Mewhort D J, Johns E E, Coble S
Department of Psychology, Queen's University, Kingston, Ontario, Canada.
Percept Psychophys. 1991 Sep;50(3):258-66. doi: 10.3758/bf03206749.
In studies of iconic memory using the bar-probe task, subjects see a brief display of target letters and are probed by an arrow to report one of them. According to the classic early-selection account, subjects use the probe to select material for perceptual analysis from a precategorical (iconic) memory, but according to late-selection theories, subjects first identify the letters and then use the probe to select one letter for report from the set of categorized items. Pashler (1984) based his test for the locus of selection on a manipulation of display quality in previewed displays. He presented a target for 200 msec and then added a probe, together with the target, for an additional 150 msec. Reducing the target's stimulus quality increased response latency. If the subjects identified the characters before the probe appeared and then selected an item for report, the clarity of the original array should not have affected response latency. Hence, Pashler concluded that his subjects used the probe to select from a precategorical store (early selection). Pashler's experiment did not force subjects to rely on memory of the target; hence, although his experiment documented a situation in which subjects used early selection, it did not rule out late selection in studies of information persistence. We replicated Pashler's findings and, using his logic, showed that when subjects are forced to rely on memory of the target, they select from a categorized store.
在使用条形探针任务进行的图像记忆研究中，受试者会短暂看到一组目标字母，然后会出现一个箭头提示他们报告其中一个字母。根据经典的早期选择理论，受试者使用提示从预分类（图像）记忆中选择用于感知分析的材料，但根据晚期选择理论，受试者首先识别字母，然后使用提示从已分类项目集合中选择一个字母进行报告。帕施勒（1984年）基于对预视显示中显示质量的操控来测试选择的位点。他先呈现一个目标200毫秒，然后在呈现目标的同时再增加一个提示，持续额外的150毫秒。降低目标的刺激质量会增加反应潜伏期。如果受试者在提示出现之前就识别了字符，然后选择一个项目进行报告，那么原始阵列的清晰度就不应该影响反应潜伏期。因此，帕施勒得出结论，他的受试者是使用提示从预分类存储中进行选择（早期选择）。帕施勒的实验并没有迫使受试者依赖对目标的记忆；因此，尽管他的实验记录了受试者使用早期选择的情况，但在信息持续性研究中并没有排除晚期选择。我们重复了帕施勒的研究结果，并运用他的逻辑表明，当受试者被迫依赖对目标的记忆时，他们是从已分类存储中进行选择。
