Division of Functional and Restorative Neurosurgery and Division of Translational Neurosurgery, Department of Neurosurgery, Eberhard Karls University of Tübingen Tübingen, Germany ; Neuroprosthetics Research Group, Werner Reichardt Centre for Integrative Neuroscience, Eberhard Karls University of Tübingen Tübingen, Germany.
Department of Computer Engineering, Wilhelm-Schickard Institute for Computer Science, Eberhard Karls University of Tübingen Tübingen, Germany.
Front Hum Neurosci. 2014 May 6;8:285. doi: 10.3389/fnhum.2014.00285. eCollection 2014.
Prostheses for upper-limb amputees are currently controlled by either myoelectric or peripheral neural signals. Performance and dexterity of these devices is still limited, particularly when it comes to controlling hand function. Movement-related brain activity might serve as a complementary bio-signal for motor control of hand prosthesis.
We introduced a methodology to implant a cortical interface without direct exposure of the brain surface in an upper-limb amputee. This bi-directional interface enabled us to explore the cortical physiology following long-term transhumeral amputation. In addition, we investigated neurofeedback of electrocorticographic brain activity related to the patient's motor imagery to open his missing hand, i.e., phantom hand movement, for real-time control of a virtual hand prosthesis.
Both event-related brain activity and cortical stimulation revealed mutually overlapping cortical representations of the phantom hand. Phantom hand movements could be robustly classified and the patient required only three training sessions to gain reliable control of the virtual hand prosthesis in an online closed-loop paradigm that discriminated between hand opening and rest.
Epidural implants may constitute a powerful and safe alternative communication pathway between the brain and external devices for upper-limb amputees, thereby facilitating the integrated use of different signal sources for more intuitive and specific control of multi-functional devices in clinical use.
上肢截肢者目前使用肌电或周围神经信号来控制假肢。这些设备的性能和灵活性仍然有限，特别是在控制手部功能方面。与运动相关的大脑活动可以作为手部假肢运动控制的补充生物信号。
我们引入了一种方法，在上肢截肢者中无需直接暴露大脑表面即可植入皮质接口。这种双向接口使我们能够探索长期经肱骨干截肢后的皮质生理学。此外，我们研究了与患者运动想象相关的脑电活动的神经反馈，以打开他缺失的手，即幻手运动，实现对虚拟手假肢的实时控制。
事件相关脑活动和皮质刺激都揭示了幻手的相互重叠的皮质代表。幻手运动可以被稳健地分类，患者只需进行三次训练即可在在线闭环范式中获得对虚拟手假肢的可靠控制，该范式可以区分手的张开和休息。
硬膜内植入物可能构成上肢截肢者大脑与外部设备之间强大而安全的替代通讯途径，从而促进不同信号源的综合使用，以实现更直观和特定的多功能设备控制，这在临床应用中是非常重要的。
