The lateralization of atypical facial pain.

Various theories have been proposed to explain the reported predominance of left-sided symptoms in patients with conversion disorders, psychogenic symptoms, and chronic pain. In a population of 110 patients with atypical facial pain (AFP), there were no significant differences in the side of pain or lateralization of pain between psychiatric and non-psychiatric patients. A non-significant trend to left-sided pain in psychiatric patients was found if only those patients with lateralized pain were examined. The significance of these results to etiological theories of chronic pain lateralization is discussed.