Figure 3.

Global structure–function coupling. Bar plot comparing SDI values for each EEG band in (a) and for each HbO and HbR in (c) across conditions, displayed as z-values. A higher absolute z-value indicates a more significant difference between the two groups. A positive z-value suggests that the first group has higher values than the second group (indicating more decoupling), while a negative z-value implies lower values in the first group (indicating more coupling). The red asterisks indicate statistical significance (p < 0.05). (b–d) Illustration of SDI distribution across ROIs and subjects for each EEG band and each hemoglobin for fNIRS, respectively, in both resting state and task conditions. (e) Comparison between modalities (each band with each hemoglobin) for both resting state and task, represented as z-values.