Fig. 1: Emergence of synergistic brain during the three months around birth.

A The global values of the O-information become significantly more negative at all inspected oscillatory frequencies (Spearman) pointing to emerging synergy towards full term (FT) age. B Relationship between optimally synergistic O-information and the subsystem size (i.e., number of included brain regions) in individual infants (top row) and in averaged age groups (bottom row), colored for the infant’s age at EEG recording. The dots in the bottom plots depict the minimum of O-information curves that reflects the size of subsystems with maximum synergy in the given age group (the optimal “synergistic subsystem”). Note, the systematic growth of the synergistic subsystem with age at all frequencies (optimal system size vs. age: ρ > 0.44, p < 0.001, Spearman), with particularly rapid changes around term age. The glass brain shows all cortical regions (full system) that are color coded according to their anatomical location: frontal (orange), central (magenta), temporal (green), and occipital (black). To find the individual synergistic scaffolds, all possible subsets of nodes (from 3 to 57) were tested. C Relationship (Spearman) between O-information levels and the size of the maximally synergistic subsystem in individual EEG (computed from the curves on the top row in (B); colors code the age at recording). Developmental expansion of the synergistic subsystem and increase of its synergistic capacity are highly correlated (the brain becomes more complex).