CAS Key Laboratory of Behavioral Science, Institute of Psychology, Beijing 100101, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing 100049, China.
CAS Key Laboratory of Behavioral Science, Institute of Psychology, Beijing 100101, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing 100049, China.
Neuropsychologia. 2018 Mar;111:36-44. doi: 10.1016/j.neuropsychologia.2018.01.010. Epub 2018 Jan 12.
Using functional magnetic resonance imaging (fMRI), we investigated the effects of context features on the involvement of the working memory (WM) system during discourse comprehension. During the fMRI scan, participants were asked to read two-sentence discourses in which the topic of the second sentence was either maintained, or was shifted from, the topic of the first. Changes in the level of coherence between the two sentences as well as context length were also investigated across discourse items. The WM system was identified with a verbal N-back task. Analysis of the reading comprehension task revealed that within the WM system, stronger activation in the left inferior frontal gyrus corresponded with increased bridging coherence demands between sentences, while greater activation in the left inferior and middle frontal gyri, bilateral superior frontal gyri, and bilateral inferior parietal lobules corresponded with increased context length. Topic variation showed no effect on activation of the WM system. These results provide new insights into understanding how different levels of context features modulate activation of the subcomponents of the WM system and indicate a role for the left inferior frontal gyrus as a core component of the WM system supporting discourse processing.
我们使用功能磁共振成像（fMRI）技术研究了语境特征对语篇理解过程中工作记忆（WM）系统参与程度的影响。在 fMRI 扫描过程中，要求参与者阅读两句式语篇，第二句的主题要么与第一句的主题保持一致，要么从第一句的主题转移。我们还研究了跨语篇项目的句子间连贯性水平和语境长度的变化。WM 系统采用言语 N-back 任务来识别。对阅读理解任务的分析表明，在 WM 系统中，左额下回更强的激活与句子间桥接连贯性要求的增加相对应，而左额下回和中回、双侧额上回以及双侧顶下小叶更强的激活与语境长度的增加相对应。主题变化对 WM 系统的激活没有影响。这些结果为理解不同层次的语境特征如何调节 WM 系统子成分的激活提供了新的见解，并表明左额下回作为支持语篇处理的 WM 系统核心组成部分的作用。
