Imagine being emotionally unable to leave your home.

People who suffer from agoraphobia, one of the most severe and chronic anxiety disorders, experience anxiety and panic attacks while performing daily activities outside of their comfort zone.

But agoraphobia can be effectively treated by a new form of therapy developed by Larry Michelson, Penn State professor of psychology, and his former colleagues at the University of Pittsburgh.

The disease, once thought to be resistent to therapy, was not widely known until a decade ago, Michelson said.

Agoraphobics feel they must live within a specified area seen as safe. In extreme, untreated cases, agoraphobics become virtual prisoners in their own homes.

"It was so bad that it was like someone was putting a gun to my head just to leave the house," wrote Pat Woolsey of Paterson, N.J., to a California self-help institute.

Michelson explained that agoraphobia is nothing more than an intensified version of an animal's instinctive "fight or flight" reflex, which kept our ancestors alive by helping them respond to dangerous situations.

But this state of arousal -- often accompanied by physiological symptoms such as rapid heart rate, dizziness and difficulty breathing -- can turn to panic in which sufferers believe they are going insane or dying.

"Often, someone suffering from an attack will go to the emergency room because some of the symptoms resemble a heart attack. In some the panic goes away when they're told they're healthy. In others, the attacks may come back much worse," Michelson explained.

Michelson said this heightened stage of phobic anxiety is often preceded by an accumulation of stressful life events such as a job change, marriage or death in the family. These emotional jolts may occur from six months to a year before the onset of the anxiety attacks.

The new method of treatment involves cognitive therapy, or altering harmful beliefs that reinforce the disorder, combined with actual exposure to fearful situations.

At first, these "outings" are brief and the patient is accompanied by a therapist, Michelson said. Gradually, patients are exposed to more fearful scenarios for longer periods of time and with increased independence.

"The patients must learn there is nothing pathological about their panic attacks. It's a natural thing," Michelson said. "They must learn their panic is completely controllable."

Michelson explained most sufferers fall are between the ages of 18 and 35, but noted the fully developed condition of agoraphobia is not seen as often in students.

"Going out of the house comes with the territory of being a college student," he said. "People with agoraphobia wouldn't sign up for school in the first place."

In a recent University of Pittsburgh study funded by the National Institute of Mental Health, Michelson and fellow researchers discovered that cognitive therapy, combined with exposure, generated an 86 percent success rate. This compares to the 65 to 70 percent rates associated with other treatment methods such as relaxation training.

Michelson is performing a similar follow-up study at Penn State with students and faculty who may have been experiencing panic attacks with or without phobic avoidance.

He is looking for about 60 clients and urges sufferers with an interest in the three-year study to contact the University's Stress and Anxiety Disorders Institute, founded last September.

The seven professors at the Institute treat patients of all ages in the Centre County region.