OCULAR MOTOR FUNCTION IN HUNTINGTON'S DISEASE

我们研究的长期目标是更好地了解 正常和异常的眼运动和前庭功能的机制 在亨廷顿病（HD）中的作用。 我们最近的研究表明， HD患者在产生“意志”方面存在选择性缺陷， 扫视（例如，反扫视和预测性扫视）以及 抑制对新刺激的不需要的反射性扫视。 本建议的第一个目的是发展更微妙的方式， 测试和量化扫视的更高水平控制， 追踪眼球运动 一个新的扫视范例将被测试， 扫视的幅度和潜伏期，同时进行扫视序列， 一系列看到或记住的目标。 我们还将比较增益和 平滑的追踪运动对刺激的时间安排， 反应（全场刺激的突然移动）， 产生更多的意志反应（跟踪一个小目标上移动， 视觉上丰富的背景）。 我们预计HD患者会在更多方面表现出缺陷， 意志的追求。 第二个目的是评估进一步的姿势和 HD患者的前庭控制。 使用移动平台 姿势图，我们将测量HD患者的姿势控制， 并与前庭眼反射测量结果进行比较。 我们 将检验HD患者的共济失调与 前庭信息的中枢处理障碍。 我们所有的 测试结果将与神经系统的测试结果相关联， 心理功能和核磁共振成像研究。

The long-term objective of our research is to better understand the mechanisms underlying both normal and abnormal ocular motor and vestibular function in Huntington's Disease (HD). Our recent research has shown that patients with HD have selective deficits in generating "volitional" saccades (e.g. antisaccades and predictive saccades) as well as defects in suppression of unwanted reflexive saccades in response to novel stimuli. The first aim of the present proposal is to develop more subtle ways of testing and quantifying the higher level control of saccadic and also pursuit eye movements. A new saccade paradigm will be tested that measures the amplitude and latency of saccades while making sequences of saccades to a series of seen or remembered targets. We will also compare the gain and timing of smooth pursuit movements to stimuli that produce a more reflexive response (sudden movement of a full field stimulus) with stimuli that produce a more volitional response (tracking of a small target moving on a visually rich background). We expect HD patients to show deficits in more volitional pursuit. The second aim is to evaluate further postural and vestibular control in patients with HD. Using moving platform posturography, we will measure postural control in patients with HD and compare the results with measurement of their vestibulo-ocular reflex. We will test the hypothesis that the ataxia of HD patients is related to a disorder of central processing of vestibular information. All of our testing results will be correlated with results of tests of neurological and psychological function and MRI studies.