Localization of motor speech area by functional MRI during word generation

J Korean Neurol Assoc > Volume 16(5); 1998 > Article

Journal of the Korean Neurological Association 1998;16(5): 654-659.

단어생성시 기능적 자기공명영상을 통한 운동 언어중추의 국소화

정 상욱, 송 인찬*, 이 경민, 이 상건, 장기현*

서울대학교 의과대학 신경과학교실, 진단방사선과학 교실*

Localization of motor speech area by functional MRI during word generation

Sang-Wuk Jeong M.D., In-Chan Song* Ph.D., Kyung-Min Lee M.D., Sang-Kun Lee M.D.,Kee-Hyun Chang* M.D.

Department of Neurology and Radiology*, Institute of Radiation Medicine* Seoul National University College of Medicine

Abstract

Background: Until recently lateralization or localization of language area was possible only by electrical stimulation or Wada test. We describe here a convenient and noninvasive method of language localization with functional magnetic resonance image (MRI). Method: Twelve healthy right-handed Korean young volunteers (M:F=9:3, mean age: 24 years) were recruited for this study. We collected brain activation image of 6 slice using gradient echo EPI (Echo-planar imaging) during 8 sets of resting and activation periods. During resting periods, each of 10 Korean nouns composed of two to four syllables was shown continuously every 3 seconds and the subjects were required to simply read the words. The activation task was to generate words as many as possible beginning with the same initial syllable seen on screen without any movement. The data were analyzed using SPM (statistical parametric mapping) and the activated signals were overlayed on a T1-weighed image. Result: The activated areas were observed in the perisylvian areas including inferior frontal gyrus and middle superior temporal gyri in 9 subjects. (left in 7, right in 2) Another one subject showed nonsignificant activation in left pre-& postcentral gyrus. The remaining two subjects showed only motion artifacts. Therefore, except motion artifact we localized motor speech areas in 9 of 10 subjects.
Conclusion: Activation of motor speech area is observed by functional MRI using EPI technique efficiently, quickly and noninvasively. Such functional mapping may have value for the neurosurgical planning. Key words: Language localization, functional MRI, Perisylvian areas