Spatial Precision of Intra- and Interhemispheric Functional Connectivity in the Human Brain

Abstract

A large body of research has focused on understanding the properties of the functional cortical connectivity in brain networks, such as measures of connection strength and directedness. However, less is known about the spatial precision underlying these connections. To assess this dimension of network organization, we combined multiscale surface-constrained fMRI with a novel network analysis approach designed to quantify the precision of functional connectivity during a sensorimotor task. We show that functional connections within prefrontal areas of both hemispheres are less spatially precise, i.e., occur between comparatively larger neuronal clusters than in sensorimotor areas, consistent with the specialization of prefrontal regions for information integration. Unexpectedly, interhemispheric connections were more precise than intrahemispheric ones, possibly again reflecting different requirements for information integration in these basic connectivity systems of the human brain. Therefore, the analysis of spatial precision adds an intriguing dimension to the characterization of functional and dysfunctional brain networks.