Koeda M, Takahashi H, Yahata N, Matsuura M, Asai K, Okubo Y, Tanaka H
Department of Bioinformatics, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
Methods Inf Med. 2007;46(2):247-50.
In our previous functional magnetic resonance imaging (fMRI) study, we determined that there was distinct left hemispheric dominance for lexical-semantic processing without the influence of human voice perception in right-handed healthy subjects. However, the degree of right-handedness in the right-handed subjects ranged from 52 to 100 according to the Edinburgh Handedness Inventory (EHI) score. In the present study, we aimed to clarify the correlation between the degree of right-handedness and language dominance in the fronto-temporo-parietal cortices by examining cerebral activation for lexical-semantic processing.
Twenty-seven normal right-handed healthy subjects were scanned by fMRI while listening to sentences (SEN), reverse sentences (rSEN), and identifiable non-vocal sounds (SND). Fronto-temporo-parietal activation was observed in the left hemisphere under the SEN - rSEN contrast, which included lexical-semantic processing without the influence of human voice perception. Laterality Index was calculated as LI = (L - R)/(L + R) x 100, L: left, R: right.
Laterality Index in the fronto-temporo-parietal cortices did not correlate with the degree of right-handedness in EHI score.
The present study indicated that the degree of right-handedness from 52 to 100 in EHI score had no effect on the degree of left hemispheric dominance for lexical-semantic processing in right-handed healthy subjects.
在我们之前的功能磁共振成像（fMRI）研究中，我们确定在右利手健康受试者中，词汇语义处理存在明显的左半球优势，且不受人类语音感知的影响。然而，根据爱丁堡利手量表（EHI）评分，右利手受试者的右利手程度在52至100之间。在本研究中，我们旨在通过检查词汇语义处理的脑激活情况，阐明右利手程度与额颞顶叶皮质语言优势之间的相关性。
27名正常右利手健康受试者在听句子（SEN）、倒序句子（rSEN）和可识别的非语音声音（SND）时接受fMRI扫描。在SEN - rSEN对比下，左半球观察到额颞顶叶激活，其中包括不受人类语音感知影响的词汇语义处理。计算利手指数，公式为LI =（L - R）/（L + R）×100，L：左，R：右。
额颞顶叶皮质的利手指数与EHI评分中的右利手程度不相关。
本研究表明，EHI评分中52至100的右利手程度对右利手健康受试者词汇语义处理的左半球优势程度没有影响。
