PSYCHOMETRIC INTELLIGENCE AND VISUAL FOCUSED ATTENTION - RELATIONSHIPS IN NONSEARCH TASKS

The research reported in this article was designed to explore the relation between visual focused attention and general intelligence (g). In two experiments, adults differing in g were given response-competition tasks (e.g., B.A. Eriksen & Eriksen, 1974). In the first experiment, a central target letter appeared in each stimulus display either alone or flanked on each side by a neutral, compatible, or incompatible letter. In the second experiment, a line (vertical or horizontal) was presented in each stimulus display, either alone or flanked on each side by a neutral, compatible, or incompatible form. In both experiments, subjects were instructed to respond only to the central stimulus or target and to ignore the flanking stimuli that might appear simultaneously with the target. The results of both experiments were similar. The analyses of the mean and median RTs showed the typical effects of the flankers: Subjects were unable to restrict their attention to the central target stimulus and exclude the flanking stimuli from processing. No significant main effect or interaction of intelligence was found with mean and median RTs as dependent variables. Analyses of the shape of the RT distributions were also made by taking the ex-Gaussian distribution as model. These analyses indicated that, for all stimulus conditions in both experiments, tau-one of the parameters of the ex-Gaussian model-was systematically lower for high-g subjects than for low-g subjects. However, because no interaction between g and stimulus factors reached any significant level, differences in tau Cannot be interpreted as differences in attentional efficiency. In short, the results indicate that psychometric intelligence does not tap visual focused attention.