Ding Li, Sun Qiang, Jiang Ning, He Jiayuan, Jia Jie
Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China.
The National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, China.
Front Neurosci. 2023 Mar 20;17:1138406. doi: 10.3389/fnins.2023.1138406. eCollection 2023.
The therapeutic efficacy of mirror visual feedback (MVF) is attributed to the perception of embodiment. This study intends to investigate the instantaneous effect of embodiment on brain connectivity. Twelve healthy subjects were required to clench and open their non-dominant hands and keep the dominant hands still during two experimental sessions. In the first session, the dominant hand was covered and no MVF was applied, named the sham-MVF condition. Random vibrotactile stimulations were applied to the non-dominant hand with MVF in the subsequent session. Subjects were asked to pedal while having embodiment perception during motor tasks. As suggested by previous findings, trials of no vibration and continuous vibration were selected for this study, named the condition of MVF and vt-MVF. EEG signals were recorded and the alterations in brain connectivity were analyzed. The average node degrees of sham-MVF, MVF, and vt-MVF conditions were largely different in the alpha band (9.94, 11.19, and 17.37, respectively). Further analyses showed the MVF and vt-MVF had more nodes with a significantly large degree, which mainly occurred in the central and the visual stream involved regions. Results of network metrics showed a significant increment of local and global efficiency, and a reduction of characteristic path length for the vt-MVF condition in the alpha and beta bands compared to sham-MVF, and in the alpha band compared to MVF. Similar trends were found for MVF condition in the beta band compared to sham-MVF. Moreover, significant leftward asymmetry of global efficiency and rightward asymmetry of characteristic path length was reported in the vt-MVF condition in the beta band. These results indicated a positive impact of embodiment on network connectivity and neural communication efficiency, which reflected the potential mechanisms of MVF for new insight into neural modulation.
镜像视觉反馈（MVF）的治疗效果归因于具身认知。本研究旨在探究具身认知对大脑连通性的即时影响。在两个实验环节中，12名健康受试者被要求握紧和张开其非优势手，并保持优势手静止。在第一个环节中，优势手被遮盖且未应用MVF，称为假MVF条件。在随后的环节中，对非优势手施加随机振动触觉刺激并伴有MVF。要求受试者在运动任务中产生具身认知时进行踩踏板动作。根据先前的研究结果，本研究选择了无振动和持续振动的试验，分别称为MVF条件和vt-MVF条件。记录脑电图信号并分析大脑连通性的变化。在α波段，假MVF、MVF和vt-MVF条件的平均节点度差异很大（分别为9.94、11.19和17.37）。进一步分析表明，MVF和vt-MVF有更多节点具有显著较大的度，主要出现在中央和视觉流相关区域。网络指标结果显示，与假MVF相比，vt-MVF条件在α和β波段的局部和全局效率显著增加，特征路径长度减少；与MVF相比，在α波段也有类似情况。与假MVF相比，MVF条件在β波段也有类似趋势。此外，在β波段的vt-MVF条件下，报告了全局效率的显著左向不对称和特征路径长度的右向不对称。这些结果表明具身认知对网络连通性和神经通信效率有积极影响，这反映了MVF在神经调制方面新见解的潜在机制。
