The goal of this research is to identify and to describe systematically those psychotic patients who demonstrate abnormal hemispheric asymmetries of function. Hemispheric functioning will be measured by three left-hemisphere and three right-hemisphere clinical neuropsychological tests. The left-hemisphere tasks will be 1) analogies, 2) a test for naming, 3) identification of unseen forms felt by the right hand. The right hemisphere tasks will be 1) line orientation, 2) dot localization, and 3) identification of unseen forms felt by the left hand. The measures of left- and right-hemispheric functioning will be psychometrically matched so that specific differential deficits in hemispheric functioning can be measured independently of generalized performance deficit. A broadly heterogenous sample of nonorganic psychotics will be included who will be diagnosed by three alternative diagnostic systems: RDC, Feighner, and DSM-III. In addition, the patients will be rated on the Cannon-Spoor et al. Premorbid Adjustment Scale, the Andreasen positive-negative symptom dimension, chronicity, the Tsuang & Winokur paranoid-hebephrenic distinction, and a behavioral measure of handedness. Handedness of first-degree relatives will also be obtained. A replication study will be done to validate initial findings.
| Kwapil, T R; Hegley, D C; Chapman, L J et al. (1990) Facilitation of word recognition by semantic priming in schizophrenia. J Abnorm Psychol 99:215-21 |
| Chapman, L J; Chapman, J P (1988) Artifactual and genuine relationships of lateral difference scores to overall accuracy in studies of laterality. Psychol Bull 104:127-36 |
| Chapman, J P; Chapman, L J (1987) Handedness of hypothetically psychosis-prone subjects. J Abnorm Psychol 96:89-93 |
