This study used a neuropsychologically-based intelligence theory to explore gender differences in cognitive processing in college students. A more modern approach to the measurement of intelligence is instrumental, since traditional intelligence tests have been unable to explain the significant gender discrepancy that exists in academic performance, brain functioning, and special education placement. This study used 16 experimental tasks that are based on the planning, attention, simultaneous and successive (PASS) cognitive processing theory. Studies in the last 10 years using the PASS theory have found that adolescent girls have superior cognitive processing abilities in the areas of planning and attention. The gender differences found in processing abilities may not be related to environmental factors, but to different rates of cortical growth, or the hormonal effects of earlier puberty. In this study, multivariate analysis of variance indicated female superiority in two measures of attention. Females also demonstrated a marked global difference in attention (P <.06). While females also obtained a higher mean score on planning ability, the difference was not found to be significant. These results seem to indicate that the adolescent female superiority in planning may be a function of earlier prefrontal lobe development, and the planning gender differences diminish as we progress into adulthood. However, the finding that females are superior in attention processing ability seems consistent from adolescence into adulthood. Implications of these results for neuropsychological assessment, psychoeducational assessment, and treatment interventions are discussed.