Aivar M Pilar, Brenner Eli, Smeets Jeroen B J
Facultad de Psicología, Universidad Autónoma de Madrid, Campus de Cantoblanco, s/n, 28049 Madrid, Spain.
Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorststraat 9, 1081 BT Amsterdam, The Netherlands.
Vision Res. 2015 May;110(Pt B):166-78. doi: 10.1016/j.visres.2014.10.009. Epub 2014 Oct 20.
To successfully move our hand to a target, it is important not only to consider the target of our movements but also to consider other objects in the environment that may act as obstacles. We previously found that the time needed to respond to a change in position was considerably longer for a displacement of an obstacle than for a displacement of the target (Aivar, Brenner, & Smeets, 2008. Experimental Brain Research 190, 251-264). In that study, the movement constraints imposed by the obstacles differed from those imposed by the target. To examine whether the latency is really different for targets and obstacles, irrespective of any constraints they impose, we modified the design of the previous experiment to make sure that the constraints were matched. In each trial, two aligned 'objects' of the same size were presented at different distances to the left of the initial position of the hand. Each of these objects could either be a target or a gap (opening between two obstacles). Participants were instructed to pass through both objects. All possible combinations of these two objects were tested: gap-target, target-gap, gap-gap, target-target. On some trials one of the objects changed position after movement onset. Participants systematically responded faster to the displacement of a target than to the displacement of a gap at the same location. We conclude that targets are prioritized over obstacles in movement control.
为了成功地将我们的手移动到目标位置，不仅要考虑我们动作的目标，还要考虑环境中可能成为障碍物的其他物体。我们之前发现，对障碍物位移做出反应所需的时间比对目标位移做出反应所需的时间长得多（艾瓦尔、布伦纳和斯米茨，2008年。《实验脑研究》190，251 - 264）。在该研究中，障碍物施加的运动限制与目标施加的不同。为了检验无论目标和障碍物施加何种限制，其反应潜伏期是否真的不同，我们修改了先前实验的设计，以确保限制条件相匹配。在每次试验中，在手部初始位置左侧不同距离处呈现两个大小相同且对齐的“物体”。这些物体中的每一个都可以是目标或间隙（两个障碍物之间的开口）。参与者被指示穿过这两个物体。测试了这两个物体的所有可能组合：间隙 - 目标、目标 - 间隙、间隙 - 间隙、目标 - 目标。在一些试验中，其中一个物体在动作开始后改变了位置。参与者对目标位移的反应系统地比对相同位置间隙位移的反应更快。我们得出结论，在运动控制中，目标比障碍物具有优先级。
