Abstract
A fundamental hypothesis in neuroscience is that connectivity mirrors function at a fine spatial grain across the cortex. Previous research supports this hypothesis for the human brain, by demonstrating that the degree of voxelwise face-selectivity in the fusiform gyrus of individual subjects can be predicted from that voxel's connections to the rest of the brain (its unique connectivity fingerprint), measured through diffusion-weighted imaging (DWI; Saygin et al. 2012). Here we asked whether resting-state functional connectivity (fcMRI) can also predict face-selectivity in the fusiform gyrus, and whether structural or functional connectivity fingerprints also predict other visual selectivities in multiple extrastriate cortices. We found that both fcMRI and DWI connectivity predicted face selectivity in the fusiform more accurately than did a group analysis of face selectivity from other subjects. Prediction accuracies from DWI connectivity were slightly but significantly better than predictions from fcMRI connectivity for the fusiform gyrus. A direct comparison of the subset of connections that best predicted face-selectivity revealed that DWI and fcMRI connectivity fingerprints for function were generally quite similar, especially for the top predictors, although differences existed among weaker predictors. We performed similar comparisons of DWI and fcMRI connectivity fingerprints for other extrastriate regions and for body, object, and scene perception. These data provide converging evidence from both DWI and fcMRI that i) connectivity and function are tightly linked at a voxelwise scale in extrastriate cortex in humans, and ii) functionally-selective voxels can be predicted from either diffusion or resting functional data alone. These results also raise the possibility that connectivity fingerprints direct the functional specialization of cortex in development. Finally, this work has practical relevance for researchers and clinicians, by providing a method to infer functional brain maps from structural images alone in individuals who cannot be functionally scanned (e.g. comatose subjects, or sleeping infants).
Meeting abstract presented at VSS 2014