Fig. 1.

Two complementary views on brain organization and the corresponding representation of distal effects of focal lesions. (A) A focal lesion (yellow node) on the brain anatomical surface. (B) A schematic description of discrete network parcellation superimposed on a functional connectivity graph-space with nodes and edges. Using this approach to study the effects of focal lesions (yellow node) restricts us to singular networks and assigns connector hubs to one network only. Additionally, distal effects of the lesion are assumed to be equally disruptive for all nodes in the affected network (red nodes). (C) Representing functional connectivity in a continuous manner without sharply defined borders using connectivity gradients. The lesioned node affects all other nodes in the system as a function of the distance from the lesion in connectivity space (dark red to light red). Using this approach does not assume sharp boundaries between functional networks and provides a more realistic model of distant effects of localized lesions.