目的 利用事件相关功能磁共振成像(functional MRI)技术比较中文双字真词与假词的认知加工的脑机制。方法 14名大学生在MR扫描过程中执行词汇判断任务,用视觉方式随机呈现120个双字词,其中真、假词各60个。结果 真、假词的判断激活了相似的包括双侧额下回,颞中回,梭状回和舌回,双侧缘上回,丘脑等区域。其中,左侧额下回(BA44/45区)在假词条件下的激活强度显著高于真词。结论 左额下回可能与语音存贮、行为选择或调控注意有关。
Objective To contrast the neural substrate of lexical processing of Chinese real words and pseudowords using event-related functional magnetic resonance imaging (fMRI). Methods Fourteen university students were instructed to perform a visual lexical decision task while being scanned with a 1.5T MRI scanner with a list of randomly intermixed real and pseudo Chinese two-character (or two-syllable) words. Results Processing of real words and pseudowords activated a highly comparable neural network, including bilateral inferior frontal gyrus (IFG), middle temporal gyrus, fusiform gyrus, lingual gyrus, supramarginal gyrus, and thalamus. However, left inferior frontal gyrus (BA 44/45) was significantly more activated in pseudo word processing than in real word processing. Conclusion This result supports that the left IFG maybe related with the phonological information storage, behavior chosen or attention modulation.