Effects of Hindlimb Inputs on the Activity of Vestibular Nucleus Neurons

描述（由申请人提供）：虽然前庭系统在信号头部在空间中的运动方面具有敏锐的灵敏度，但需要额外的关于身体在空间中的方向的信息来控制平衡。前庭传入信息在本体感觉和视觉信息的背景下被解释和塑造。为了达到稳定的平衡，前庭和腿部本体感觉传入信号的整合可能至关重要，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，对于前庭中枢通路中肢体传入信号与前庭传入信号是如何整合的，我们实际上一无所知。主

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.