Poster C61, Sunday, March 26, 5:00 – 7:00 pm, Pacific Concourse
Connectivity of the language system revealed by direct brain stimulation during awake neurosurgery
Bram Diamond1, Frank E. Garcea1,2, Benjamin Chernoff1, Raouf Belkhir1, Alex Teghipco1, Susan O. Smith3, Eduardo Navarrete4, Webster H. Pilcher3, Bradford Z. Mahon1,2,3; 1University of Rochester, 2Center for Visual Science, 3University of Rochester Medical Center, 4University of Padova
There is a long history of research in cognitive neuropsychology and cognitive neuroscience that implicates left temporal and frontal regions in language processing. While structural and functional magnetic resonance imaging (MRI) studies have described the connectivity of the language system, it remains poorly understood how disruption of functional connectivity in the language system affects language processing. Here we present case AE, a 26 year-old individual who underwent language mapping during an awake neurosurgical procedure to remove a left supra-Sylvian tumor. Preoperatively, AE was cognitively intact across a number of tasks probing language processing, visuomotor ability, working memory, and semantic memory. AE completed a series of structural (DTI) and functional MRI scans to evaluate language organization and processing in his brain. During AE’s awake neurosurgical procedure, he was asked to name pictures from visual presentation while portions of the left temporal, parietal, and frontal lobes were electrically stimulated; the stimulation points were acquired and registered to the pre-surgical fMRI data. We observe a strong correlation between the functional connectivity to Broca’s area of each point of intraoperative stimulation (connectivity measured with pre-operative imaging), and intraoperative naming latencies on correct naming trials: AE was slower to name pictures when regions that were stimulated expressed stronger functional connectivity to Broca’s area. Control analyses demonstrated that neither functional connectivity between stimulated regions and Wernicke’s area, nor primary motor areas accounted for variance in intraoperative picture naming latencies. These data provide causal evidence of how disruption of language networks affects online processing in picture naming.
Topic Area: LANGUAGE: Lexicon