The neuropsychological application of the Ruff 2 and 7 Selective Attention Test as a measure of visual selective attention was investigated. The instrument was constructed as a paper-and-pencil approach to evaluate sustained attention utilizing different distractor conditions in the study of voluntary or intentional aspects of attention. Four patient groups with cerebral lesions confined to either the right or left anterior or left or right posterior region ( ns = 8, 8, 8, 6) were studied. Patients with right-hemispheric lesions showed a greater over-all reduction in processing speed independent of the serial or parallel processing mode in comparison to individuals with left-sided lesions. Furthermore, as predicted, the two groups with anterior brain damage showed a larger discrepancy between serial and parallel processing modes than patients with posterior lesions. Specifically, the right frontal cases showed the greatest differential of accuracy on the serial and parallel tasks.