CANAL AND UTRICULAR SENSITIVITIES AND EFFERENT INFLUENCE

运河和椭圆囊的敏感性和传出影响

• 批准号: 2126171
• 负责人: STEVEN F MYERS
• 金额: $ 9.46万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-07-01 至 1997-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2126171
• 关键词: Rana; action potentials; afferent nerve; alternatives to animals in research; axon; balance; efferent nerve; fluorescence microscopy; fluorescent dye /probe; labyrinth; microelectrodes; neurophysiology; vestibular apparatus

The long range goal of the proposed project is to provide a better understanding of how the efferent vestibular system is involved in the overall balance function of the inner ear. Vestibular afferent neurons transmit very accurate head-movement information from the inner ear to the brain. Efferent neurons allow the brain to modify information coming from the inner ear. Despite numerous studies on the efferent vestibular system, the influence of this system on incoming afferent information remains obscure. The efferent system is known to be "turned on" in anticipation of active movements. Therefore, it seems likely that it functions in some way to optimize our sensing of a motion, which in turn will optimize balance and coordination. Previous studies have indicated that the efferent system may help prevent the vestibular afferent neurons from being over-driven by strong movement stimuli. Part of this effect involves an apparent reduction in afferent sensitivity. However, previous investigators have not quantitatively addressed afferent sensitivity with respect to the background "noise" present in the neuron's discharge activity. Because the efferent system can reduce this temporal noise level (coefficient of variation in interspike intervals), it is quite possible that the overall effect of the efferent system on many afferent neurons is to increase their sensitivity. Aside from sensitivity, other aspects of vestibular afferent response dynamics may be influenced by the efferent system. The dynamics of an afferent neuron's response to a rotational motion reflect how much acceleration versus velocity information is carried by that particular neuron. During natural, quick head movements, the efferent system may alter, in some cases, afferent response dynamics in favor of acceleration or may optimize linearity of the velocity response in other cases. The proposed research will use single-unit, microelectrode recording techniques in conjunction with efferent stimulation and pharmacological manipulations. Evoked responses will be analyzed both in the time and frequency domains. A thorough analysis will be made of spike train noise and afferent response dynamics in the presence and absence of efferent stimulation. These investigations should lead to a more quantitative understanding of efferent vestibular effects on afferent sensitivity and responses to rotational movements than currently exists. This in turn will likely provide new insights into normal vestibular function as well as the role of the efferent vestibular system in human balance disorders and recovery from vestibular injury.

拟议项目的远距离目标是提供更好的 了解传出前庭系统如何参与 内耳的总体平衡功能。 前庭传入神经元 从内耳传输非常准确的头部移动信息 大脑。 传出的神经元使大脑可以修改信息的到来 从内耳。 尽管有许多关于发出前庭的研究 系统，该系统对传入信息的影响 仍然晦涩难懂。 众所周知，传出系统已被“打开” 预期主动运动。 因此，似乎很可能 以某种方式发挥作用来优化我们对运动的感觉，而这又 将优化平衡和协调。 先前的研究表明 传出系统可能有助于防止前庭传入神经元 由于被强大的运动刺激而被过度驱动。 该效果的一部分 涉及传入灵敏度的明显降低。 然而， 以前的调查人员尚未定量解决传入 关于背景“噪声”的敏感性 神经元的排出活动。 因为传出系统可以减少这一点 时间噪声水平（升华间隔的变化系数）， 传出系统的总体影响很可能 许多传入的神经元是为了提高其敏感性。 除了 灵敏度，前庭传入响应动态的其他方面可能 受传出系统的影响。 传入的动力 神经元对旋转运动的反应反映了多少加速度 该特定神经元携带的速度信息与速度信息。 期间 自然，快速的头部运动，传出系统可能会改变 情况，传入的响应动态支持加速或可能 在其他情况下优化速度响应的线性性。 提议 研究将使用单单元，微电极记录技术 与传出刺激和药理操作的结合。 诱发响应将在时间域和频域中分析。 将对尖峰火车的噪音和传入进行彻底的分析 在存在和不存在传出刺激的情况下响应动力学。 这些调查应导致对 前庭对传入敏感性的影响和对 旋转运动比目前存在的运动。 反过来可能 提供有关正常前庭功能以及角色的新见解 人类平衡障碍和康复的传出前庭系统 因前庭损伤。