Fig. 4: Environmental enrichment modulates global synergy and local maturity of neuronal activity.

A Developmental trajectories in the global synergy (O-information) in the SC (gray) and FNI (dark red) groups at different frequency bands. Dots indicate group mean values computed at bi-weekly intervals and positioned at their midpoints, with shades depicting standard error of the mean (SEM); asterisks and circles indicate significant group differences (Wilcoxon rank-sum test, uncorrected). The bars on top show the absolute values of the effect size (ES) computed as rank-biserial correlation. The red and blue dots on the X-axis depict age points with the strongest consistent difference across all frequencies, which were selected for further analysis (in (B) and (C)). The green bar depicts period corresponding to normal full-term birth. Note the differences in developmental trajectories: FNI shows steady decrease, whereas SC is characterized by an initial “plateau” until a rapid decline occurs after about 38 weeks of age to reach the levels comparable to the FNI group. B Comparison of SC and FNI groups for O-information minima across different frequencies at the two time points marked in (A) (left, 35 weeks; right, 38 weeks). C Comparison of the optimal synergistic subsystem size for the same time points. In both (B) and (C), individuals' values are shown with dots and the whiskers show mean (circle) and standard deviation (thick line), respectively. D Regional trajectories of local maturation in neuronal activity estimated by functional brain age (FBA) in the SC (gray) and FNI (dark red) groups. The FBA values (dots show infant group means; shade depicts SEM) in the graphs were computed as average of parcels in each cortical region.