The relationship between perceptual structure and individual differences in cognitive ability was studied through a computerized inductive reasoning task performed by 100 college undergraduates at Cleveland State University (Ohio). Measures included two psychometric tests and a set of four computerized cognitive tasks. Two components of perceptual structure were defined and measured: intrastimulus, and interstimulus dimensional structure. Intrastimulus (within stimulus) structure was a measure of individual stimulus complexity. Interstimulus structure was a measure of relationships between two or more multidimensional stimuli. Within interstimulus structure, two separate component structures were identified: amount and form. Amount was the quantitative component, a measure of the information load of the matrix. Form was the relational component, and reflected a level of predictability among stimulus dimensions in the matrix. Results indicate that changing dimensional structure between stimuli was an important factor in the prediction of individual differences in intelligence. Separate parameters of interstimulus form and amount were identified as independent predictors of individual differences in ability; interstimulus form was most highly related to individual differences in general cognitive ability. Results support the structural model of F. L. Royer (1978) and are consistent with interpretations of C. E. Spearman's (1923) qualitative model of mental ability as a model of perceptual processing. Two tables, three figures, and one appendix amplify the study. There is a 60-item bibliography. (Author/SLD)