Ideation in patients with unilateral or bilateral midline brain lesions.

The hypothesis that persons with left versus right unilateral brain lesions differ in complicated ideational processes is studied in SO 5s with well-localized lesions. On a multiple-discriminant analysis, seven selected Rorschach variables differentiated the left, right, and midline-bilateral groups at the .0001 level. Interpretation of Discriminant 1, Ideation, yields a modus operand! of lefthemisphere Ss which is limited and constricted; of right-hemisphere 5s which is expansive and uncritically innovative. Discriminant 2, Uniqueness of Pathology, indicates that left and right groups not only differ significantly but also are significantly divergent, with the midline group undistinguished on this dimension.