Howard Christina J, Masom David, Holcombe Alex O
Division of Psychology, Nottingham Trent University, Burton Street, Nottingham NG1 4BU, UK.
Vision Res. 2011 Sep 1;51(17):1907-19. doi: 10.1016/j.visres.2011.07.001. Epub 2011 Jul 6.
In the multiple object tracking (MOT) task, observers can typically keep track of up to four moving objects. Little is known however about the extent to which object motion is used by observers during MOT. For example, direction and speed might be used to anticipate future positions. We here ask to what extent position reports lag behind targets or instead correspond to extrapolated positions. Using a range of different motion trajectory patterns, observers tracked 1-4 targets among distracters and reported the final position of one of the targets. On average, reports corresponded to previous positions rather than the final position. This lag varied across conditions from around 10 to 70ms of the object's trajectory. Although some have suggested that extrapolation occurs during MOT, we find no evidence of anticipation of future positions of targets. The significant increase in lag with speed of the object is consistent with slow or intermittent updating of object positions during tracking.
在多目标跟踪（MOT）任务中，观察者通常能够跟踪多达四个移动目标。然而，关于观察者在MOT过程中利用目标运动的程度，我们所知甚少。例如，方向和速度可能被用来预测未来位置。我们在此探讨位置报告在多大程度上滞后于目标，或者相反，与外推位置相对应。使用一系列不同的运动轨迹模式，观察者在干扰物中跟踪1至4个目标，并报告其中一个目标的最终位置。平均而言，报告对应于先前位置而非最终位置。这种滞后在不同条件下有所不同，约为目标轨迹的10至70毫秒。尽管有人认为外推在MOT过程中会发生，但我们没有发现预测目标未来位置的证据。随着目标速度的增加，滞后显著增加，这与跟踪过程中目标位置的缓慢或间歇性更新是一致的。
