Washington, a city of many public places, would be a good town for the professor to look for volunteers from among sufferers of agoraphobia.

Dr. James C. Ballenger, professor of behavioral medicine and psychiatry at the University of Virginia in Charlottesville, is seeking 75 to 100 volunteers for a study of agoraphobics. That's people who are afraid of public places.

Dr. Ballenger said that he is most interested in people who have not sought treatment for their unusual malady, and who seek solace in the isolation of their homes.

When they go into public places, these people suffer such symptoms as heart palpitations, chest pain, dizziness, hyperventilation, a lump in the throat, weakness in the legs and an overwhelming fear of impending death.

In other words, they have an onset of the feelings most of us get when an unexpected letter arrives from the IRS.

Some agoraphobics, when shopping, will wait for checkout only if they're the last in line, Dr. Ballenger said. If someone gets behind them, they'll flee to another line.

Most agoraphobics think "they're just odd people and that they are weak . . . [and] keep it to themselves," Dr. Ballenger said.

Volunteers should contact Dr. Ballenger at the public place where he works, the anxiety and panic disorder clinic at the U-Va. Medical Center.