Fourth, it is well recognized that functional connectivity cannot decipher the direction of information flow between regions, where as many anatomical projections which we have based our hypothesis on, are in fact directional in nature. Therefore, the next logical steps would be to test whether directional connectivity models of fMRI such as dynamic causal modeling (DCM) [77] and Granger causality (GC) [78–81] are sensitive to direction-specific anatomical projections at the layer-level.
