A Novel Atlas of Human Cerebral Cortex based on Extrinsic Connectivity

International audienceCurrent theories hold that the human cortex can be subdivided in anatomically and functionally distinct regions, from which interactions cognition arises. In these interactions the long-range axonal connectivity, namely extrinsic connectivity, plays a fundamental role (Passingham et al., 2002). Hence, parceling the cortex taking into account its extrinsic connectivity can help to understand brain’s internal organization. However, current brain atlases are based on cytoarchitecture (Brodmann, 1909) or anatomical landmarks (Desikan et al., 2006), which do not necessarily reflect brain’s connectivity. Even modern approaches, like that of Glasser et al. (2016) did not include connectivity information on their building process. Using such parcellations on studies involving connectivity could introduce a bias, leading to erroneous connections and conclusions. In Gallardo et al. (2016) we presented a hierarchical clustering based technique to parcellate the whole cortex based on its extrinsic connectivity. In this work, we show the consistency of our technique. Then we use it to obtain a novel cortical 55 parcels parcellation based on the extrinsic connectivity of 138 subjects from the Human Connectome Project (HCP). Experiments show that several of our extrinsic parcels are closely related to brain functionality