Functional Topography of Human Corpus Callosum: An fMRI Mapping Study
Figure 7
Callosal BOLD effect evoked by visual stimulation in control subjects. (a) Activation was evoked by visual stimuli presented to the CVF (subject E.N.), with a BOLD effect being consistently observed bilaterally in area VI ((a)1) and in the posteriormost part of the splenium ((a)2, green arrow). Callosal fibers arising from an ROI selected in area VI ((a)1, green circle) cross the CC through the splenium, where the activation focus is found ((a)3, yellow arrow). (b) Activation evoked by visual stimuli presented to the lateral VF (subject A.Q.). Cortical activation was present only on the contralateral side ((b)1) in a slightly more posterior splenial region ((b)2, green arrow). Callosal fibers arising from an ROI selected in area VI ((b)1, green circle) cross the CC through the splenium, where the activation focus is observed ((b)3, yellow arrow). On DTI images, a thin white line demarcates the CC. Numbers on each brain represent the Talairach coordinates (, , ) of each focus (green arrows). Left hemisphere on the right.
