SHORT LATENCY OCULAR-FOLLOWING RESPONSES IN MAN
SHORT LATENCY OCULAR-FOLLOWING RESPONSES IN MAN
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DOI：
10.1017/s0952523800000158
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发表时间：
1990-08-01
影响因子：
1.9
通讯作者：
MILES, FA
中科院分区：
文献类型：
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作者：
GELLMAN, RS;CARL, JR;MILES, FA
在受试者中研究了视觉场景的意外运动所引起的眼球跟随反应。反应潜伏期随着刺激类型的不同而不同，并随着刺激速度的增加而系统性地减少，但与猴子不同的是，反应潜伏期并不完全由正弦波刺激产生的时间频率决定。最小潜伏期(70-75ms)比报道的其他视觉驱动眼动的潜伏期要短得多。在所使用的范围内，对正弦波刺激的反应的大小随刺激速度而显著变化，而仅随空间频率而变化很小。当空间频率归一化时，所有反应对时间频率的依赖程度相同(峰值在16赫兹的带通特性)，这表明在整个研究范围内，时间频率而不是速度本身是限制因素。这表明潜在的运动检测器对与场景运动相关联的亮度的局部变化做出响应。眼球跳动后的场景运动平均是600毫秒后运动的效果的两倍：跳视后的增强。在场景的眼跳样变化之后，增强效果较差，这本身就引起了微弱的眼球追随，这是在真正的眼跳之后看不到的。我们认为，存在中枢机制，一方面防止眼球跟随系统跟踪眼跳造成的视觉干扰，但另一方面促进对任何后续干扰的跟踪，从而帮助抑制扫视后漂移。将视觉场景划分为中央区域和外围区域表明，外围区域的运动可以对中心区域的运动引起的眼球跟随反应产生微弱的调制影响。我们认为，这可能有助于移动的观察者将他/她的眼睛稳定在附近的静止物体上。
The ocular-following responses elicited by unexpected movements of the visual scene were studied in human subjects. Response latencies varied with the type of stimulus and decreased systematically with increasing stimulus speed but, unlike those of monkeys, were not solely determined by the temporal frequency generated by sine-wave stimuli. Minimum latencies (70-75 ms) were considerably shorter than those reported for other visually driven eye movements. The magnitude of the responses to sine-wave stimuli changed markedly with stimulus speed and only slightly with spatial frequency over the ranges used. When normalized with respect to spatial frequency, all responses shared the same dependence on temporal frequency (band-pass characteristics with a peak at 16 Hz), indicating that temporal frequency, rather than speed per se, was the limiting factor over the entire range examined. This suggest that the underlying motion detectors respond to local changes in luminance associated with the motion of the scene. Movements of the scene in the immediate wake of a saccadic eye movement were on average twice as effective as movements 600 ms later: post-saccadic enchancement. Less enhancement was seen in the wake of saccade-like shifts of the scene, which themselves elicited weak ocular following, something not seen in the wake of real saccades. We suggest that there are central mechanisms that, on the one hand, prevent the ocular-following system from tracking the visual disturbances created by saccades, but, on the other, promote tracking of any subsequent disturbance and thereby help to suppress post-saccadic drift. Partitioning the visual scene into central and peripheral regions revealed that motion in the periphery can exert a weak modulatory influence on ocular-following responses resulting from motion at the center. We suggest that this may help the moving observer to stabilize his/her eyes on nearby stationary objects.