The Concurrent Programming of Saccades

Sequences of saccades have been shown to be prepared concurrently however it remains unclear exactly what aspects of those saccades are programmed in parallel. To examine this participants were asked to make one or two target-driven saccades: a reflexive saccade; a voluntary saccade; a reflexive then a voluntary saccade; or vice versa. During the first response the position of a second target was manipulated. The new location of the second saccade target was found to impact on second saccade latencies and second saccade accuracy showing that some aspects of the second saccade program are prepared in parallel with the first. However, differences were found in the specific pattern of effects for each sequence type. These differences fit well within a general framework for saccade control in which a common priority map for saccade control is computed and the influence of saccade programs on one another depends not so much on the types of saccade being produced but rather on the rate at which their programs develop.

已有研究表明，眼跳（saccades）序列可被并行准备，但目前仍未明确这类眼跳的哪些具体特征会被并行编程。为探究这一科学问题，实验要求被试完成1次或2次靶驱动眼跳任务：分别为反射性眼跳（reflexive saccade）、自主性眼跳（voluntary saccade）、先反射后自主性眼跳，或二者顺序相反。在首次眼跳反应阶段，研究者会对第二个目标的位置进行操控。结果显示，第二个眼跳目标的新位置会影响第二个眼跳的潜伏期与准确性，这表明第二个眼跳程序的部分特征可与第一个眼跳程序并行准备。不过，不同眼跳序列类型对应的效应模式存在显著差异。这类差异与眼跳控制的通用理论框架高度契合：该框架提出，眼跳控制需先计算出一个通用的优先级地图（priority map），且眼跳程序之间的相互影响，并非取决于所生成眼跳的类型，而是取决于其程序的发育速率。