Department of Psychology, South China Normal University, Guangzhou, China.
Brain Res. 2012 Feb 27;1440:56-64. doi: 10.1016/j.brainres.2011.11.060. Epub 2011 Dec 7.
Using event-related functional MRI, we examined the involvement of the left inferior frontal gyrus (LIFG) in explicit and implicit semantic processing of Chinese sentences. During scanning, Chinese readers read individually presented normal sentences with a contextually expected or unexpected target noun and were asked to perform an explicit or implicit semantic task (semantic or syntactic violation judgment). The conjunction analysis of the two tasks revealed LIFG as the critical brain region for semantic integration. Further, a cross-task comparison showed more extensive activations for the expectancy effect in the explicit task than in the implicit task in regions including bilateral anterior cingulate cortex/dorsolateral prefrontal cortex, left middle temporal gyrus, and right inferior frontal gyrus. These results indicate that LIFG is responsible for the integration process per se and that other brain regions observed in previous studies using explicit semantic tasks may be due to task-induced generic processes (e.g., cognitive control).
使用事件相关功能磁共振成像，我们研究了左额下回（LIFG）在中文句子的显性和隐性语义处理中的作用。在扫描过程中，中文读者单独阅读带有语境预期或意外目标名词的正常句子，并被要求执行显性或隐性语义任务（语义或句法违反判断）。两个任务的联合分析揭示了 LIFG 是语义整合的关键脑区。此外，跨任务比较显示，在显性任务中，预期效应的激活范围比隐性任务更广，包括双侧前扣带皮层/背外侧前额叶、左颞中回和右额下回。这些结果表明，LIFG 负责整合过程本身，而在之前使用显性语义任务的研究中观察到的其他大脑区域可能是由于任务诱导的通用过程（例如，认知控制）所致。
