SENSORY-MOTOR ADAPTIVE MECHANISMS IN EQUILIBRIUM CONTROL

控制老年人的平衡是一项重要的公共健康 令人担忧，因为老龄化伴随着两者发病率的增加 头晕和摔倒。前庭系统在维持 通过各种姿势和方向的反射来保持平衡。其中之一 它的主要功能是前庭-眼睛反射(VOR)，它产生 头部运动过程中眼睛的补偿性旋转，以便 保持眼睛对视觉目标的注视，从而保持稳定的视网膜 图像。VOR由两种头部运动激活；角度( Avor)，由半规管驱动，和线性(LVOR)，由 耳石。VOR的一个重要特征是它能够自适应地 因视觉-前庭失配时间延长而调整表现 在头部运动时。此外，最近的证据表明， VOR还受瞬时观看条件(例如目标)的调制 距离和凝视)，更多的是在LVOR而不是Avor。这个项目 重点关注VOR，因为它是最直接和最容易访问的行为 由此可以推导出关于前庭功能的机械推论。 通常，与Avor相比，LVOR受到的关注较少。适应性 可塑性仅在Avor中被证明，并且仍未被开发。 在左轮室。对衰老的研究也仅限于Avor。在 在过去的支持期，发现了年龄依赖性的渐进性恶化 在热情及其适应能力上，尤其是在受到高压力时 头部速度和频率。我们现在把注意力转向人类 爱情者与视觉追随者的关系与小说 不同年龄段的适应机制。新技术将是 用来研究这些函数，以便定义它们的基本 性能和塑料特性。我们还将强调LVOR和 视觉驱动的自适应机制，以发现限制和 随着年龄的增长而恶化。我们假设LVOR将超过 对衰老比热情更敏感，并认为两者都有全面的研究 VORS将允许我们推断基本利益的机制以及 那些与年龄相关的不平衡潜在的头晕和 瀑布。

The control of equilibrium in the elderly is an important public health concern because aging is accompanied by an increasing incidence of both dizziness and falls. The vestibular system is crucial in maintaining equilibrium through a variety of postural and orienting reflexes. One of its major functions is the vestibulo-ocular reflex (VOR), which generates compensatory rotations of the eyes during head movements in order to maintain ocular fixation on visual targets, and therefore a stable retinal image. The VOR is activated by two kinds of head motion; angular (the AVOR), driven by the semicircular canals, and linear (the LVOR), driven by the otoliths. An important feature of the VOR is its ability to adaptively modify performance in response to prolonged visual-vestibular mismatch during head movements. In addition, recent evidence has demonstrated that the VOR is also modulated by instantaneous viewing conditions (e.g. target distance and gaze), more so in the LVOR than the AVOR. This project focuses on the VOR because it is the most direct and accessible behavior from which mechanistic inferences about vestibular function can be derived. The LVOR has generally received less attention than the AVOR. Adaptive plasticity has only been demonstrated in the AVOR, and remains unexplored in the LVOR. Studies on aging have also been limited to the AVOR. In the past support period, progressive age-dependent deterioration was uncovered in the AVOR and its adaptive capabilities, especially when stressed by high head velocities and frequencies. We now turn our attention to the human LVOR, its relationship with the AVOR and with visual following, and novel adaptive mechanisms in different age groups. New techniques will be employed to study these functions in order to define their basic performance and plastic characteristics. We will also stress the LVOR and visually-driven adaptive mechanisms to uncover limitations and deteriorations with aging. We hypothesize that the LVOR will be more sensitive to aging than the AVOR, and that a comprehensive study of both VORs will allow us to infer mechanisms of fundamental interest as well as those relevant to age-dependent disequilibrium underlying dizziness and falls.