The notion that symptomatic patients with mitral valve prolapse are "neurotic" is far from defunct. But new research suggests that their "neurotic" symptoms—hyperadrenergic responses, hypervagal responses, or, in some patients, both—actually reflect an abnormality in central (midbrain) regulation of autonomic function. This abnormality may be structural and congenital in origin. Treatment is pharmacologic, not psychotropic, and is aimed at central modulation of the patients' abnormal sympathetic or parasympathetic activity. H. Cecil Coghlan, MD, professor of medicine, University of Alabama School of Medicine, Birmingham, has studied and treated about 600 of these patients, following up 70% of them for more than two years and 4% for five to six years. Coghlan puts each patient through a series of noninvasive diagnostic tests, taking care to minimize the "laboratory" ambience and to decrease patients' anxiety, with the goal of duplicating the everyday situations that precipitate their symptoms. Thus, he will ask the patient