Research Paper Volume 13, Issue 3 pp 3218—3238

Brain microstructure mediates sex-specific patterns of cognitive aging

Mediation of age effects on cognitive function by microstructure for women and men. Direct (blue) and indirect (red) effects of age (coefficient [95% confidence interval]) are shown for cognitive scores mediated by microstructure. Coefficients for effects of age on RSI metrics, and effects of RSI metrics on cognitive score are provided. For ease of interpretation, RSI scores were converted to a similar order of magnitude as age and cognitive scores by multiplying raw RSI scores (range 0-1) by 100 (converted range 0-100). Coefficients are unstandardized and reflect the magnitude of change in RSI metric (or cognitive score) per year of age (or 1/100 unit increase in RSI metric). Data are shown for models in which total and indirect effects are significant at p

Figure 4. Mediation of age effects on cognitive function by microstructure for women and men. Direct (blue) and indirect (red) effects of age (coefficient [95% confidence interval]) are shown for cognitive scores mediated by microstructure. Coefficients for effects of age on RSI metrics, and effects of RSI metrics on cognitive score are provided. For ease of interpretation, RSI scores were converted to a similar order of magnitude as age and cognitive scores by multiplying raw RSI scores (range 0-1) by 100 (converted range 0-100). Coefficients are unstandardized and reflect the magnitude of change in RSI metric (or cognitive score) per year of age (or 1/100 unit increase in RSI metric). Data are shown for models in which total and indirect effects are significant at p<0.05. (ATR, anterior thalamic radiation; BDR, Buschke delayed recall; CC, corpus callosum; F major, forceps major; IF, isotropic free water; HI, hindered isotropic; RI, restricted isotropic; VRD, visual reproduction delayed recall.