Fig. 4.

(Top left) Functional MRI showing increased BOLD activity (shown in yellow and orange) in Broca's area, as well as auditory/Wernicke's area, precentral gyrus, supplementary motor/premotor cortex and prefrontal cortex. ECS (white circles) caused speech arrest in Broca's area, adjacent to increased BOLD activity. (Top right) Small black dots represent electrode contacts of the standard extraoperative subdural grid. Results from extraoperative ECoG-based functional mapping (shown in green) demonstrated increased activity in Broca's area, precentral gyrus, supplementary motor/premotor cortex and postcentral gyrus. (Bottom) Results from intraoperative ECoG-based mapping are shown in red. The diameter of each circle is proportional to the activity under the corresponding electrode contact. The largest circles identify locations that are qualitatively concordant with those from extraoperative ECoG-based and ECS mapping.