Li Min, Chen Jing, He Bo, He Guoying, Zhao Chen-Guang, Yuan Hua, Xie Jun, Xu Guanghua, Li Jichun
School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
Department of Rehabilitation, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Front Neurosci. 2023 May 23;17:1149265. doi: 10.3389/fnins.2023.1149265. eCollection 2023.
Providing stimulation enhancements to existing hand rehabilitation training methods may help stroke survivors achieve better treatment outcomes. This paper presents a comparison study to explore the stimulation enhancement effects of the combination of exoskeleton-assisted hand rehabilitation and fingertip haptic stimulation by analyzing behavioral data and event-related potentials.
The stimulation effects of the touch sensations created by a water bottle and that created by cutaneous fingertip stimulation with pneumatic actuators are also investigated. Fingertip haptic stimulation was combined with exoskeleton-assisted hand rehabilitation while the haptic stimulation was synchronized with the motion of our hand exoskeleton. In the experiments, three experimental modes, including exoskeleton-assisted grasping motion without haptic stimulation (Mode 1), exoskeleton-assisted grasping motion with haptic stimulation (Mode 2), and exoskeleton-assisted grasping motion with a water bottle (Mode 3), were compared.
The behavioral analysis results showed that the change of experimental modes had no significant effect on the recognition accuracy of stimulation levels ( = 0.658), while regarding the response time, exoskeleton-assisted grasping motion with haptic stimulation was the same as grasping a water bottle ( = 0.441) but significantly different from that without haptic stimulation ( = 0.006). The analysis of event-related potentials showed that the primary motor cortex, premotor cortex, and primary somatosensory areas of the brain were more activated when both the hand motion assistance and fingertip haptic feedback were provided using our proposed method (P300 amplitude 9.46 μV). Compared to only applying exoskeleton-assisted hand motion, the P300 amplitude was significantly improved by providing both exoskeleton-assisted hand motion and fingertip haptic stimulation ( = 0.006), but no significant differences were found between any other two modes (Mode 2 vs. Mode 3: = 0.227, Mode 1 vs. Mode 3: = 0.918). Different modes did not significantly affect the P300 latency ( = 0.102). Stimulation intensity had no effect on the P300 amplitude ( = 0.295, 0.414, 0.867) and latency ( = 0.417, 0.197, 0.607).
Thus, we conclude that combining exoskeleton-assisted hand motion and fingertip haptic stimulation provided stronger stimulation on the motor cortex and somatosensory cortex of the brain simultaneously; the stimulation effects of the touch sensations created by a water bottle and that created by cutaneous fingertip stimulation with pneumatic actuators are similar.
为现有的手部康复训练方法提供刺激增强措施可能有助于中风幸存者取得更好的治疗效果。本文通过分析行为数据和事件相关电位，进行了一项对比研究，以探究外骨骼辅助手部康复与指尖触觉刺激相结合的刺激增强效果。
还研究了水瓶产生的触觉以及气动致动器进行的指尖皮肤刺激产生的触觉的刺激效果。指尖触觉刺激与外骨骼辅助手部康复相结合，同时触觉刺激与手部外骨骼的运动同步。在实验中，比较了三种实验模式，包括无触觉刺激的外骨骼辅助抓握运动（模式1）、有触觉刺激的外骨骼辅助抓握运动（模式2）和拿着水瓶的外骨骼辅助抓握运动（模式3）。
行为分析结果表明，实验模式的变化对刺激水平的识别准确率没有显著影响（=0.658），而在反应时间方面，有触觉刺激的外骨骼辅助抓握运动与拿着水瓶的抓握运动相同（=0.441），但与无触觉刺激的抓握运动有显著差异（=0.006）。事件相关电位分析表明，当使用我们提出的方法同时提供手部运动辅助和指尖触觉反馈时，大脑的初级运动皮层、运动前皮层和初级体感区域的激活程度更高（P300波幅为9.46μV）。与仅应用外骨骼辅助手部运动相比，同时提供外骨骼辅助手部运动和指尖触觉刺激可显著提高P300波幅（=0.006），但其他任意两种模式之间均未发现显著差异（模式2与模式3：=0.227，模式1与模式3：=0.918）。不同模式对P300潜伏期没有显著影响（=0.102）。刺激强度对P300波幅（=0.295、0.414、0.867）和潜伏期（=0.417、0.197、0.607）均无影响。
因此，我们得出结论：外骨骼辅助手部运动与指尖触觉刺激相结合可同时对大脑的运动皮层和体感皮层提供更强的刺激；水瓶产生的触觉与气动致动器进行的指尖皮肤刺激产生的触觉的刺激效果相似。
