左侧背外侧前额叶在汉语认知冲突加工中的作用——一项经颅直流电刺激研究

The Role of the Left Dorsolateral Prefrontal Cortex in Chinese Cognitive Conflict Processing—A Transcranial Direct Current Stimulation Study

摘要: 本研究采用经颅直流电刺激(tDCS)技术，探讨左侧背外侧前额叶(DLPFC)对汉语认知冲突的调控作用。26名健康被试在阳极刺激与伪刺激条件下完成Flanker任务、语义冲突任务及情绪冲突任务。结果显示，阳极刺激显著缩短不一致条件下的整体反应时，其中语义冲突的效率提升最为显著，情绪冲突任务中一致与不一致条件的加工均得到优化，而Flanker任务的刺激敏感性较弱。进一步分析表明，DLPFC激活可能通过增强目标导向控制及认知–情绪交互，显著提升情绪冲突任务的正确率；神经机制上，DLPFC既参与额顶通路等通用认知控制网络，又可能通过语言网络整合与情绪调控等任务特异性路径适应不同冲突需求。情绪一致条件下的促进效应提示，DLPFC可能通过隐性监控机制协调情绪与认知资源分配。本研究为DLPFC在语言与情绪冲突中的功能分化提供因果性证据，并从行为层面为认知空间理论的表征重构机制补充实验依据。

Abstract: This study employed transcranial direct current stimulation (tDCS) to investigate the regulatory role of the left dorsolateral prefrontal cortex (DLPFC) in Chinese cognitive conflict processing. Twenty-six healthy participants completed the Flanker task, semantic conflict task, and emotional conflict task under anodal stimulation and sham stimulation conditions. Results showed that anodal stimulation significantly shortened overall reaction times under incongruent conditions, with the most pronounced efficiency improvement observed in the semantic conflict task. In the emotional conflict task, processing under both congruent and incongruent conditions was optimized, whereas the Flanker task showed weaker sensitivity to stimulation. Further analysis indicated that DLPFC activation may significantly enhance accuracy in the emotional conflict task by strengthening goal-directed control and cognitive-emotional interactions. At the neural mechanism level, the DLPFC not only participates in general cognitive control networks such as the fronto-parietal pathway but also adapts to different conflict demands through task-specific pathways, such as language network integration and emotional regulation. The facilitative effect under emotionally congruent conditions suggests that the DLPFC may coordinate the allocation of emotional and cognitive resources through implicit monitoring mechanisms. This study provides causal evidence for the functional differentiation of the DLPFC in linguistic and emotional conflicts and supplements experimental support for the representational reorganization mechanism of cognitive space theory at the behavioral level.