MURAGAKI Yoshihiro
   Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine
   Position   Visiting Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Differential reorganization of three syntax-related networks induced by a left frontal glioma.
Journal Formal name:Brain : a journal of neurology
Abbreviation:Brain
ISSN code:14602156 (Electronic)/00068950 (Linking)
Volume, Issue, Page 137(4),pp.1193-1212
Author and coauthor KINNO Ryuta†, OHTA Shinri, MURAGAKI Yoshihiro, MARUYAMA Takashi, SAKAI Kuniyoshi L.
Publication date 2014/04
Summary The opercular/triangular parts of the left inferior frontal gyrus and the left lateral premotor cortex are critical in syntactic processing. We have recently indicated that a glioma in one of these regions is sufficient to cause agrammatic comprehension. In the present study, we aimed to show how normally existing syntax-related networks are functionally reorganized by a lesion. Twenty-one patients with a left frontal glioma preoperatively performed a picture-sentence matching task, and underwent functional magnetic resonance imaging scans in an event-related design. We established two qualitatively different types of agrammatic comprehension, depending on glioma location. Patients with a glioma in the left lateral premotor cortex had a more profound deficit in the comprehension of scrambled sentences than that of activeand passive sentences. In contrast, patients with a glioma in the opercular/triangular parts of the left inferior frontal gyrus had a more profound deficit in the comprehension of passive and scrambled sentences than that of active sentences. Moreover, we found dramatic changes in the activation patterns in these two patient groups, which accompanied abnormal overactivity and/or underactivity in the syntax-related regions. Furthermore, by examining functional connectivity in the normal brain, we identified three syntax-related networks among those regions, and anatomically visualized connections within individual networks by using diffusion tensor imaging. The first network consists of the opercular/triangular parts of the left inferior frontal gyrus, left intraparietal sulcus, right frontal regions, presupplementary motor area, and right temporal regions. These regions were overactivated in the patients with a glioma in the left lateral premotor cortex only for correct responses, indicating a cognitive change. The second network consists of the left lateral premotor cortex, left angular gyrus, lingual gyrus, and cerebellar nuclei.
DOI 10.1093/brain/awu013
Document No. 24519977
PMID 24519977