Hahn Sowon, Andersen George J, Saidpour Asad
University of California at Riverside, USA.
Psychol Sci. 2003 Nov;14(6):543-8. doi: 10.1046/j.0956-7976.2003.psci_1463.x.
In the current study, we explored observers' use of two distinct analyses for determining their direction of motion, or heading: a scene-based analysis and a motion-based analysis. In two experiments, subjects viewed sequentially presented, paired digitized images of real-world scenes and judged the direction of heading; the pairs were presented with various interstimulus intervals (ISIs). In Experiment 1, subjects could determine heading when the two frames were separated with a 1,000-ms ISI, long enough to eliminate apparent motion. In Experiment 2, subjects performed two tasks, a path-of-motion task and a memory-load task, under three different ISIs, 50 ms, 500 ms, and 1,000 ms. Heading accuracy decreased with an increase in ISI. Increasing memory load influenced heading judgments only for the longer ISI when motion-based information was not available. These results are consistent with the hypothesis that the scene-based analysis has a coarse spatial representation, is a sustained temporal process, and is capacity limited, whereas the motion-based analysis has a fine spatial resolution, is a transient temporal process, and is capacity unlimited.
在当前的研究中，我们探究了观察者运用两种不同分析方法来确定其运动方向（即航向）的情况：基于场景的分析和基于运动的分析。在两项实验中，受试者观看按顺序呈现的、成对的真实世界场景数字化图像，并判断航向；这些图像对以不同的刺激间隔（ISI）呈现。在实验1中，当两帧图像以1000毫秒的ISI间隔呈现时，受试者能够确定航向，这个间隔足够长，足以消除似动现象。在实验2中，受试者在三种不同的ISI（50毫秒、500毫秒和1000毫秒）下执行两项任务，即运动路径任务和记忆负荷任务。航向准确性随着ISI的增加而降低。当基于运动 的信息不可用时，增加记忆负荷仅对较长的ISI的航向判断产生影响。这些结果与以下假设一致：基于场景的分析具有粗略的空间表征，是一个持续的时间过程，且容量有限；而基于运动的分析具有精细的空间分辨率，是一个短暂的时间过程，且容量无限。
