Chen Tingting, Wang Huihui, Wang Xin, Zhu Chunyan, Zhang Lei, Wang Kai, Yu Fengqiong
School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China; Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental Health, Anhui Province, China; Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders, Hefei, China; Anhui Mental Health Center, Hefei, China.
School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, China.
Int J Psychophysiol. 2021 Apr;162:34-39. doi: 10.1016/j.ijpsycho.2021.01.014. Epub 2021 Jan 23.
A number of functional magnetic resonance imaging studies have shown that the dorsolateral prefrontal cortex (dlPFC) is a critical brain region for response inhibition. However, how it exerts this function remains unclear. This study investigated whether stimulating the right dlPFC by transcranial direct current stimulation (tDCS) affects performance on stop signal task.
A total of 92 healthy subjects were enrolled in the study and randomly divided into three groups. The anode group received anodal stimulation over the right dlPFC and cathodal stimulation over the left supraorbital; the cathode group received cathodal stimulation over the right dlPFC and anodal stimulation over the left supraorbital; and the sham group received sham tDCS. All subjects performed a computer-based stop-signal task before and after tDCS.
Performance on the response inhibition task after tDCS was improved in groups with both anodal and cathodal stimulation. Specifically, there was a decrease in the stop-signal reaction time in these subjects, whereas no difference was observed in the sham group. Consistent with signal detection theory, discrimination and decision bias was improved by anode tDCS relative to the sham group, while discrimination was also improved in the cathode group.
Anode and cathode tDCS of the right dlPFC improves response inhibition, with the right dlPFC may playing a key role in this process.
多项功能磁共振成像研究表明，背外侧前额叶皮质（dlPFC）是反应抑制的关键脑区。然而，其如何发挥这一功能仍不清楚。本研究调查经颅直流电刺激（tDCS）刺激右侧dlPFC是否会影响停止信号任务的表现。
共92名健康受试者参与本研究并随机分为三组。阳极组在右侧dlPFC接受阳极刺激，在左侧眶上接受阴极刺激；阴极组在右侧dlPFC接受阴极刺激，在左侧眶上接受阳极刺激；假刺激组接受假tDCS。所有受试者在tDCS前后均进行基于计算机的停止信号任务。
阳极和阴极刺激组在tDCS后的反应抑制任务表现均得到改善。具体而言，这些受试者的停止信号反应时间缩短，而假刺激组未观察到差异。与信号检测理论一致，相对于假刺激组，阳极tDCS改善了辨别和决策偏差，阴极组的辨别能力也得到了改善。
右侧dlPFC的阳极和阴极tDCS均可改善反应抑制，右侧dlPFC可能在此过程中起关键作用。
