DEVELOPMENT OF THE NEXT GENERATION OF ARTIFICIAL LIMB SYSTEMS WHICH WILL ALLOW VOLUNTARY MOVEMENT AND BE CAPABLE OF PROVIDING PATIENTS WITH A HIGH DEGREE OF SOMATIC SENSATION

感觉功能我们首先明确了微电刺激（在神经内输入到单个慢适应（SA）机械感受器单元）与唤醒的压力感觉的强度和区域之间的定性和定量关系。采用方波脉冲钨微电极进行电微刺激，发现诱发感觉的主观强度似乎与频率的正幂有关；然而，电刺激的振幅基本上没有变化。接下来，我们开发了一个人工手臂系统的原型，该系统能够感知机械刺激，然后使用相同的技术将这些刺激作为相应的躯体感觉传递并显示给受试者，结果如上所述。采用机械手系统作为人工系统；它的手指上覆盖着一层传导压力的橡胶。然后将更多的re应用于压力传导橡胶；微型计算机利用导压橡胶的输出电压来确定刺激感觉神经纤维的电脉冲频率，然后将这些电脉冲通过钨微电极输出到感觉神经纤维，从而在投射区域引起压力感觉。该系统的工作方式令人满意，受试者可以感受到由施加在机械手的压力传导橡胶上的压力产生的压力感。运动功能我们尝试通过钨微电极直接用电脉冲刺激运动神经纤维来控制手和手指的运动。然而，只有两种情况下，vie可以记录运动神经信号，并通过电刺激运动神经纤维来移动相关肌肉。我们目前正在研究提高记录信号信噪比的方法。少

SENSORY FUNCTIONSWe firstly clarified the qualitative and quantitative relationship between the microelectrostimulation (which is input intraneurally into a single slowly-adapting (SA) mechanoreceptor unit) and the intensities and areas of the evoked pressure sensations using awake human volunteers. Electrical microstimulation performed with tungsten microelectrode using square-wave pulses revealed that the subjective magnitude of the evoked sensation was appeared to be related to a positive power of the frequency ; however, there was essentially no change in the amplitude of the electrical stimulation. Next, we developed a prototype of an artificial arm system capable of sensing mechanical stimuli and then transferring and displaying these stimuli to the subject as the corresponding somatic sensations using the same technique and the results as stated above. A robot hand system was used as an artificial system ; its finger was covered with a sheet of pressure-conductive rubber. Pressu … More re was then applied to the pressure-conductive rubber ; a microcomputer used the output voltage of the pressure-conductive rubber to determine the frequency of the electrical pulses for stimulating the sensory nerve fiber, and these electrical pulses were then output to the sensory nerve fiber via the tungsten microelectrode so that the pressure sensation was evoked at the projected area. The system worked in a satisfactory manner, and the subjects could feel the pressure sensation resulting from the pressure that was applied to the pressure conductive-rubber of the robot hand.MOTOR FUNCTIONSWe attempted to control the movement of the hand and fingers by the stimulating motor nerve fibers directly with electrical pulses via the tungsten microelectrode. However, there were only two cases in which vie could record motor nerve signals and move the concerned muscle by electrically stimulating the motor nerve fiber.We are currently investigating methods for improving the S/N ratio of the recorded signals. Less