Wible Cynthia G, Han S Duke, Spencer Magdalena H, Kubicki Marek, Niznikiewicz Margaret H, Jolesz Ferenc A, McCarley Robert W, Nestor Paul
Clinical Neuroscience Division, Laboratory of Neuroscience, Harvard Medical School, Boston, MA, USA.
Brain Lang. 2006 Jun;97(3):294-305. doi: 10.1016/j.bandl.2005.11.006. Epub 2006 Jan 18.
Semantic priming refers to a reduction in the reaction time to identify or make a judgment about a stimulus that has been immediately preceded by a semantically related word or picture and is thought to result from a partial overlap in the semantic associates of the two words. A semantic priming lexical decision task using spoken words was presented in event-related fMRI and behavioral paradigms. Word pairs varied in terms of semantic relatedness and the connectivity between associates. Thirteen right-handed subjects underwent fMRI imaging and 10 additional subjects were tested in a behavioral version of the semantic priming task. It was hypothesized priming would be greatest, reaction time fastest, and cortical activation reduced the most for related word pairs of high connectivity, followed by related word pairs of low connectivity, and then by unrelated word pairs. Behavioral and fMRI results confirmed these predictions. fMRI activity located primarily in bilateral posterior superior and middle temporal regions showed modulation by connectivity and relatedness. The results suggest that these regions are involved in semantic processing.
语义启动效应是指在识别或判断一个刺激时，若该刺激之前紧接着出现一个语义相关的单词或图片，其反应时间会缩短，这被认为是由于两个单词的语义关联存在部分重叠所致。在事件相关功能磁共振成像（fMRI）和行为范式中呈现了一项使用口语单词的语义启动词汇判断任务。单词对在语义相关性和关联之间的连接性方面有所不同。13名右利手受试者接受了fMRI成像，另外10名受试者在语义启动任务的行为版本中进行了测试。研究假设，对于高连接性的相关单词对，启动效应最大，反应时间最快，皮层激活减少最多，其次是低连接性的相关单词对，然后是不相关单词对。行为和fMRI结果证实了这些预测。主要位于双侧后颞上回和颞中回区域的fMRI活动显示出连接性和相关性的调节作用。结果表明这些区域参与了语义处理。
