Boch R, Fischer B
Exp Brain Res. 1986;63(3):487-94. doi: 10.1007/BF00237472.
Express-saccades, i.e. goal directed eye movements with extremely short saccadic reaction times (SRT) have recently been observed in rhesus monkey (70-80 ms) and human subjects (around 100 ms). In the gap task which has been used so far, a central fixation point (Fp) was turned off a short time before a new target (Tg) in the near periphery was presented. Therefore, express-saccades occurred when the goal of fixation was no longer visible. To determine whether or not the absence of the Fp is a necessary condition for the execution of an express-saccade, we used an overlap task in which the monkeys had to change the direction of gaze in the presence of the Fp. The results for this overlap task were compared to those found in the gap task. Three major observations have emerged from the present study. Even though the Fp remained visible, a suddenly appearing peripheral target could be reached by an express-saccade. Express-saccades persisted if the location as well as the time of the appearance of the target was randomized. It appears that for an express-saccade to occur, the process of interruption of previous active fixation must be completed at the time when a new target becomes visible. The spectrum of the monkey's saccadic reaction times contains at least three different peaks: express-saccades with reaction times below 100 ms, fast regular saccades with reaction times around 130 ms, and slow regular saccades with reaction times around 180 ms.
快速扫视，即具有极短扫视反应时间（SRT）的目标导向性眼球运动，最近在恒河猴（70 - 80毫秒）和人类受试者（约100毫秒）中被观察到。在迄今为止所使用的间隙任务中，中央注视点（Fp）在近周边的新目标（Tg）呈现之前的短时间被关闭。因此，当注视目标不再可见时会出现快速扫视。为了确定Fp的缺失是否是执行快速扫视的必要条件，我们使用了一种重叠任务，在该任务中猴子必须在Fp存在的情况下改变注视方向。将该重叠任务的结果与间隙任务中的结果进行比较。本研究出现了三个主要观察结果。即使Fp仍然可见，突然出现的周边目标也可以通过快速扫视到达。如果目标出现的位置和时间是随机的，快速扫视仍然会持续出现。似乎为了出现快速扫视，在新目标可见时，先前主动注视的中断过程必须完成。猴子扫视反应时间的频谱至少包含三个不同的峰值：反应时间低于100毫秒的快速扫视、反应时间约为130毫秒的快速规则扫视以及反应时间约为180毫秒的慢速规则扫视。
