Aging-related declines occur in many different domains of cognitive function during middle and late adulthood. However, whether a global dimension underlies individual differences in changes in different domains of cognition and whether global genetic influences on cognitive changes exist is less clear. We addressed these issues by applying…

Previous analyses have identified a genetic contribution to the correlation between declines with age in processing speed and higher cognitive abilities. The goal of the current analysis was to apply the biometric dual change score model to consider the possibility of temporal dynamics underlying the genetic covariance between aging trajectories…

Scanator is an extremely valuable tool in the functional analysis of qualitative stability in text building behavior during writing. Scanator also allows for a detailed investigation of subtle changes emerging in the structural relations of emergent novelties. This study focused on the extension of the application of Scanator to one pair of…

Collected data on twins' performance on 13 cognitive variables measured three times at three-year intervals. Twins were monozygotic or dizygotic pairs reared together or apart and were in six cohorts ranging in age from 41 through 84 years. Found stable mean cognitive performance across time on eight measures for the younger cohorts, and…