Relational Thinking in Later Adulthood

The research addressed the role of relational processing capacity in cognitive aging focusing on (a) age-differences in complex relational processing, (b) the domain-generality of complex relational processing, and (c) associations of complex relational processing with other processes. Participants were 125 adults in three groups with mean ages of 30.55 (younger), 53.43 (middle), and 74.41 years (older). Each relational processing task (sentence comprehension, n-term premise integration, Latin square) included items at three complexity levels. Accuracy was lower on more complex items and relational complexity had a greater effect in the older group. Confirmatory factor analyses confirmed a single complex relational processing factor, consistent with a domain-general capacity. Relational processing was related to other executive processes. This relationship was stronger in the older than younger and middle groups, possibly reflecting dedifferentiation or neural noise. In structural models with planning (Tower of London) and class reasoning as outcome variables, complex relational processing had a significant impact (beta = .455, p < .001 and beta = .661, p < .001. respectively) over and above age. processing speed, working memory, task switching, response inhibition, and Stroop interference. In the structural model with fluid intelligence (matrix reasoning) as the outcome variable, age had a significant impact (beta = -.222, p < .001), over and above all other variables, suggesting that the processes underpinning age-related declines in matrix reasoning are more diverse than those assessed in the current research. Complex relational processing is an important factor in cognitive aging, possibly reflecting its reliance on prefrontal brain regions.