Developing an Experimental and Computational Framework for Studying Neural Representations of Tactile Motion on the Hand

开发用于研究手部触觉运动神经表征的实验和计算框架

• 批准号: 10732095
• 负责人: Manuel Gomez-Ramirez
• 金额: $ 21.48万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-08 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10732095
• 关键词: Animals; Area; Bayesian Analysis; Behavior; Behavioral; Behavioral Paradigm; Body part; Brain; Cells; Chronic; Cognitive; Computer Models; Cues; Cutaneous; Data; Discrimination; Feedback; Fingers; Funding; Goals; Grant; Hand; Human; Judgment; Knowledge; Learning; Location; Medial; Mediating; Modeling; Molecular Conformation; Motion; Motion Perception; Motor; Neurons; Pattern; Perception; Phase; Play; Population; Positioning Attribute; Posture; Proprioception; Protocols documentation; Psychophysics; Role; Signal Transduction; Skin; Somatosensory Cortex; Source; Speed; Stimulus; Tactile; Temporal Lobe; Testing; Thumb structure; Time; Touch sensation; Training; Visual Motion; Work; analog; computer framework; density; experimental study; flexibility; grasp; haptics; indexing; neural; neural model; neuromechanism; neurophysiology; neurotransmission; nonhuman primate; object motion; response; sensory feedback; somatosensory; tactile stimulation

PROJECT SUMMARY Dexterous manipulation of objects relies on brain computations that integrate neural signals encoding tactile signals on the skin with the proprioceptive state of the hand. In particular, neural ensembles that encode tactile motion on the skin are critical because they provide feedback signals to motor planning areas to indicate whether an object is slipping from the hand. Although we have a good understanding of how tactile motion signals are represented in the brain, this knowledge has been accrued from studies that placed the hand in a fixed position. Indeed, all studies that have investigated tactile motion mechanisms at the single-cell level have done so in animals not performing a motion discrimination task, and with their hands placed in a fixed posture. These studies show that tactile motion can be represented in area 1 by cells that integrate different tactile cues of the object (e.g., direction, speed, and saliency). However, our recent work in humans shows that perception of tactile motion on a finger is modulated by the proprioceptive state of the hand, and the body part location in which motion judgements are made relative to (i.e., the reference frame). These findings indicate that current models of tactile motion require major revisions. That is, neural models of tactile motion should take into account how motion representations in touch are transformed by proprioception and/or reference frame signals. Thus, the overarching goal of this application is to determine the neural areas and mechanisms that generate reference frame-specific representations of tactile motion. Key to determining the single-cell mechanisms that mediate reference frame-specific representations of tactile motion is to record activity in non-human primates (NHPs) discriminating tactile motion stimuli in different reference frames, and with their hands placed in different postures. Unfortunately, our field does not have an established paradigm, or training regime, to study these motion mechanisms in a NHP. In Aim I, we develop a behavioral paradigm to train NHPs to discriminate the motion direction of stimulus on a finger (e.g., index finger) in different reference frames (e.g., relative to the center of the body, or the thumb), while their hands are placed different proprioceptive states (e.g., pronated vs. supinated). In Aim II, we will record single-unit activity in somatosensory cortex (area 1) in trained NHPs to determine the neural computations that generate reference frame-specific representations of tactile motion. Our behavioral experiments will test that perceptual representations of tactile motion are conserved across NHPs and humans, demonstrating that NHPs are a viable species to study neural mechanisms of tactile motion at the single cell level. Our neurophysiology experiments will test whether motion selective neurons in area 1, the tactile analogue of medial temporal (MT) cortex for visual motion, flexibly represent motion in different reference frames. This project will demonstrate, for the first time, behavioral and neurophysiological evidence of NHPs performing tactile motion discrimination tasks, a crucial prerequisite for a competitive R01-type application.

项目摘要 灵巧对物体的操纵依赖于整合神经信号编码触觉的大脑计算 皮肤上的信号具有手的本体感受状态。特别是，编码触觉的神经合奏 皮肤上的运动至关重要，因为它们为运动规划区域提供反馈信号，以指示是否表示是否 一个物体从手中滑落。尽管我们对触觉运动信号的良好了解 在大脑中代表，这些知识是从将手放置在固定位置的研究中得到的。 确实，所有研究了单细胞水平上触觉运动机制的研究都这样做 动物没有执行运动歧视任务，并将其置于固定的姿势中。这些研究 证明触觉运动可以通过整合对象的不同触觉提示的细胞在区域1中表示 （例如，方向，速度和显着性）。但是，我们最近在人类中的工作表明了对触觉运动的看法 手指在手指上是由手的本体感受状态和身体部位的位置调节的 判断是相对于（即参考框架）做出的。这些发现表明当前的模型 触觉运动需要重大修改。也就是说，触觉运动的神经模型应考虑 接触中的运动表示通过本体感受和/或参考框架信号转换。因此， 该应用程序的总体目标是确定产生的神经区域和机制 触觉运动的特定于参考框架的表示。 确定介导触觉的参考框架特定表示的单细胞机制的关键 运动是记录非人类灵长类动物（NHP）的活动，以区分不同的触觉运动刺激 参考框架，双手放在不同的姿势中。不幸的是，我们的领域没有 建立范式或训练制度，以研究NHP中的这些运动机制。在目标一世中，我们开发了一个 行为范式训练NHP，以区分手指上的刺激的运动方向（例如，食指） 在不同的参考帧（例如，相对于身体的中心或拇指）中，他们的手放在 不同的本体感受状态（例如，刚性与旋转）。在AIM II中，我们将记录单个单元活动 训练有素的NHP中的体感皮质（区域1），以确定产生参考的神经计算 触觉运动的特定于框架的表示。我们的行为实验将测试该知觉 触觉运动的表示在NHP和人类之间是保守的，表明NHP是可行的 在单细胞水平上研究触觉运动的神经机制。我们的神经生理学实验 将测试运动选择性神经元在区域1中是否是视觉中内侧（MT）皮层的触觉类似物 运动，在不同的参考帧中灵活地表示运动。该项目将首次证明 NHP执行触觉运动歧视任务的行为和神经生理学证据，这是至关重要的 竞争性R01型应用程序的先决条件。