Fig. 8.

Results of hierarchical clustering for experiment 1a, resting state (left) and experiment 1b, story comprehension (right). Hierarchical clustering creates a binary tree where branch length (horizontal lines) corresponds to the similarity (here, average correlation across participants) between functional regions of interest (fROIs). The color of the dots on the y-axis represents our a priori assignment of fROIs to networks: multiple demand (MD; blue), language (red), and theory of mind (ToM; green). Above each tree diagram, modularity is plotted for all fROI partitions in the tree. Each point in the modularity plot corresponds to a partition: an imaginary vertical line drawn from a location where two fROIs or clusters of fROIs connect to form a higher-level cluster. The dashed lines represent the points of maximum modularity, which correspond to a partition into networks. During resting state, maximum modularity is at a partition into three clusters: MD (blue lines), language (red lines), and ToM (green lines). All fROIs are correctly assigned to clusters, apart from the right IFG language fROI at rest, assigned to the MD network and the bilateral angular gyrus (AngG) language fROIs which were assigned to the ToM network, despite being defined with the language localizer. During story comprehension, maximum modularity is at a two-partite division: an MD cluster (blue) and a language-ToM cluster (yellow). Within the latter, fROIs mostly remain segregated into language and ToM fROIs, except for the left angular gyrus (AngG) language fROI. See glossary.