Task Encoding across the Multiple Demand Cortex Is Consistent with a Frontoparietal and Cingulo-Opercular Dual Networks Distinction

Functional connectivity between MD ROIs. a, Fisher-transformed correlation values (Z) between all ROIs. Gray squares above the diagonal represent nonsignificant correlations. b, Mean connectivity strength within each subnetwork and between the two subnetworks. Connections between hemispheric homologs (e.g., DLPFC–DLPFC) were not included. Significant differences at the level p < 0.05 are shown. c, Graphs resulting from a threshold of Z > 0.2 and Z > 0.5. Yellow nodes and lines represent the FP ROIs and the surviving connections between them. Red nodes and lines represent the CO ROIs and the surviving connections between them. Purple lines represent surviving connections between the two subnetworks. The smaller correlation matrix is the thresholded and rescaled version of the matrix shown in a. All values below the threshold are shown as dark blue as given by the color scale.

Functional connectivity of residual activity between MD ROIs. a, Mean connectivity within each subnetwork and between the two subnetworks. Significant differences at the level p < 0.05 are shown. b, Graph resulting from a threshold of Z > 0.3. For conventions, see Figure 2.

Task decoding across the multiple demand ROIs. The MD ROIs are shown on the central brain rendering. Results for FP ROIs are shown on the left and those for CO ROIs on the right. Within each ROI, each colored matrix shows mean CA for all task pairs averaged across participants. The bottom left of each matrix shows all CAs; the top right shows the same CAs but with nonsignificant CAs greyed out.

Task decoding in FP and CO subnetworks. Blue indicates similar task decoding; orange dissimilar task decoding. Lighter colors indicate CO ROI and darker colors FP ROIs. a, Mean classification accuracy across subjects associated with each ROI separately for similar and dissimilar tasks. CO ROIs are shown on the left, FP ROIs on the right. b, Mean classification accuracies after averaging over CO and FP ROIs.

Univariate activity across the MD ROIs. a, Mean task-related change in β values relative to baseline in each of the MD ROIs across participants. Results show that all regions were more active when engaged on the task, but there is no clear difference in activation between the two subnetworks. b, t-values from a two-tailed, paired t test of β values shown in a against the implicit baseline across participants. Similar t-values give an indication that the signal-to-noise ratio of the univariate signal is comparable across the two subnetworks.