Kingstone A, Klein R M
Center for Neuroscience, University of California, Davis 95616-8768.
J Exp Psychol Hum Percept Perform. 1993 Dec;19(6):1251-65. doi: 10.1037//0096-1523.19.6.1251.
Saccadic reaction time (RT) is reduced when a fixation stimulus is extinguished 200 ms before a target appears. An attentional predisengagement theory (APT) may explain this gap effect: When covert attention is engaged (e.g., on fixation), the saccadic system is inhibited and RT is delayed; when the attended stimulus is extinguished, attention is disengaged, the inhibition is removed, and RT is facilitated. In 3 experiments covert attention was endogenously or exogenously cued to an object on the vertical meridian. Onset of a saccadic target on the horizontal meridian could be preceded by the offset of an attended or unattended object. Contrary to APT, RTs were identical after attended and unattended offsets. Results suggest that the gap effect has 2 components, and covert visual attention plays no role. One component is motor system preparation; the other is a fixation offset effect specific to the oculomotor system.
当在目标出现前200毫秒熄灭注视刺激时，扫视反应时（RT）会缩短。一种注意力预先脱离理论（APT）或许可以解释这种间隙效应：当内隐注意力被吸引（例如，处于注视状态）时，扫视系统受到抑制且反应时延迟；当被关注的刺激消失时，注意力脱离，抑制解除，反应时加快。在3个实验中，内隐注意力通过内源性或外源性线索指向垂直子午线上的一个物体。水平子午线上扫视目标的出现可能在被关注或未被关注物体消失之后。与APT相反，被关注和未被关注物体消失后的反应时是相同的。结果表明，间隙效应有两个成分，内隐视觉注意力不起作用。一个成分是运动系统准备；另一个是眼动系统特有的注视偏移效应。
