Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
IEEE Trans Neural Syst Rehabil Eng. 2012 Jul;20(4):595-604. doi: 10.1109/TNSRE.2012.2194309. Epub 2012 Apr 25.
This paper proposes the development and experimental tests of a self-paced asynchronous brain-computer interfacing (BCI) system that detects movement related cortical potentials (MRCPs) produced during motor imagination of ankle dorsiflexion and triggers peripheral electrical stimulations timed with the occurrence of MRCPs to induce corticospinal plasticity. MRCPs were detected online from EEG signals in eight healthy subjects with a true positive rate (TPR) of 67.15 ± 7.87% and false positive rate (FPR) of 22.05 ±9.07%. The excitability of the cortical projection to the target muscle (tibialis anterior) was assessed before and after the intervention through motor evoked potentials (MEP) using transcranial magnetic stimulation (TMS). The peak of the evoked potential significantly (P=0.02) increased after the BCI intervention by 53 ± 43% (relative to preintervention measure), although the spinal excitability (tested by stretch reflexes) did not change. These results demonstrate for the first time that it is possible to alter the corticospinal projections to the tibialis anterior muscle by using an asynchronous BCI system based on online motor imagination that triggered peripheral stimulation. This type of repetitive proprioceptive feedback training based on self-generated brain signal decoding may be a requirement for purposeful skill acquisition in intact humans and in the rehabilitation of persons with brain damage.
本文提出了一种自定步长的异步脑机接口 (BCI) 系统的开发和实验测试，该系统可检测到在踝关节背屈运动想象过程中产生的运动相关皮层电位 (MRCP)，并根据 MRCP 的发生触发与外周电刺激，以诱导皮质脊髓可塑性。在八名健康受试者的 EEG 信号中在线检测到了 MRCP，真阳性率 (TPR) 为 67.15±7.87%，假阳性率 (FPR) 为 22.05±9.07%。通过经颅磁刺激 (TMS) 使用运动诱发电位 (MEP) 在干预前后评估皮质投射到目标肌肉 (胫骨前肌) 的兴奋性。诱发电位的峰值在 BCI 干预后显著（P=0.02）增加了 53±43%（相对于干预前的测量值），尽管脊髓兴奋性（通过牵张反射测试）没有变化。这些结果首次证明，通过使用基于在线运动想象的异步 BCI 系统触发外周刺激，有可能改变皮质脊髓对胫骨前肌的投射。这种基于自我产生的脑信号解码的重复本体感受反馈训练可能是完整人类获得有目的技能和脑损伤患者康复的要求。
