Journal of Psychological Science ›› 2024, Vol. 47 ›› Issue (4): 812-818.DOI: 10.16719/j.cnki.1671-6981.20240406

• General Psychology, Experimental Psychology & Ergonomics • Previous Articles     Next Articles

Lateralization of Brain Function in Task Switching: Evidence Based on tDCS and TMS Technology

Wang Xuan1,2, Zhu Rongjuan1,2, You Xuqun1,2   

  1. 1School of Psychology, Shaanxi Normal University, Xi'an, 710062;
    2Key Laboratory for Behavior and Cognitive Neuroscience of Shaanxi Province, Xi'an, 710062
  • Online:2024-07-20 Published:2024-07-17

任务转换的脑功能偏侧化效应:基于tDCS和TMS技术的研究*

王煊1,2, 朱荣娟1,2, 游旭群**1,2   

  1. 1陕西师范大学心理学院,西安,710062;
    2陕西省行为与认知神经科学重点实验室,西安,710062
  • 通讯作者: ** 游旭群, E-mail: youxuqun@snnu.edu.cn
  • 基金资助:
    *本研究得到中央高校基本科研业务费专项资金(2021TS099)的资助

Abstract: Task switching is one component of executive function. It refers to the process of switching from one cognitive task to another, emphasizing the ability to flexibly switch between tasks, goals or psychological settings. Because task switching is the most basic daily cognitive activity of human beings, it is of great importance to study its neural mechanisms. In the research on the neural mechanism of task switching, researchers have made some research achievements in the two research fields by using transcranial direct current stimulation (tDCS) to explore the lateralization effects of the two hemispheres of the brain.
Firstly, researchers concluded that the frontal lobe is the core brain area of task switching, in which the left hemisphere plays an important role. The main method is to change the tDCS montage. For example, to separate the contribution of left and right DLPFC, researchers put anode in the left DLPFC and cathode in the right OFC for a group, and in the other group, cathode was put in the left DLPFC and anode was put in the right OFC. All participants received tDCS for 15 minutes at 1 mA intensity and the results showed that the left DLPFC receiving anode stimulation could improve the ability of task switching. However, not all experiments obtained similar results. For example, some studies used the elderly as the participants and took the cue paradigm as the switching task. All participants received tDCS for 30 minutes at 1 mA intensity each day with 10 consecutive days. However, it was found that the individual switching cost did not decrease and the performance of task switching did not improve. Therefore, it could not be proved that the left hemisphere of DLPFC is the dominant hemisphere of task switching. It was speculated that the reason for the controversy in these studies may be that tDCS is only an auxiliary tool for cognitive training rather than an independent cognitive regulation tool. As a result, in some studies, the advantages of left DLPFC in task switching cannot be highlighted. In addition, even if the anode tDCS on left DLPFC may improve the performance of task switching independently of training. However, some variables weaken the effect of tDCS, such as aging factors.
Secondly, the left and right hemispheres of the frontal region cooperate to form neural loop movement to support task switching. By changing the tDCS montage, researchers found that the endogenous preparation in the process of task switching needs the main force of the right DLPFC to participate in and inhibit the inappropriate task setting. Meanwhile, the exogenous regulation relies on the left DLPFC to perform a top-down adaptation process. In addition, different task types will affect the neural circuit movement in the right and left hemispheres.
Future studies should be improved in five aspects. First of all, it is of significant to improve the application level of tDCS technology. For example, researchers should pay attention to the effectiveness of tDCS stimulation, experimental ethics and individual differences. Moreover, in addition to the frontal lobe, it is necessary to study other brain regions, such as the parietal lobe. Moreover, other neural regulation technologies such as Transcranial Magnetic Simulation (TMS for short) and biofeedback could be used in future studies, and future studies with functional magnetic resonance (fMRI) combined with online tDCS should be performed to test the asymmetric involvement of right and left hemispheres in task switching. Besides, researchers should explore the mystery of brain function lateralization in task switching from the perspectives of physiological anatomy, molecular genetics, psychiatry, and other disciplines. Last but not least, future studies should take deductive reasoning and inductive reasoning as the guiding ideology.

Key words: task switching, lateralization of brain function, tDCS, TMS

摘要: 任务转换是执行功能的重要成分之一,指从一个认知任务转换到另一个认知任务的过程。在对任务转换的脑机制研究中,脑功能的偏侧化效应是一项重要内容,近年来,研究者通过经颅直流电刺激和经颅磁刺激等技术对DLPFC脑区、IFJ脑区等脑区的偏侧化效应进行了研究。虽然研究尚处于起步阶段,且存在一定争议,但得到较一致的结论是:第一,这些脑区的左侧优势较突出,在任务转换过程中发挥自上而下的适应性调节等核心功能;第二,在左侧功能优势的基础上,这些脑区的右侧也发挥抑制控制等功能,两侧形成高效的分工合作,形成生理性平衡。目前,部分研究结果已经应用于针对抑郁症患者和脑卒中患者等特殊人群的认知功能障碍治疗中。未来应进一步提高对tDCS和TMS技术的运用水平,逐渐从传统技术向高精度技术跨越,并引入其他神经调控方法,结合脑成像技术开展实证研究。在此基础上,注重对差异性结果的分析和解释,实现对任务转换脑功能偏侧化理论的拓展与整合。

关键词: 任务转换, 脑功能偏侧化, 经颅直流电刺激, 经颅磁刺激