Analysis of individual variability among older adults on the Stroop Color Word Interference Test

The present study examines systematic variation in the pattern of response to the Stroop test among a sample of older adults (N = 41), as well as the extent to which various configural patterns of response are related to other individual difference factors. Pattern analysis identified four reasonably prototypic patterns of performance. Three significant discriminant functions, capable of differentiating the four response patterns, were significantly and uniquely related to age, level of cautiousness, and verbal intelligence, respectively. The analyses suggest that performance on the Stroop test is multidimensional with significant variation among older adults, and that different components of performance are differentially related to unique individual difference variables. The findings reinforce the importance of recognizing and understanding the nature of individual variation among elderly individuals in aging research.