MURAGAKI Yoshihiro    Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine    Position   Visiting Professor
Language	Japanese
Title	The effect of a glioma in the left frontal regions associated with syntactic processing: Two distinct networks revealed by fMRI
Conference	Neuro2010
Conference Type	International society and overseas society
Presentation Type	Poster notice
Lecture Type	General
Date	2010/09/04
Society abstract	神経化学 49(2-3),743 2010
Summary	In our previous functional magnetic resonance imaging (fMRI) study, we used a picture-sentence matching task with different sentence types and demonstrated that the left lateral premotor cortex (L. LPMC) and the left opercular and triangular parts (L. F3op/F3t) of the inferior frontal gyrus (IFG) were selectively involved in syntactic processing (Human Brain Mapping 29, pp. 1015-1027). Using the same paradigm, we have recently found that a glioma in L. F3op/F3t or L. LPMC is sufficient to cause agrammatic comprehension (Brain and Language 110, pp. 71-80). The present study is conducted to clarify the individual roles of these two syntax-related regions in the language network by examining modified cortical dynamics depending on the glioma location in the left frontal cortex. We examined 21 patients with a glioma in L. F3op/F3t, L. LPMC, and other left frontal regions, as well as normal controls. The patients preoperatively underwent a high-resolution 3D-MRI for the identification of the glioma location, and behavioral data of the task were obtained from each group. Using fMRI, the cortical activity was estimated by the comparison between the conditions of sentences with or without the two-argument relationships (FDR corrected, p < 0.05). The normal controls and other patients showed clearly left-lateralized activations in LPMC, IFG, and temporal regions. Compared with these groups, the L. F3op/F3t-damaged patients showed enhanced activations in L. LPMC and L. angular gyrus, as well as suppressed activations in the left frontal and temporal regions, whereas the L. LPMC-damaged patients showed enhanced activations in L. F3op/F3t and various regions including the right hemisphere. Moreover, these modulation patterns of activations were independent of the associated behavioral changes. These results suggest the existence of two distinct networks involving either L. F3op/F3t or L. LPMC, as well as the co-inhibitory network between these two regions.