Panic disorder is caused by an abnormality in the brain, not a weakness in character as is commonly believed.

People who have sudden heart-pounding panic attacks are missing a key component of a chemical messenger system that regulates emotion. This finding was recently announced by the National Institutes of Health and reported by the Associated Press. Dr. Conrad Swartz, professor and chief of psychiatric research at SIU School of Medicine in Springfield says people who have panic attacks experience chemical changes in the brain.

SOUND BITE: ". . . these changes indicate a deficiency of serotonin in the brain. I believe these changes are the result of the panic disorder. But there is no question that correcting the changes decreases the symptoms - decreases the amount of worry and fear that people with panic disorder experience."

About 2.4 million Americans have the disease, which can leave its victims in constant fear of attacks, extremely worried, and with thoughts of impending death. Panic attacks can resemble a heart attack or cause chest pains, sweating, trembling, shortness of breath, choking feelings or dizziness. Dr. Swartz says there are effective treatments including medications for panic disorder.

SOUND BITE: "One kind of treatment decreases worrying and dissatisfaction which I call psychological anxiety. A second kind of treatment decreases body tension and the fight-or-flight adrenaline reaction. It decreases what is called the sympathetic nervous system. And the third kind of therapy is psychotherapy, which in which you learn how to avoid stresses - how to not take stressful events personally."

Individuals who think they have signs of panic disorder or other anxiety disorders should see their primary care physician or a mental health counselor for evaluation and treatment.