Positron emission tomography was used to study eight patients with panic
disorder who were vulnerable to lactate-induced panic, eight patients with
panic disorder who were not vulnerable to lactate-induced panic, and 25
normal control subjects. Patients who were vulnerable to lactate-induced
panic had several abnormalities in the resting, nonpanic state: an abnormal
hemispheric asymmetry of parahippocampal blood flow, blood volume, and
oxygen metabolism; abnormally high whole brain metabolism; and abnormal
susceptibility to episodic hyperventilation. A hypothetical model for the
neurobiology of panic disorder, involving the abnormal parahippocampal
region and its afferent and efferent connections, is proposed.Abstract Teaser