Shared age-related influences on cognitive and noncognitive variables.

Analyses of new data and of previously published data were conducted to examine the degree to which age-related variance was shared across cognitive and noncognitive variables and to investigate possible alterations in the composition of a factor common to all variables as a function of age. The results indicated that measures of visual acuity, grip strength, and blood pressure shared age-related variance with measures of perceptual speed, episodic memory, spatial visualization, and inductive reasoning. However, although the cognitive variables shared similar amounts of variance in age-restricted and age-partialed analyses, the variance shared between cognitive and noncognitive variables was substantially reduced after controlling the influence of age.