Department of Human Perception, Cognition and Action, Max Planck Institute for Biological Cybernetics, Tübingen, Germany,
Exp Brain Res. 2013 Oct;230(3):271-81. doi: 10.1007/s00221-013-3651-9. Epub 2013 Aug 10.
We investigate how smooth pursuit eye movements affect the latencies of task-switching saccades. Participants had to alternate their foveal vision between a continuous pursuit task in the display center and a discrete object discrimination task in the periphery. The pursuit task was either carried out by following the target with the eyes only (ocular) or by steering an on-screen cursor with a joystick (oculomanual). We measured participants' saccadic reaction times (SRTs) when foveal vision was shifted from the pursuit task to the discrimination task and back to the pursuit task. Our results show asymmetries in SRTs depending on the movement direction of the pursuit target: SRTs were generally shorter in the direction of pursuit. Specifically, SRTs from the pursuit target were shorter when the discrimination object appeared in the motion direction. SRTs to pursuit were shorter when the pursuit target moved away from the current fixation location. This result was independent of the type of smooth pursuit behavior that was performed by participants (ocular/oculomanual). The effects are discussed in regard to asymmetries in attention and processes that suppress saccades at the onset of pursuit.
我们研究了平稳追踪眼球运动如何影响任务转换扫视的潜伏期。参与者必须在显示器中心的连续追踪任务和外围的离散物体辨别任务之间交替注视中央。追踪任务要么只用眼睛（眼动）跟踪目标，要么用操纵杆控制屏幕上的光标（眼手动）。当注视中央从追踪任务转移到辨别任务再返回追踪任务时，我们测量了参与者的扫视反应时间（SRT）。我们的结果表明，SRT 取决于追踪目标的运动方向存在不对称性：通常情况下，追踪方向上的 SRT 更短。具体来说，当辨别物体出现在运动方向上时，来自追踪目标的 SRT 更短。当追踪目标远离当前注视位置时，对追踪的 SRT 更短。这一结果与参与者进行的平稳追踪行为类型（眼动/眼手动）无关。该结果与注意力不对称以及在开始追踪时抑制扫视的过程有关。
