral change that, Telch believes, will apply to other anxiety-causing situations. People, it seems, can be taught to keep their cool.

“The Army requires demanding drills, such as exposure to gunshot noise,” Telch said of the preparation soldiers undergo before deploying. Perhaps, he suggested, soldiers with a predisposition to PTSD could undergo a specialized stress-training regimen, such as CO2 therapy. “This would be just another set of drills to knock out their anxiety sensitivity,” he said. It would be a completely new strategy for attacking PTSD—the difference between improving cardiac surgery techniques and figuring out ahead of time who might benefit from cutting back on bacon cheeseburgers.

In the fall of 2007, 184 Fort Hood soldiers who had volunteered for Telch’s study began visiting the IRC, a plain one-story building in North Austin. They had never been deployed, but in a few weeks nearly all of them would be sent overseas. Most of them would prove to be resilient in the face of their ordeals. A few wouldn’t be so lucky.

Since researchers have established an association between prior mental illness and PTSD, the first tests assessed the participants’ mental health via online surveys and clinical interviews. “Before the soldiers left and then when they returned, they were administered a structured, gold-standard diagnostic interview,” Telch said. Depression, anger, dissociation, social support, and alcohol and drug use were a few of the indicators researchers were measuring.

Next, each soldier lay down inside a magnetic resonance imaging machine that recorded his brain structure and activity. The primary areas of interest were the prefrontal cortex—the area that moderates social behavior—and the amygdala and the hippocampus, segments that, along with the prefrontal cortex, work together as our internal warning system. Some PTSD patients display abnormalities in all three areas: underactive prefrontal cortices, hyperactive amygdalae, and shrunken hippocampi. But researchers weren’t sure if abnormalities were present before the onset of PTSD or materialized afterward. Were they a cause or a consequence?

Telch also looked into the soldiers’ genetic vulnerabilities. Researchers had soldiers spit into small cups and then examined their DNA for evidence of the serotonin transporter gene, which has been shown to predict risk for depression and anxiety if a particular variant is present. Then the soldiers participated in eye-tracking experiments, which recorded what they looked at on a computer screen. Last winter, at the IRC’s eye-tracking laboratory, Christopher Beevers, the project’s mood disorder specialist, explained to me how his state-of-the-art device worked. “The basic idea is, you present different images to individuals and directly measure their line of gaze,” he said. The equipment, which looks like a typical flat-screen computer monitor, shines an infrared light that bounces off the eye and correlates the reflection with anchor points on the screen. Using his eye-tracking software, Beevers can ascertain precisely what a viewer is looking at on the screen and for how long. He can even generate a map showing the order in which the viewer looks at each spot. To demonstrate, he tapped on his keyboard and produced a screen separated into four quadrants. Each portion displayed a black and white photograph of a man’s face: One exhibited fear, one happiness, one sadness, and one no emotion at all. In theory, folks who are prone to depression are likely to spend more time looking at sad faces; people who are prone to PTSD are likely to avoid the frightened faces.

The final station was Telch’s carbon dioxide challenge. After the participants were fitted with a heart-rate device, they took one deep breath of the gas mixture. Telch instructed them to hold it in their lungs for five seconds. In PowerPoint presentations, Telch likes to play a video of previous tests with college students showing the variety of responses to the gas. In the first segment, a student inhales deeply through a gas mask, holds his breath for a few seconds, and almost immediately goes into a panic attack. His eyes dart around the room and he looks completely freaked-out, grabbing the researcher’s arm and pitching forward. In the second segment, a student takes a breath and holds it as if it were a bong hit, giggling as he lets it out; he pumps his fist, then flops back into the chair with a big smile on his face. “Some people get really scared of the CO2 ,” Telch said. “Some people actually enjoy it.” Past experiments have demonstrated that those who panic are susceptible to anxiety problems. But only after deployment would Telch be able to determine what this might mean for soldiers in combat.

Most of the soldiers who participated in the study fought in Iraq for fifteen months; thirty to ninety days after their homecoming, 162 of them returned to the IRC for a post-deployment round of tests. The results aren’t definitive enough that the Army is about to subject all incoming soldiers to carbon dioxide tests; for one thing, it’s too early to know which soldiers will develop PTSD, a condition that often emerges months or years after the precipitating event. (At most, Telch and his team have observed symptoms of what might turn into full-blown PTSD.) But the results trickling in show promise. Sitting at his computer two and a half years after he began the study, Telch pointed to a chart that confirmed that, as past research had shown, those who had a history of mental disorders were much more vulnerable to stress, depression, and what appeared to be early PTSD symptoms. Other findings broke new ground: In the short time during and after deployment, those who had avoided fearful faces in the eye-tracking tests and who had displayed high reactivity in the carbon dioxide challenge exhibited more stress and possible PTSD symptoms. Neuroimaging and genetic factors were still under evaluation, but Deborah Stote, a neuroscientist working on the project, said, “I would bet my bankroll that the people with early PTSD symptoms will show decreases in the size of the hippocampus.” If that is the case, pre-trauma hippocampal size can be ruled out as a predictor of PTSD.

There is still plenty of work to do. Telch is seeking funding to extend the current study, so he can track what happens as some of his test subjects develop PTSD. He also wants to launch a larger study of more than three hundred soldiers. And, at some point, he will want to test out various methods of inoculation. Still, Baldwin believes this first report is a major step. “We didn’t start out thinking we would find a silver bullet,” he said. “But world-changing discoveries occur because people believe that a silver bullet is possible.”

Of course, no treatment will ever offer a cure-all for veterans. Combat trauma produces anxiety and painful memories even in the hardiest soldier. But the men and women who suffer from post-traumatic stress disorder carry a far greater burden: decades of debilitating mental anguish that can destroy their lives and the lives of those around them. If counterinsurgency is the future of military engagement, and the wars our soldiers will fight in the years to come are anything like the wars they are fighting now, a cure can’t come soon enough.