Injecting instructions using intracortical microstimulation in association cortex

项目总结： 努力开发神经假体设备，为失明患者恢复功能， 听觉，或躯体感觉，通常旨在刺激神经系统的感觉通路 这种方式非常接近于它们的正常功能。然而，众所周知的聋人人工耳蜗植入物 即使受试者的大脑必须适应人工刺激，学会解读，也是成功的 声音和歧视性言论。仿生刺激感官通路是提供 神经系统的神经假体输入？ 在初步研究中，我们最近发现，受试者可以学习解释皮质内 微刺激(ICMS)通过运动前皮质(PM)的4个不同电极中的1个作为AS 执行4个任意关联动作中的1个的指令。即使PM中的ICMS不被认为是 唤起感官知觉，受试者学会在太低的电流和频率下使用PM-ICMS指令 唤起任何肌肉收缩或运动。此外，在将电极分配给运动后， 随机洗牌的受试者重新学习了这项任务，这表明低幅度的ICMS并没有简单地偏向 受试者表演特定的动作，而不是唤起受试者的感知或其他体验 能够辨别并学会将其解释为指令。 在这里，我们建议调查受试者是否能够体验、辨别和学习解释低- 额叶和顶叶其他选定区域通过不同单电极的波幅ICMS 只间接接受感觉信息的大脑皮质。在目标1中，我们将研究5个额区： 辅助运动区、额叶眼野、背外侧和腹外侧额叶皮质，以及 背侧前扣带回皮质。在目标2中，我们将检查5个顶区：5区，顶内内侧 顶区(顶前区)、外侧顶内区、前部顶内区和7a区。在AIM 3中 我们将确定受试者是否能够学习在这些额叶和顶叶区域解释ICMS，而不仅仅是 指示，但也可以作为反馈。这项工作的成果将扩大可用于 将人工输入实质上输送到神经系统。然后可能会开发出神经假体设备 使用这种输入来帮助受各种中枢和外周疾病影响的患者 神经系统包括视力丧失、感觉神经病、中风和多发性硬化症。

Project Summary: Efforts to develop neuroprosthetic devices that restore function for patients who have lost vision, hearing, or somatic sensation typically aim to stimulate the sensory pathways of the nervous system in a manner that mimics their normal function closely. Yet the well-known cochlear implant for deaf patients has been successful even though the subject’s brain must adapt to the artificial stimulation, learning to interpret sounds and discriminate speech. Is biomimetic stimulation of sensory pathways the only way to provide neuroprosthetic inputs to the nervous system? In preliminary studies, we recently found that subjects could learn to interpret intracortical microstimulation (ICMS) delivered through 1 of 4 different electrodes in the premotor cortex (PM) as instructions to perform 1 of 4 arbitrarily associated movements. Even though ICMS in PM is not thought to evoke sensory percepts, subjects learned to use PM-ICMS instructions at currents and frequencies too low to evoke any muscle contraction or movement. Moreover, after the assignment of electrodes to movements was shuffled randomly subjects relearned the task, indicating that low-amplitude ICMS did not simply bias the subjects to perform specific movements, but instead evoked percepts or other experiences that the subjects could distinguish and learned to interpret as instructions. Here we propose to investigate whether subjects can experience, distinguish and learn to interpret low- amplitude ICMS delivered through different single electrodes in other select areas of the frontal and parietal association cortex that receive sensory information only indirectly. In Aim 1 we will examine 5 frontal areas: the supplementary motor area, the frontal eye field, the dorsolateral and ventrolateral prefrontal cortex, and the dorsal anterior cingulate cortex. In Aim 2 we will examine 5 parietal areas: area 5, the medial intraparietal area (parietal reach region), the lateral intraparietal area, the anterior intraparietal area, and area 7a. In Aim 3 we will determine whether subjects can learn to interpret ICMS in these frontal and parietal areas not only as instructions, but alternatively as feedback. The results of this work will expand the territory available for delivering artificial inputs to the nervous system substantially. Neuroprosthetic devices then may be developed that use such inputs to help patients affected by a wide variety of diseases of the central and peripheral nervous system including visual loss, sensory neuronopathies, stroke, and multiple sclerosis.