International Paraplegic Foundation Chair in Spinal Cord Repair, Center for Neuroprosthetics and Brain Mind Institute, Swiss Federal Institute of Technology (EPFL), Lausanne CH-1015, Switzerland.
Translational Neural Engineering Lab, Center for Neuroprosthetics and Institute of Bioengineering, School of Bioengineering, Swiss Federal Institute of Technology (EPFL), Lausanne CH-1015, Switzerland. Automatic Control Laboratory, Swiss Federal Institute of Technology (ETHZ), Zurich CH-8092, Switzerland.
Sci Transl Med. 2014 Sep 24;6(255):255ra133. doi: 10.1126/scitranslmed.3008325.
Neuromodulation of spinal sensorimotor circuits improves motor control in animal models and humans with spinal cord injury. With common neuromodulation devices, electrical stimulation parameters are tuned manually and remain constant during movement. We developed a mechanistic framework to optimize neuromodulation in real time to achieve high-fidelity control of leg kinematics during locomotion in rats. We first uncovered relationships between neuromodulation parameters and recruitment of distinct sensorimotor circuits, resulting in predictive adjustments of leg kinematics. Second, we established a technological platform with embedded control policies that integrated robust movement feedback and feed-forward control loops in real time. These developments allowed us to conceive a neuroprosthetic system that controlled a broad range of foot trajectories during continuous locomotion in paralyzed rats. Animals with complete spinal cord injury performed more than 1000 successive steps without failure, and were able to climb staircases of various heights and lengths with precision and fluidity. Beyond therapeutic potential, these findings provide a conceptual and technical framework to personalize neuromodulation treatments for other neurological disorders.
脊髓感觉运动回路的神经调节可改善动物模型和脊髓损伤患者的运动控制。在使用常见的神经调节设备时，电刺激参数是手动调节的，并且在运动过程中保持不变。我们开发了一种机械框架，以实时优化神经调节，从而实现大鼠运动过程中腿部运动学的高保真控制。我们首先揭示了神经调节参数与不同感觉运动回路募集之间的关系，从而对腿部运动学进行了预测性调整。其次，我们建立了一个具有嵌入式控制策略的技术平台，该平台实时集成了强大的运动反馈和前馈控制回路。这些进展使我们能够构思一种神经假体系统，该系统可在瘫痪大鼠的连续运动中控制广泛的足部轨迹。完全性脊髓损伤的动物能够连续完成 1000 多步而不失败，并且能够精确和流畅地攀爬各种高度和长度的楼梯。除了治疗潜力之外，这些发现还为其他神经障碍的神经调节治疗提供了个性化的概念和技术框架。
