Du Yu, McMillan Neil, Madan Christopher R, Spetch Marcia L, Mou Weimin
Department of Psychology, University of Alberta.
J Exp Psychol Learn Mem Cogn. 2017 Dec;43(12):1857-1871. doi: 10.1037/xlm0000416. Epub 2017 May 15.
The authors investigated how humans use multiple landmarks to locate a goal. Participants searched for a hidden goal location along a line between 2 distinct landmarks on a computer screen. On baseline trials, the location of the landmarks and goal varied, but the distance between each of the landmarks and the goal was held constant, with 1 landmark always closer to the goal. In Experiment 1, some baseline trials provided both landmarks, and some provided only 1 landmark. On probe trials, both landmarks were shifted apart relative to the previously learned goal location. Participants searched between the locations specified by the 2 landmarks and their search locations were shifted more toward the nearer landmark, suggesting a weighted integration of the conflicting landmarks. Moreover, the observed variance in search responses when both cues were presented in their normal locations was reduced compared to the variance on tests with single landmarks. However, the variance reduction and the weightings of the landmarks did not always show Bayesian optimality. In Experiment 2, some participants were trained only with each of the single landmarks. On subsequent tests with the 2 cues in conflict, searching did not shift toward the nearer landmark and the variance of search responses of these single-cue trained participants was larger than their variance on single-landmark tests, and even larger than the variance predicted by using the 2 landmarks alternatively on different trials. Taken together, these results indicate that cue combination occurs only when the landmarks are presented together during the initial learning experience. (PsycINFO Database Record
作者们研究了人类如何利用多个地标来定位目标。参与者在电脑屏幕上沿着两个不同地标之间的一条线寻找隐藏的目标位置。在基线试验中，地标的位置和目标位置各不相同，但每个地标与目标之间的距离保持不变，其中一个地标总是更靠近目标。在实验1中，一些基线试验提供了两个地标，而一些只提供了一个地标。在探测试验中，相对于之前学习到的目标位置，两个地标都被移开了。参与者在两个地标指定的位置之间进行搜索，他们的搜索位置更多地朝着较近的地标移动，这表明存在对相互冲突的地标的加权整合。此外，与单地标测试相比，当两个线索都在其正常位置呈现时，观察到的搜索反应方差减小了。然而，方差减小和地标的加权并不总是表现出贝叶斯最优性。在实验2中，一些参与者仅接受了每个单地标训练。在随后对两个冲突线索的测试中，搜索并没有朝着较近的地标移动，这些单线索训练参与者的搜索反应方差大于他们在单地标测试中的方差，甚至大于在不同试验中交替使用两个地标所预测的方差。综上所述，这些结果表明，只有当地标在初始学习过程中一起呈现时，才会发生线索组合。（PsycINFO数据库记录）
