Figure 4. Relationship between within-subject brain variability and behavior after adjusting for age differences across individuals (age was regressed out from all measures).

Color scale and legends are the same as for Figure 3. A) Correlations are arranged in a table where rows represent three within-subject brain variability measures (pre- and post- stimulus PCA and MSE) and columns represent three behavioral measures (cvRT, accuracy and mean RT). Each entry in the table shows a scalp map resulting from interpolated values from single channel correlations between given brain variability measure and given behavior or age. Unstable correlations (where the 95% CI included 0) were set to 0. Colormap corresponds to [−0.7 0.7] range of correlation values. Along with each scalp map of correlations, there is an inset showing a scatter plot representing subject measures for a single channel (electrode O2). Subjects are grouped by color according to age group membership. Estimated value of correlation (r) along with the associated 95% CI is given on top. B) Statistical analysis of brain-behavior correlations adjusted for age. PLS detected one significant pattern of correlations for pre- and post-stimulus PCA dimensionality estimation (p = 0.003, and p = 0.011), and one pattern for MSE that did not exceed conventional statistical thresholds (p = 0.131). Bootstrap analysis of the two significant patterns for PCA showed, however, that the patterns were unstable for most channels (data not shown).