Figure 4.

1/f noise and behavior. A, Greater visual cortical 1/f noise across younger (blue) and older (red) adults predicts lower working memory performance (top). Mediation analyses (bottom) shows that visual cortical 1/f noise statistically mediates age-related visual working memory decline. Although aging is associated with both increased 1/f noise and decreased visual working memory accuracy, and visual cortical 1/f noise predicts accuracy impairments, the relationship between age and accuracy became insignificant after including 1/f noise in the model (bottom r/p value pairs). 1/f noise is also associated with longer RTs (B) and greater RT variability (C); however, it does not act as a mediating variable for either of these RT measures.