Subgraphs of functional brain networks identify dynamical constraints of cognitive control
Fig 4
Subgraphs map functional interactions specific to cognitive control tasks.
(A) Relationship between the relative subgraph expression during the Stroop task and the relative subgraph expression during the Navon task. Each point represents relative subgraph expression averaged over subjects, horizontal (vertical) error bars represent standard error of the mean for the Stroop (Navon) task. Generally, relative subgraph expression during the Stroop task is significantly associated with relative subgraph expression during the Navon task (Spearman’s ρ, ρ = 0.97, p = 1.3−7), implying that subgraphs collectively follow similar rules of dynamical expression during the Stroop and Navon tasks. However, individual subgraphs may vary in the amount they are expressed during the Stroop and Navon tasks, which is signified by the perpendicular distance between a subgraph and the shaded gray line with slope equal to one. Using paired t-tests and FDR correction for multiple comparisons, we compare the distribution of relative subgraph expression between Stroop and Navon tasks across subjects. We find greater positive expression during the Navon task than the Stroop task for subgraph B (t27 = 4.4, p = 1.4 × 10−4) and subgraph D (t27 = 2.9, p = 7.0 × 10−3), and we find greater negative expression during the Navon task than the Stroop task for subgraph K (t27 = 5.1, p = 1.4 × 10−5). Thus, the rank of a subgraph in terms of its overall expression relative to other subgraphs is similar between the Stroop and Navon tasks, but its level of expression may be different depending on the task. Specifically, we find subgraphs B and D are more strongly associated with correlated dynamics during the Navon task than the Stroop task, and we find subgraph K is more strongly associated with anticorrelated dynamics during the Navon task than the Stroop task.