Effects of Hindlimb Inputs on the Activity of Vestibular Nucleus Neurons

描述(由申请人提供)：虽然前庭系统在发出头部在太空中移动的信号时非常敏感，但为了控制平衡，还需要关于身体在太空中的方位的额外信息。前庭传入信息是在本体感觉和视觉信息的背景下被解释和塑造的。为了达到稳定的平衡，前庭和腿本体感觉传入信号的整合很可能是至关重要的，因为腿通常是与地面和肢体位置形成前庭脊髓反应的唯一接口。然而，关于肢体传入信号如何与前庭中央通路中的前庭传入信号整合，几乎一无所知。初级阶段 此应用程序的目的是确定躯体感觉肢体输入对活动的影响 前庭神经核(VN)神经元。提出了三个具体目标。在第一个具体目标中，我们将描述后肢运动如何影响VN神经元对头部旋转激活迷路受体的反应。此外，我们还将确定哪一类VN神经元对后肢运动敏感。在第二个具体目标中，我们将确定VN神经元是否区分自产生的后肢运动和外部应用的运动。在第三个具体目标中，我们将确定迷路输入丢失后，VN神经元的后肢运动信号是否被放大，并取代丢失的前庭信号。这些实验有望促进对前庭中央通路肢体躯体感觉输入处理的理解，并最终可能导致前庭疾病患者的新疗法。

DESCRIPTION (provided by applicant): Although the vestibular system has exquisite sensitivity in signaling head movement in space, additional information about the orientation of the body in space is needed for the control of balance. Vestibular afferent information is interpreted and shaped in the context of proprioceptive and visual information. To achieve stable balance, it is likely that integration of vestibular and leg proprioceptive afferent signalsis critical, since the legs typically serve as the sole interface with the ground and limb position shapes vestibulospinal responses. However, virtually nothing is known about how limb afferent signals are integrated with vestibular afferent signals in central vestibular pathways. The primary goal of this application is to determine the influence of somatosensory limb inputs on the activity of vestibular nucleus (VN) neurons. Three specific aims are proposed. In the first specific aim, we will characterize how hindlimb movements affect the responses of VN neurons to rotations of the head that activate labyrinthine receptors. We will additionally determine which subclass of VN neurons is sensitive to hindlimb movement. In the second specific aim, we will determine whether VN neurons differentiate between self-generated hindlimb movement and externally applied movement. In the third specific aim, we will determine whether hindlimb movement signals to VN neurons are amplified following loss of labyrinthine inputs, and substitute for the lost vestibular signals. These experiments are expected to advance understanding regarding the processing of limb somatosensory inputs in central vestibular pathways and may ultimately lead to novel therapies for vestibulopathic patients.