CAREER: Probing the Neural Integration of Sensorimotor Signals for Limb Motor Coordination and Perception

PI：乔伊纳，威尔萨恩提案号：1553895人脑发出命令产生运动。然而，由于中枢神经系统内在的沟通和处理延迟，仅仅依靠运动产生的感觉不足以快速调整和更新未来的运动计划。有强有力的行为证据表明，为了确保充分的控制，大脑使用有关发出的运动命令的信息来形成对身体运动产生的预期感觉的预测。尽管有这些证据，但大脑如何将这些感觉反馈预测与实际的运动诱导感觉结合起来，以实现运动控制和自我运动感知，在很大程度上仍然是未知的。通过学生的参与和拓展活动，这个职业建议为长期的研究和教育生涯奠定了基础，以解决这些知识上的差距。利用多种技术，研究者将系统地检查实际和预测的感觉反馈对上肢行为的贡献。附带放电（CD，也称为参考拷贝）是在产生电机信号的同时对电机命令进行的内部复制。这个信号被用来预测身体的未来状态和由于运动而产生的预期感官后果。这种内部状态信息与延迟感官信号的整合对于精确的运动控制和运动感知至关重要。然而，人们对这种信号在人类中的特性知之甚少，也不知道这种内部运动信息是如何与传入感觉反馈相结合的。尽管对内部状态估计了解甚少，但它仍然是肢体运动和前馈控制计算模型的一个关键特征。为了直接解决目前的知识空白，拟议的研究旨在(1)量化本体感觉和内部肢体状态估计的准确性和敏感性，(2)计算描述这些信号如何组合以帮助感知和运动协调，以及(3)通过应用经颅磁刺激顶叶皮层和小脑区域确定行为与这些信号的神经处理之间的因果关系。为了实现项目目标，将利用不同的技术（计算建模、非侵入性神经刺激和定量行为分析）来推进感觉运动整合和控制的计算框架。增加对这种神经整合的理解可能(1)为理解实际和预测的感觉信息如何促进复杂行为（例如，眼手和双手协调）提供基础；(2)有助于定义有效的神经假体和大脑所需的不同感觉信息的约束（例如，时间和灵敏度）。机器接口控制和(3)有助于区分几种神经疾病中前馈运动控制缺陷的基础。重要的是，该项目促进了来自不同背景的学生，特别是少数民族学生的包容和培训，并鼓励向社区内广泛的参与者（从小学生到退休人员）推广和传播科学研究。

PI: Joiner, Wilsaan Proposal Number: 1553895The human brain issues commands to produce movement. However, relying solely on the sensations that result from movement would be insufficient to quickly adjust and update future motor plans due to the inherent delays in the communication and processing within the central nervous system. There is strong behavioral evidence that to ensure sufficient control the brain uses information about the issued motor commands to form a prediction of the expected sensations that result from body motion. Despite this evidence, it remains largely unknown how the brain combines these predictions of sensory feedback with actual motion-induced sensations for movement control and self-movement perception. This CAREER proposal, through student involvement and outreach activities, lays the foundation for a long-term research and educational career to address these gaps in knowledge. Utilizing a diverse set of techniques, the investigator will systematically examine the contributions of actual and predicted sensory feedback to upper limb behavior.Corollary discharge (CD, also referred to as efference copy) is the internal duplicate of a motor command made at the same time the motor signal is generated. This signal is used to predict the future state of the body and the expected sensory consequences due to movement. The integration of this internal state information with delayed sensory signals is critical for accurate movement control and motion perception. However, little is known about the properties of this signal in humans or how this internal movement information is integrated with reafferent sensory feedback. Despite being poorly understood, internal state estimation remains a critical feature of computational models of limb movement and feedforward control. To directly address the current gaps in knowledge, the proposed studies aim to (1) quantify the accuracy and sensitivity of proprioception and internal limb state estimation, (2) computationally describe how these signals are combined to aid perception and motor coordination, and (3) determine the causal relationships between behavior and the neural processing of these signals through the application of transcranial magnetic stimulation to areas within the parietal cortex and cerebellum. Pursuing the project goals will utilize different techniques (computational modeling, noninvasive neural stimulation and quantitative behavioral analysis) in order to advance the computational frameworks for sensorimotor integration and control. Increasing the understanding of this neural integration could potentially (1) provide the foundation for understanding how actual and predicted sensory information contribute to complex behaviors (e.g., eye-hand and bimanual coordination), (2) help define the constraints (e.g., timing and acuity) of the different sensory information required for effective neural prostheses and brain?machine interface control and (3) assist in distinguishing the basis of feedforward motor control deficits in several neurological diseases. Importantly, the project promotes the inclusion and training of students from various backgrounds, particularly minority students, and encourages the outreach and dissemination of the scientific research to a broad spectrum of participants within the community, from grade school students to retired individuals.