Anatomical/axonal basis and plasticity of resting-state fMRI connectivity in an experimental model of corpus callosum transection

Abstract

This study explored the role of anatomical/axonal connections in resting-state fMRI connectivity and the plasticity of resting-state networks. Animal models of complete and partial corpus callosum (CC) transection were studied with rsfMRI in conjunction with intracortical EEG recording and Mn2+ tracing of axonal connections. At post-surgery day 7, resting-state connectivity significantly decreased in the cortical areas whose callosal connections were severed. At post-surgery day 28, disrupted connectivity was partly restored in partial transection group, likely through the spared pathways in remaining CC. These rsfMRI findings were paralleled by EEG recording and. Mn2+ tracing results. These results directly support the primary and indispensable role of anatomical/axonal connections via CC in resting-state fMRI connectivity, and that anatomical connection based resting-state networks can be plastic. (Abstract by ISMRM)