Abstract: Time perception has been shown to be influenced by the attentional guidance from working memory (WM)，with that the stimulus matching the working memory content was judged to last longer than mismatching stimulus. However, the guidance effect might be flexible and modulated by other factors. In this study, we combined change detection task paradigm and time comparison task to exam the influence of ISI (the stimulusinterval between the offset of WM content and the onset of target duration) and target duration on time judgment. Participants were asked to memorize an abstract object (both the color and shape) for a subsequent memory test in which they indicated whether a test object changed. During the delay period, participants had to judge which one of two successive objects was presented longer (or shorter), with one object matched the WM item while the other did not. Mere observation without WM demand was taken as control task to exclude the contribution of repetition. The results showed that when the ISI was short (Experiment 1), time judgment accuracy was greater on memory-matching trials relative to memory-mismatching trials, suggesting the memory-matching stimuli facilitated time perception. However, when the ISI was longer (Experiment 2), the guidance effect declined. On the other hand, irrelevant of short ISI or long ISI, WM task or mere repetition, when the duration to be perceived was longer, matching stimuli inversely decreased perceived time. This study suggests that the effect of visual working memory on time judgment is flexible, and is modulated by the interstimulus interval as well as the target duration to be perceived. The variability of object working memory on timing task might be related to the focus and allocation of attention.

Key words: working memory, retention time, time perception, attention orientation

摘要： 本研究操作记忆信息与计时开始之间的时间间隔（ISI）和目标时距，探讨工作记忆影响时间判断的灵活性。被试首先记忆一个客体，然后在每个trial的最后判断测试刺激是否与记忆项相同；在延迟阶段，被试完成时间判断任务，即判断相继出现的两个刺激的时距哪个更长（或更短）。时间任务中的一个刺激与记忆内容完全相同，相应的另一个刺激与记忆内容在形状和颜色上都不同。重复条件下，被试忽略第一个刺激，仅完成时间判断任务。结果发现，时间间隔（ISI）短时，记忆匹配条件下的准确率更高，匹配刺激延长了知觉的时间；但随着时间间隔的增加，工作记忆匹配对时间判断的影响降低甚至消失。并且，长或短ISI，记忆任务或重复条件下，目标时距长时，记忆匹配反而缩短了知觉的时间。研究说明工作记忆对时间判断的影响是灵活的，受到注意或工作记忆等高级认知系统的调控。

关键词: 工作记忆, 保持时间, 时间知觉, 注意定向