Lateral asymmetry in patients with nervous and mental disease. A preliminary study

Hand preference and the performance of thumb-to-finger opposition by the right and left hands were tested in four samples: manic-depressives, schizophrenics, nonpsychotic patients with diseases of the central nervous system and normal control subjects. The schizophrenics and manic-depressives both showed significantly more pure dominance (e.g. right-handed, and superior right thumb opposition) than the normal controls, while the nonpsychotic patients with diseases of the central nervous system showed significantly more cross-dominance (e.g. right-handed, but superior left thumb opposition) than the normal control subjects.