Age effects on executive ability

Heterogeneity of executive tasks has made it difficult to determine whether there are age-related declines in executive functioning. To address this i ssue, 112 individuals, 20-79 years old, took the California Trail Making Te st (CTMT) and the California Stroop Test (CST), subtests of the Delis-Kapla n Executive Function Scale (D. C. Delis, E. Kaplan, & J. H. Kramer, in pres s) that include measurement of component skills embedded in the executive f unction tasks. Multiple regression analyses revealed that after controlling for component skills, age had a significant effect on the executive requir ement of the CST, namely speed on the interference condition. Age did not a ffect switching performance on the letter-number condition of the CTMT. Add itional analyses revealed that age was significantly associated with commis sion of certain types of errors. This study confirms the importance of part ialing out components in the assessment of multidimensional cognitive tasks , particularly when making age comparisons. It also emphasizes specificity over generalizability when examining the impact of age on cognition.