Vision and intelligence at age 83 in the Lothian Birth Cohort 1921

The extent to which visual function, measured as near and distant visual acuity and contrast sensitivity, is correlated with concurrently measured cognitive function and prior intellectual ability was investigated in a narrow age range group known as the Lothian Birth Cohort of 1921 (LBC1921). Participants were aged ~ 83 years at the time of testing (N = 321). A well-fitting structural equation model highlighted a significant contribution of a latent visual trait to a general fluid intelligence factor in old age, independent of the contribution from childhood intelligence. Additionally, childhood intelligence made a significant contribution to the general visual factor in old age. However, the model fitted equally well when the fluid intelligence factor is assumed to be a cause of the visual function latent trait, in which case childhood intelligence does not significantly influence vision in old age. We discuss these results with respect to four possible mechanisms by which vision and cognition can come to be correlated over the lifecourse.

Research highlights
► Visual function contributes to cognitive ability in old age, independently of prior intelligence.
► Higher childhood intelligence was associated with better visual function in old age.
► It is also possible that intelligence in old age contributes to better visual function.