CRCNS: Extracting Dynamical Structure Embedded in Motor Preparatory Activity

CRCNS：提取运动准备活动中嵌入的动态结构

• 批准号: 7488914
• 负责人: Krishna V Shenoy
• 金额: $ 34.23万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7488914
• 关键词: Accounting; Algorithms; Amputation; Amyotrophic Lateral Sclerosis; Area; Basic Science; Behavior; Biological Models; Biological Neural Networks; Brain; Cells; Chronic; Cognitive; Communication; Count; Cues; Data; Degenerative Disorder; Development; Drops; Electrodes; Exhibits; Experimental Models; Figs - dietary; Fire - disasters; Goals; Implant; Individual; Laboratories; Learning; Left; Location; Measures; Methods; Modeling; Monkeys; Motor; Movement; Nature; Neurons; Non-linear Models; Operative Surgical Procedures; Output; Patients; Performance; Population; Positioning Attribute; Preparation; Principal Investigator; Process; Prosthesis; Quality of life; Range; Rate; Recurrence; Research; Research Personnel; Speed; Spinal cord injury; Standards of Weights and Measures; Structure; System; Techniques; Technology; Testing; Time; Upper arm; Variant; Work; base; design; desire; improved; insight; interest; neural circuit; neural prosthesis; neuromechanism; neurophysiology; programs; relating to nervous system; research study; two-dimensional; vector

DESCRIPTION (provided by applicant): Spiking activity from neurophysiological experiments often exhibits dynamics beyond that driven by external stimulation, presumably reflecting the extensive recurrence of neural circuitry. Characterizing these dynamics may reveal important features of neural computation, particularly during internally-driven "cognitive" operations. For example, neurons in premotor cortex (PMd) are active during a "planning" period separating movement-target specification and a movement-initiation cue. Recent evidence suggests that PMd neural activity settles to a movement-specific state during this period. Can trial-to-trial variation in behavior be predicted from the dynamics of settling? Current methods to characterize recurrent neural dynamics on a trial-by-trial basis, and thus answer this and related questions, are limited. Standard methods average activity from different trials or different cells, and so cannot express variable dynamics. The proposed research will test the hypothesis that the dynamics underlying PMd plan activity can be described by a low-dimensional hidden non-linear dynamical systems (HNLDS) model, with underlying recurrent structure and stochastic point-process output. Such a model is capable of expressing rich dynamics, but the task of learning the model parameters from spike data is challenging. The proposed research will develop and validate algorithms for parameter estimation, and then characterize the dynamics in PMd data recorded from an electrode array while monkeys perform delayed-reach tasks. Single trial estimates of underlying dynamics can then be used to predict variation in details of reaching motor behavior. The proposed research program will directly inform cortically-controlled neural prosthesis research in our laboratory and elsewhere. Such motor and communication prostheses could dramatically improve the quality of life for patients with upper spinal cord injuries, amputations, ALS and other neuro-degenerative diseases. The proposed research program will increase our understanding of how PMd rapidly prepares movements, and thereby help increase the speed and accuracy of prosthetic systems.

描述（由申请人提供）： 来自神经生理实验的尖峰活性通常表现出由外部刺激驱动的动力学，大概反映了神经回路的广泛复发。表征这些动力学可能会揭示神经计算的重要特征，尤其是在内部驱动的“认知”操作中。例如，在“计划”期间，将运动目标规范和运动发射提示分开的“计划”期间，前运动皮层（PMD）中的神经元处于活动状态。最近的证据表明，在此期间，PMD神经活动定居在特定于运动的状态下。可以通过沉降的动态来预测行为的试验变化？当前通过试用的反复神经动力学表征并回答相关问题的方法是有限的。标准方法来自不同试验或不同细胞的平均活性，因此无法表达可变动力学。拟议的研究将检验以下假设：PMD计划活动的基本动力学可以通过低维隐藏的非线性动力学系统（HNLDS）模型来描述，并具有基本的复发结构和随机的点过程输出。这样的模型能够表达丰富的动态，但是从Spike数据中学习模型参数的任务具有挑战性。拟议的研究将开发和验证参数估计的算法，然后表征从电极阵列记录的PMD数据中的动力学，而猴子执行延迟的范围任务。然后，可以使用基本动力学的单个试验估计来预测达到运动行为的细节的变化。 拟议的研究计划将直接在我们的实验室和其他地方直接为皮质控制的神经假体研究提供信息。这种运动和沟通假体可以大大改善上脊髓损伤，截肢，ALS和其他神经脱生疾病的患者的生活质量。拟议的研究计划将提高我们对PMD如何快速准备运动的理解，从而有助于提高假肢系统的速度和准确性。