Abstracts

RATIONALE: fMRI language paradigms readily identify frontal language areas but temporal language area activation is inconsistent. We used an auditory based language comprehension task to identify temporal language areas in CPS patients. METHODS: We studied 19 patients (three left handed) aged 12-55 years (mean 25.7), with a confirmed temporal lobe focus using whole brain 1.5T fMRI (EPI BOLD). During the task patients listened to a 6-7 word object description, compared to rest. There were six control/task cycles of 64 seconds each. Data were analyzed with a region of interest analysis from t-maps (t=4). The number of activated voxels was determined in IFG, MFG, and Wernicke's area using a semi-automated program. An asymmetry index (AI) was calculated [(L-R)/(L+R)] for each region. fMRI language laterality was defined as |AI|>0.20 and minimum 3 regional pixels. 12 patients had an intracarotid amytal procedure (IAP). RESULTS: The fMRI auditory comprehension task provided evidence of language lateralization in 17/19 patiets: 16 in temporal & 16 in frontal regions; 15 in both frontal and temporal regions. Left language lateralization was found in 14, in agreement with IAP (7) or surgery (one failed IAP). Two patients had right language dominance in agreement with IAP. One patient had left IAP but mixed dominance with fMRI (LIFG, LMFG, R Wernicke's) also seen in reading and verbal fluency fMRI studies. Two had poor activation (one left IAP). CONCLUSIONS: fMRI auditory based language comprehension paradigms identify frontal and temporal language cortex. They may add to the fMRI armamentarium means to identify temporal receptive language areas which are at risk during surgery. Supported by NINDS KO8-NS1663 & ERB, NINDS