Payne D G, Roediger H L
Am J Psychol. 1987 Summer;100(2):145-65.
Two experiments investigated the effect of encoding conditions and type of test (recall vs. recognition) on the phenomenon of hypermnesia (improved performance across repeated tests). Subjects in Experiment 1 studied a list of words using either imaginal or semantic elaboration strategies and then received three successive tests. Different groups of subjects received either free recall, four-alternative forced-choice recognition, or yes/no recognition tests. Reliable hypermnesia was found only in the recall conditions, with the recognition conditions showing either no change in performance levels across tests (forced-choice tests) or significant forgetting (yes/no tests). In Experiment 2, subjects studied a list of words, and encoding was manipulated using three orienting tasks. Once again, hypermnesia was found with the recall tests but not with the forced choice recognition tests. Finding hypermnesia in recall but not in recognition indicates that retrieval processes in recall play a major role in producing hypermnesia. Also, the finding that the magnitude of the recall hypermnesias increased with an increase in total cumulative recall levels across study conditions suggests that cumulative recall levels are an important factor in determining the presence or absence of recall hypermnesia.
两项实验研究了编码条件和测试类型（回忆与识别）对记忆增强现象（重复测试中表现改善）的影响。实验1中的受试者使用意象或语义 elaboration 策略学习一组单词列表，然后接受三次连续测试。不同组的受试者分别接受自由回忆、四选一强制选择识别或是非识别测试。仅在回忆条件下发现了可靠的记忆增强，识别条件下测试中的表现水平要么没有变化（强制选择测试），要么出现显著遗忘（是非测试）。在实验2中，受试者学习一组单词列表，并使用三种定向任务来操纵编码。同样，在回忆测试中发现了记忆增强，但在强制选择识别测试中未发现。在回忆中而非识别中发现记忆增强表明，回忆中的检索过程在产生记忆增强中起主要作用。此外，在不同学习条件下，回忆性记忆增强的幅度随着总累积回忆水平的增加而增加这一发现表明，累积回忆水平是决定是否存在回忆性记忆增强的一个重要因素。
