Naoki Ikegaya1, Hirotaka Motoi2, Keiya Iijima3, Yutaro Takayama1, Toshimune Kambara4, Ayaka Sugiura5, Brian H Silverstein6, Masaki Iwasaki7, Eishi Asano8. 1. Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan; Department of Neurosurgery, Graduate School of Medicine, Yokohama City University, Yokohama 2360004, Japan. 2. Department of Pediatrics, Graduate School of Medicine, Yokohama City University, Yokohama 2360004, Japan; Department of Pediatrics, Wayne State University, Children's Hospital of Michigan, Detroit, MI 48201, USA. 3. Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan. 4. Department of Pediatrics, Wayne State University, Children's Hospital of Michigan, Detroit, MI 48201, USA; Department of Psychology, Hiroshima University, Hiroshima 7398524, Japan. 5. Department of Pediatrics, Wayne State University, Children's Hospital of Michigan, Detroit, MI 48201, USA. 6. Translational Neuroscience Program, Wayne State University, Detroit, MI 48202, USA. 7. Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Tokyo 1878551, Japan. Electronic address: iwa@ncnp.go.jp. 8. Department of Pediatrics, Wayne State University, Children's Hospital of Michigan, Detroit, MI 48201, USA; Department of Neurology, Wayne State University, Children's Hospital of Michigan, Detroit, MI 48201, USA. Electronic address: easano@med.wayne.edu.
Abstract
OBJECTIVE: To characterize the spatiotemporal dynamics of auditory and picture naming-related cortical activation in Japanese-speaking patients. METHODS: Ten patients were assigned auditory naming and picture naming tasks during extraoperative intracranial EEG recording in a tertiary epilepsy center. Time-frequency analysis determined at what electrode sites and at what time windows during each task the amplitude of high-gamma activity (65-95 Hz) was modulated. RESULTS: The superior-temporal gyrus on each hemisphere showed high-gamma augmentation during sentence listening, whereas the left middle-temporal and inferior-frontal gyri showed high-gamma augmentation peaking around stimulus offset. Auditory naming-specific high-gamma augmentation was noted in the bilateral superior-temporal gyri as well as left frontal-parietal-temporal perisylvian network regions, whereas picture naming-specific augmentation was noted in the occipital-fusiform regions, bilaterally. The inferior pre- and postcentral gyri on each hemisphere showed modality-common high-gamma augmentation time-locked to overt responses. CONCLUSIONS: The spatiotemporal dynamics of auditory and picture naming-related high-gamma augmentation in Japanese-speaking patients were qualitatively similar to those previously reported in studies of English-speaking patients. SIGNIFICANCE: The cortical dynamics for auditory sentence recognition are at least partly shared by cohorts speaking two distinct languages. Multicenter studies regarding the clinical utility of high-gamma language mapping across Eastern and Western hemispheres may be feasible.
OBJECTIVE: To characterize the spatiotemporal dynamics of auditory and picture naming-related cortical activation in Japanese-speaking patients. METHODS: Ten patients were assigned auditory naming and picture naming tasks during extraoperative intracranial EEG recording in a tertiary epilepsy center. Time-frequency analysis determined at what electrode sites and at what time windows during each task the amplitude of high-gamma activity (65-95 Hz) was modulated. RESULTS: The superior-temporal gyrus on each hemisphere showed high-gamma augmentation during sentence listening, whereas the left middle-temporal and inferior-frontal gyri showed high-gamma augmentation peaking around stimulus offset. Auditory naming-specific high-gamma augmentation was noted in the bilateral superior-temporal gyri as well as left frontal-parietal-temporal perisylvian network regions, whereas picture naming-specific augmentation was noted in the occipital-fusiform regions, bilaterally. The inferior pre- and postcentral gyri on each hemisphere showed modality-common high-gamma augmentation time-locked to overt responses. CONCLUSIONS: The spatiotemporal dynamics of auditory and picture naming-related high-gamma augmentation in Japanese-speaking patients were qualitatively similar to those previously reported in studies of English-speaking patients. SIGNIFICANCE: The cortical dynamics for auditory sentence recognition are at least partly shared by cohorts speaking two distinct languages. Multicenter studies regarding the clinical utility of high-gamma language mapping across Eastern and Western hemispheres may be feasible.