APPLYING BRINLEY PLOTS TO INDIVIDUALS - EFFECTS OF AGING ON PERFORMANCE DISTRIBUTIONS IN 2 SPEEDED TASKS

This article describes the application of Brinley plots to performance distributions from 2 speeded tasks, namely, letter coding and visual search. Ss were aged either 60 years (n = 111) or 75 years (n = 111). Response times within each age group were ranked and then plotted against each other so that the best 60-year-old was paired with the best 75-year-old, and so on. For both tasks, linear fits to the functions were almost perfect, with slopes greater than 1 and with negative intercepts. Additive and multiplicative models of aging were rejected in favor of a general linear model, with different parameters for the letter coding and visual search tasks.