Tumor location and electrode placement. A) Coronal T2-weighted anatomical MRI showing a lesion with increased signal intensity in the right posterior insula marked by an arrowhead. This lesion was subsequently resected and was consistent with a ganglioglioma. B) Superimposed coronal CT and MRI images showing 3 implanted depth electrode strips in the right hemisphere. The top two lines were implanted in the insular cortex and the bottom line was inserted into the hippocampus and parahippocampus. Electrodes I-pIC (inferior posterior insular) and S-pIC (superior posterior insular cortex) were stimulated to investigate insular involvement in the cerebral control of swallowing.