Intra vs. extracortical command signals to restore six dimensional hand movements

描述（由申请人提供）：该项目的长期目标是恢复手臂和手的功能，颈部以下瘫痪的人由于脊髓损伤。新的植入式神经修复装置现在可以通过电激活周围神经来恢复瘫痪患者的手臂和手部运动。安装在轮椅上的机器人手臂也可以为严重瘫痪的人提供接触和抓握能力。然而，这些技术的一个当前限制是用户必须能够向设备传达他们希望他们的手臂和手如何移动。在颈部以下瘫痪的人中，任何辅助设备的控制选项都限于使用颈部以上的保留功能。许多命令选项，例如语音命令、舌头触摸按钮或下巴操作的按钮，可能是笨拙的，并且可能干扰说话、进食和正常的社交互动。直接来自大脑的非预期肢体运动将使这些人仅通过思考来移动他们的手臂和手，同时也使他们能够保持正常使用他们的脸和嘴。两种主要类型的植入式大脑记录技术正在被开发和商业化用于长期人类用途：1）小的皮质内微电极，其被植入大脑中几毫米并且可以检测许多单个神经元的放电活动，以及2）较大的皮质外电极，其检测来自大脑外部位置的较大神经元组的平均电活动。这两种类型的记录技术都显示出作为生成用于控制辅助设备的运动命令的手段的前景。皮质内微电极已被用于猴子和人类，以直接控制计算机光标和机械臂的二维和三维运动。大脑皮层外记录也被用于人类控制计算机光标和机器人的二维运动。目前的研究将使用一个猴子模型，其中每只动物都接受了两种类型的大脑记录技术，其配置类似于未来五年内可能用于瘫痪人类的配置。然后，将开发方法来将来自每种类型的大脑记录技术的信号转换为使用当前上肢神经假体系统所需的特定运动指令（即，将手放在空间中的何处，手打开/闭合的程度，前臂的旋前/旋后角度以及手腕屈曲/伸展角度）。将测量每种类型的大脑记录技术产生的运动命令的速度、准确性和稳定性。通过开发使用两种大脑记录技术来生成控制上肢神经假体所需的运动命令的方法，这项研究将把两种大脑记录技术向前推进到实际应用中，同时为潜在用户提供他们需要的性能信息，以权衡这些好处与固有风险，并决定这些植入的大脑记录系统是否适合他们。公共卫生相关性：现在可以使用植入式设备激活瘫痪患者的肌肉，以恢复手臂和手部运动。这个项目的目标是让这些瘫痪的人能够通过思考来控制自己手臂和手的运动。这项研究开发了使用两种不同类型的传感器从大脑中检测一个人想要的运动的方法，然后为潜在用户提供他们需要的信息，以决定哪种类型的传感器适合他们。

DESCRIPTION (provided by applicant): The long-term goal of this project is to restore arm and hand function to people paralyzed below the neck due to a spinal cord injury. New implanted neuroprosthetic devices can now restore arm and hand movements to paralyzed individuals by electrically activating the peripheral nerves. Wheelchair-mounted robotic arms can also provide reach and grasp capabilities to the severely paralyzed. However, one current limitation of these technologies is that the user must be able to convey to the device how they want their arm and hand to move. In people paralyzed below the neck, control options for any assistive device are limited to using retained function from the neck up. Many command options, such as voice commands, tongue-touch keypads, or chin- operated joysticks, can be awkward and can interfere with talking, eating, and normal social interaction. Accessing desired limb movements directly from the brain would allow these people to move their arm and hand just by thinking about doing so while also allowing them to retain normal use of their face and mouth. Two main types of implanted brain recording technologies are being developed and commercialized for chronic human use: 1) small intracortical microelectrodes that are implanted a few millimeters into the brain and can detect the firing activity of many individual neurons, and 2) larger extracortical electrodes that detect the average electrical activity of larger groups of neurons from locations outside the brain. Both types of recording technologies have shown promise as a means to generate movement commands for controlling assistive devices. Intracortical microelectrodes have been used in monkeys and humans to directly control two- and three-dimensional movements of computer cursors and robotic arms. Extracortical brain recordings have also been used in humans to control the two-dimensional movements of computer cursors and robots. The present study will use a monkey model in which each animal receives both types of brain recording technologies in configurations similar to those likely to be commercially available to paralyzed humans within the next five years. Methods will then be developed to translate signals from each type of brain recording technology into the specific movement instructions needed to use the current upper-limb neuroprosthesis systems (i.e. where to place the hand in space, how much to open/close the hand, pronation/supination angle of the forearm, and wrist flexion/extension angle). The speed, accuracy, and stability of the movement commands generated with each type of brain recording technology will be measured. By developing methods for using both brain recording technologies to generate the movement commands needed to control an upper limb neuroprosthesis, this study will move both brain recording technologies forward into practical applications while providing potential users with the performance information they need to weigh these benefits against the inherent risks and decide if either of these implanted brain recording systems is right for them. PUBLIC HEALTH RELEVANCE: Implanted devices are now available that can activate muscles of paralyzed individuals to restore arm and hand movements. The goal of this project is to enable these paralyzed individuals to control the movements of their own arm and hand just by thinking about doing so. This study develops methods for detecting a person's desired movement from the brain using two different types of sensors and then provides potential users with the information they need to decide which type of sensor is right for them.