Differential age trajectories of positive and negative affect: further evidence from the Berlin Aging Study.

In cross-sectional and longitudinal samples from the Berlin Aging Study, fellow researchers and I examined performance-based and self-evaluative indicators of functioning in two realms as predictors of individual differences and intraindividual changes in positive and negative affect. Cross-sectional and longitudinal structural equation models suggested that performance-based indicators (level of social involvement and test intelligence) were associated with positive affect, but not with negative affect. Evaluative indicators (self-reported quality of social life and mental fitness) showed stronger relations to negative affect than to positive affect. The present evidence provides an explanation for the differential stability of positive versus negative affect in old age: Positive affect may decline because it requires objective competencies, which seem to decrease in old age. Negative affect may remain stable because it is associated with self-evaluations, which seem to change less with age.