Raven's colored Progressive Matrices and intellectual impairment in patients with focal brain damage

To assess the validity of Raven's Colored Progressive Matrices (RCPM) as a measure of intellectual impairment after focal brain damage, we compared the performance of 24 right brain-damaged patients, 24 left brain-damaged patients (10 non-aphasic and 15 aphasic) and 20 controls on the RCPM. In addition to the total, we analyzed the scores obtained on each of the three sets in which the 36 items of the test could be categorized on the grounds of the cognitive ability mainly involved for their solution. The first set, which calls for the identification of sameness, posed special problems to RBD patients. The second set, which involves the principle of symmetry, was selectively failed by aphasic patients. The third set, which is more demanding in terms of analogical and conceptual thinking, was poorly performed by left brain-damaged patients, aphasics as well as non-aphasics. The implications of these findings for the relation of focalized brain damage to intelligence is discussed.