Stability and change in typical intellectual engagement in old age across 5 years

Typical intellectual engagement (TIE) is related to cognitive development across the life span, but the development of TIE itself has not been examined. In the present study, structural change, differential change, absolute change, stability of divergence, and the generality of changes in the 4 TIE-factors abstract thinking, problem solving, reading, and intellectual curiosity across 5 years were examined in older adults.

Data came from the Zurich Longitudinal Study on Cognitive Aging. Two hundred and thirty-three individuals, 73 years on average at first measurement occasion (2005), were reassessed after 5 years. Confirmatory factor analyses and latent change score models were applied.

Factor covariances were equal across time, implying structural stability. Coefficients for differential stability were around .80, implying small significant mean-level changes for problem solving and intellectual curiosity. No changes in divergence emerged. Change correlations between the factors were in the medium to large range.

Across 5 years, TIE remained relatively stable on a group level. However, pronounced interindividual differences emerged. Also, although the changes in factors shared a substantial amount of variance, the development of the factors was not completely parallel.