Tian J R, Zee D S, Lasker A G, Folstein S E
Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD.
Neurology. 1991 Jun;41(6):875-81. doi: 10.1212/wnl.41.6.875.
We compared saccadic eye movements in 21 patients with Huntington's disease (HD) and 21 normal subjects. In a predictive tracking task, HD patients were unable to anticipate normally the timing and location of a visual target that alternated its position predictably (+/- 10 degrees, 0.5 Hz; mean latency of +170 msec in HD and -78 msec in normal subjects). HD patients and normal subjects, however, showed comparable decreases in saccade latency (110 msec in HD, 124 msec in normal subjects) when the fixation target was turned off 200 msec before (gap task) versus 200 msec after (overlap task) the appearance of an unexpected peripheral stimulus. Taken together, these findings support the idea that HD patients show greater defects in initiating internally generated than in initiating externally triggered saccades. This dichotomy is likely due to involvement of frontal lobe--basal ganglia structures in HD, with relative sparing of parietal--superior collicular pathways.
我们比较了21例亨廷顿舞蹈症（HD）患者和21名正常受试者的眼球跳动。在一项预测性跟踪任务中，HD患者无法正常预测视觉目标位置可预测交替（±10度，0.5赫兹）的时间和位置（HD患者的平均延迟为+170毫秒，正常受试者为-78毫秒）。然而，当在意外周边刺激出现前200毫秒（间隙任务）与出现后200毫秒（重叠任务）关闭固定目标时，HD患者和正常受试者的扫视潜伏期均出现了类似程度的下降（HD患者为110毫秒，正常受试者为124毫秒）。综合来看，这些发现支持了这样一种观点，即HD患者在发起内源性扫视方面比发起外源性触发扫视存在更大缺陷。这种二分法可能是由于HD中额叶 - 基底神经节结构受累，而顶叶 - 上丘通路相对保留。
