Spatial Interaction of Otolith mediated Collic Reflexes

耳石介导的绞痛反射的空间相互作用

• 批准号: 7312819
• 负责人: Greg Thomas Gdowski
• 金额: $ 22.66万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7312819
• 关键词: Saimiri; antidromic impulse; behavior test; behavioral /social science research tag; electromyography; electrostimulus; head movements; motion perception; neck; neural information processing; otocyst /otolith; posture; psychomotor function; space perception; vestibular pathway; vestibuloocular reflex; Saimiri; antidromic impulse; behavior test; behavioral /social science research tag; electromyography; electrostimulus; head movements; motion perception; neck; neural information processing; otocyst /otolith; posture; psychomotor function; space perception; vestibular pathway; vestibuloocular reflex

Project 2, Spatial interactions of otolith mediated collic reflexes (Gdowski, PI), asks how the vestibular signals arising from otolith endorgans, which detect horizontal and vertical acceleration, are used to activate neck muscles that reflexively reorient the head. Cervical injury affects 1 million U.S. lives annually, yet we are just beginning to understand how postural reflexes that evolved to protect the neck are controlled. Progress has been hampered, in part, because of the complexity of the neck musculature and its multiple functions in reorienting gaze and reflexively stabilizing the head with respect to the body. Vestibulospinal (VS) pathways are richly innervated by converging otolith inputs. The signals carried by the VS pathways bilaterally and reciprocally activate neck muscles during static tilts and linear translations of the body. We hypothesize that neck muscle activity will exhibit spatial tuning when combinations of tilt and translation are imposed on the body sequentially throughout 3-D space. We further hypothesize that the spatial tuning of neck muscles is causally related to the spatial tuning of responses of vestibulospinal neurons. To test these hypotheses experiments will be carried out in squirrel monkeys in which the electromyography (EMG) of neck muscles and neural activity of VS pathways are recorded. Different combinations of tilt and translation will be imposed on the body throughout 3-D space. Initial experiments will determine if specific groups of neck muscles exhibit spatial tuning during tilts and translations in different directions. The second set of experiments will determine if VS neurons, recorded in the vestibular nuclei, exhibit spatial tuned responses during tilts and translations in different directions. VS neurons will be identified physiologically by antidromic stimulation. In addition, neck EMG activity and VS neuron activity will be recorded simultaneously so that spike-triggered averaging (SpikeTA) can be used to identify functional relationships between neural discharge and EMG activity. The spatial tuning of each neck muscle will be compared to the collective spatial tuning properties of sub-populations of VS neurons identified as functionally-related to the neck muscle (identified through SpikeTA). This analysis will be used to determine if the spatially-tuned neck EMG activity are causally related to the spatial properties of VS pathways. In the final experiments, the head will be allowed to move in the direction of translation while the responses of VS neurons are recorded. The directions of translation will be chosen based upon direction that maximally activates the neuron. These data will used us to determine how otolith signals are modified during the execution of collic reflexes. The results of these experiments are significant to our understanding of how otolith signals influence the orientation of the head during normal activities such as locomotion.

项目2，耳石介导的胶质反射（GDOWSKI，PI）的空间相互作用询问如何使用水平和垂直加速的耳石内虫引起的前庭信号来激活头部反射能使头部重新定位的颈部肌肉。宫颈损伤每年影响100万个美国的生活，但我们才开始了解如何控制以保护颈部的姿势反射。由于颈部肌肉组织的复杂性及其在重新定位凝视和反射稳定头部相对于身体方面的多种功能，因此进步受到了阻碍。前庭脊髓（VS）途径通过收敛的耳石输入来丰富地支配。 VS途径携带的信号 在静态倾斜和人体线性翻译过程中，双侧和相互激活颈部肌肉。我们假设颈部肌肉活动将表现出空间调节，而倾斜和翻译的组合在整个3D空间中依次施加在身体上。我们进一步假设，颈部肌肉的空间调节与前庭脊髓神经元反应的空间调整有关。为了测试这些假设，将在松鼠猴中进行实验，其中记录了颈部肌肉的肌电图（EMG）和VS途径的神经活动。倾斜和翻译的不同组合将在整个3D空间内施加在体内。最初的实验将确定特定的颈部肌肉组是否在倾斜期间表现出空间调节和朝不同方向的翻译表现出来。第二组 实验将确定在前庭核中记录的VS神经元是否在倾斜期间显示出空间调节的响应，并在不同方向上翻译。 VS神经元将通过抗体刺激在生理上鉴定。此外，将同时记录颈部EMG活性和VS神经元活性，以便可以使用尖峰触发的平均（Spiketa）来识别神经放电和EMG活性之间的功能关系。每个颈部肌肉的空间调节将与与颈部肌肉功能相关的VS神经元的子组合的集体空间调谐特性进行比较（通过Spiketa鉴定）。该分析将用于确定空间调整的颈部EMG活性是否与VS途径的空间特性有因果关系。在最后的实验中，将允许头部沿翻译方向移动，同时记录与神经元的响应。翻译方向将基于最大激活神经元的方向选择。这些数据将使用我们来确定在执行胶水反射期间如何修改耳石信号。这些实验的结果对于我们对耳石信号如何影响正常活动（例如运动）如何影响头部的方向至关重要。