Determining the topography of interhemispheric fibres in the human corpus callosum (CC) between the primary motor cortices with a combined fMRI/DTI-fibretracking prodecure

Background: In the rhesus monkey, previous anatomical studies localized interhemispheric connections between the primary motor cortices (M1) into the anterior segment of the body of the CC. In contrast, in the human CC, there is indirect evidence from transcranial magnetic stimulation (TMS) studies that interhemispheric connections between M1 run in the posterior half of the callosal body. However, exact topography and somatotopy of these fibres within the human CC have not yet been defined. Here, we determine the topography and somatotopy of callosal fibres connecting different body representations (hand, foot)…