Brouwer Anne-Marie, Brenner Eli, Smeets Jeroen B J
Neuroscience Institute, Erasmus University Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands.
Exp Brain Res. 2002 Mar;143(2):198-211. doi: 10.1007/s00221-001-0980-x. Epub 2002 Jan 8.
We investigated what information subjects use when trying to hit moving targets. In particular, whether only visual information about the target's position is used to guide the hand to the place of interception or also information about its speed. Subjects hit targets that moved at different constant speeds and disappeared from view after varying amounts of time. This prevented the subjects from updating position information during the time that the target was invisible. Subjects hit further ahead of the disappearing point when the target moved faster, but not as much as they should have on the basis of the target's speed. This could be because more time is needed to perceive and use the correct speed than was available before the target disappeared. It could also be due to a speed-related misperception of the target's final position. The results of a second experiment were more consistent with the latter hypothesis. In a third experiment we moved the background to manipulate the perceived speed. This did not affect the hitting positions. We conclude that subjects respond only to the changing target position. Target speed influences the direction in which the hand moves indirectly, possibly via a speed-related misperception of position.
我们研究了受试者在试图击中移动目标时会使用哪些信息。具体而言,是仅使用关于目标位置的视觉信息来引导手部到达拦截位置,还是也使用关于其速度的信息。受试者击打以不同恒定速度移动且在不同时间后消失在视野中的目标。这使得受试者在目标不可见的时间段内无法更新位置信息。当目标移动速度更快时,受试者会在消失点前方更远的位置击打,但并没有达到基于目标速度所应达到的程度。这可能是因为感知和使用正确速度所需的时间比目标消失前可用的时间更多。这也可能是由于与速度相关的对目标最终位置的误判。第二个实验的结果更符合后一种假设。在第三个实验中,我们移动背景以操纵感知到的速度。这并未影响击打位置。我们得出结论,受试者仅对变化的目标位置做出反应。目标速度可能通过与速度相关的位置误判间接影响手部移动的方向。