Feasibility of a direct brain-to-muscle upper-limb neuroprosthesis

直接脑到肌肉上肢神经假体的可行性

• 批准号: 9108728
• 负责人: Dawn Marie Taylor
• 金额: --
• 依托单位: LOUIS STOKES CLEVELAND VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9108728
• 关键词: Activities of Daily Living; Animals; Atrophic; Brain; Brain Stem; Bypass; Cervical spinal cord injury; Contracts; Effectiveness; Electrodes; Encapsulated; Freedom; Hand; Implant; Individual; Injury; Joints; Juice; Knowledge; Learning; Left; Limb structure; Longevity; Methods; Microelectrodes; Modeling; Monkeys; Motion; Motor; Motor Cortex; Movement; Muscle; Musculoskeletal; Neck; Neurons; Paralysed; Pattern; Performance; Persons; Positioning Attribute; Process; Quality Control; Rewards; Signal Transduction; Spinal Cord; Spinal cord injury; System; Technology; Testing; Time; Training; Translating; Upper Extremity; Upper limb movement; Veterans; Well in self; analytical method; arm; arm function; arm movement; compare effectiveness; flexibility; improved; kinematics; limb movement; mind control; neuromuscular stimulation; neuroprosthesis; neurotransmission; novel; prevent; public health relevance; relating to nervous system; sensor; simulation

DESCRIPTION (provided by applicant): Implanted neuromuscular stimulation systems capable of restoring full arm and hand motion have now been implemented in people paralyzed below the neck due to spinal cord injury. Intracortical microelectrode arrays are also now being tested in other paralyzed individuals for chronically recording neural activity in the motor cortex. By combining these two technologies, we can potentially develop complete systems that will bypass damage in the spinal cord and restore natural movement by thought to people with spinal cord injuries. However, if the brain signals are decoded into kinematic aspects of movements (e.g. limb position, velocity, joint angles etc.), then we still have to develop additional technology to convert those kinematic commands into the muscle stimulation patterns needed to generate the desired movement. This is not a trivial task. In this study, we will evaluate the alternative approach of retraining the bain to control the muscle stimulators directly, therefore bypassing the challenging and still open problem of how best to translate one's intended movement into the muscle activation levels that will generate those movements. Several studies have shown that local field potentials and the firing rates of motor cortical neurons correlate with recorded muscle activity in able- bodied animals. However, in this study we are specifically testing if motor cortex can be retrained to command the muscle activation levels needed to generate the desired motion of a paralyzed limb where only a subset of the normal muscles can be stimulated and muscles have atrophied after paralysis. Since intracortical recording electrodes are not always capable of detecting firin of individual neurons as the body encapsulates the electrodes over time, we will also compare the effectiveness of using firing rates of the recorded neurons to control the muscle stimulators versus using the more robustly recorded local field potentials to control muscle stimulators. The novel decoding methods we will use in this study can be applied clinically to paralyzed individuals and not just able-bodied animals. In aims 1-2, monkeys will be trained to use the firing rates of ensembles of motor and premotor cortical neurons to control the activation levels of subsets of muscles in a real-time musculoskeletal simulation of a paralyzed arm. The monkeys will be given juice rewards when they successfully move the simulated arm to different targets. In aim1 the monkeys will control movements of the model arm in the horizontal plane by controlling the activation levels of six muscles. In aim 2 external forces will be applied to the model arm. The animals will have to alter the muscle activation levels (by alternating their neural firing) in order to still get the arm to the targets. Aim 3 will determine if the same level of arm control seen in aims 1 & 2 can also be achieved using only local field potentials recorded from intracortical microelectrode arrays.

描述（由申请人提供）： 能够恢复手臂和手部完整运动的植入式神经肌肉刺激系统现已应用于因脊髓损伤而导致颈部以下瘫痪的患者。目前还在其他瘫痪个体中测试皮质内微电极阵列，以长期记录运动皮层的神经活动。通过结合这两种技术，我们有可能开发出完整的系统，绕过脊髓损伤并恢复脊髓损伤患者的自然运动。然而，如果大脑信号被解码为运动的运动学方面（例如肢体位置、速度、关节角度等），那么我们仍然需要开发额外的技术来将这些运动学命令转换为产生所需运动所需的肌肉刺激模式。这不是一项简单的任务。在这项研究中，我们将评估重新训练贝恩以直接控制肌肉刺激器的替代方法，从而绕过如何最好地将一个人的预期运动转化为将产生这些运动的肌肉激活水平的具有挑战性且仍然悬而未决的问题。多项研究表明，运动皮质神经元的局部场电位和放电率与记录的健全动物的肌肉活动相关。然而，在这项研究中，我们专门测试运动皮层是否可以重新训练，以控制产生瘫痪肢体所需运动所需的肌肉激活水平，在瘫痪肢体中，只能刺激一部分正常肌肉，并且瘫痪后肌肉萎缩。由于皮质内记录电极并不总是能够检测单个神经元的 firin，因为随着时间的推移，身体会封装电极，因此我们还将比较使用记录神经元的放电率来控制肌肉刺激器与使用更稳健记录的局部场的有效性控制肌肉刺激器的潜力。我们将在本研究中使用的新颖解码方法可以在临床上应用于瘫痪个体，而不仅仅是身体健全的动物。在目标 1-2 中，猴子将被训练使用运动和前运动皮层神经元群的放电率来控制瘫痪手臂的实时肌肉骨骼模拟中肌肉子集的激活水平。当猴子成功地将模拟手臂移动到不同的目标时，将获得果汁奖励。在 Target1 中，猴子将通过控制六块肌肉的激活水平来控制模型手臂在水平面上的运动。在目标 2 中，外力将施加到模型手臂上。动物必须改变肌肉激活水平（通过改变它们的神经 射击）以便仍然使手臂到达目标。目标3将判断手臂是否处于同一水平 目标 1 和 2 中的控制也可以仅使用皮质内微电极阵列记录的局部场电位来实现。