The testing effect in free recall is associated with enhanced organizational processes

In two experiments with categorized lists, we asked whether the testing effect in free recall is related to enhancements in organizational processing. During a first phase in Experiment 1, subjects studied one list over eight consecutive trials, they studied another list six times while taking two interspersed recall tests, and they learned a third list in four alternating study and test trials. On a test 2 days later, recall was directly related to the number of tests and inversely related to the number of study trials. In addition, increased testing enhanced both the number of categories accessed and the number of items recalled from within those categories. One measure of organization also increased with the number of tests. In a second experiment, different groups of subjects studied a list either once or twice before a final criterial test, or they studied the list once and took an initial recall test before the final test. Prior testing again enhanced recall, relative to studying on the final test a day later, and also improved category clustering. The results suggest that the benefit of testing in free recall learning arises because testing creates retrieval schemas that guide recall.     

Generalizing test-enhanced learning from the laboratory to the classroom

Test-enhanced learning refers to the fact that taking an initial test on studied material enhances its later retention relative to simply studying the material and then taking a final test. Most research on the testing effect has been done with materials such as word lists, and the general finding has been that the benefits of testing are greater when the initial test is a recall (production) test rather than a recognition test. We briefly summarize three experiments that extend these results to educationally relevant materials, namely brief articles, lectures, and materials in a college course. All three experiments demonstrated a robust testing effect and also revealed that an initial short-answer test produced greater gains on a final test than did an initial multiple-choice test. Furthermore, one experiment revealed a positive effect of immediate feedback given with the initial test. The educational implications are that production tests (short answer or essay) and feedback soon after learning increase learning and retention. In addition, frequent testing probably has the indirect positive effects of keeping students motivated and leading them to space out periods of study.     

Does the testing effect depend on presentation modality?

We examined whether the testing effect generalizes to an auditory presentation modality. Five lists of unrelated words (Experiment 1) and related words (Experiment 2) were presented to participants, half of whom studied them visually and half studied them auditorily. Participants in the study-only condition performed a short distractor task following lists 1–4, whereas those in the testing condition completed a short distractor task and then attempted to recall each list. Both groups were subsequently tested on List 5 and on all five lists 30 min later. In both experiments, we found a testing effect for both List 5 and for the final cumulative recall test. However, the effect did not interact with study modality, despite the fact that proactive interference was greater following auditory study. These results have important implications for educational practice, suggesting that initial testing is important for materials presented in auditory as well as visual formats.     

The role of retrieval mode and retrieval orientation in retrieval practice: insights from comparing recognition memory testing formats and restudying

The effectiveness of retrieval practice for aiding long-term memory, referred to as the testing effect, has been widely demonstrated. However, the specific neurocognitive mechanisms underlying this phenomenon remain unclear. In the present study, we sought to explore the role of pre-retrieval processes at initial testing on later recognition performance by using event-related potentials (ERPs). Subjects studied two lists of words (Chinese characters) and then performed a recognition task or a source memory task, or restudied the word lists. At the end of the experiment, subjects received a final recognition test based on the remember–know paradigm. Behaviorally, initial testing (active retrieval) enhanced memory retention relative to restudying (passive retrieval). The retrieval mode at initial testing was indexed by more positive-going ERPs for unstudied items in the active-retrieval tasks than in passive retrieval from 300 to 900 ms. Follow-up analyses showed that the magnitude of the early ERP retrieval mode effect (300–500 ms) was predictive of the behavioral testing effect later on. In addition, the ERPs for correctly rejected new items during initial testing differed between the two active-retrieval tasks from 500 to 900 ms, and this ERP retrieval orientation effect predicted differential behavioral testing gains between the two active-retrieval conditions. Our findings confirm that initial testing promotes later retrieval relative to restudying, and they further suggest that adopting pre-retrieval processing in the forms of retrieval mode and retrieval orientation might contribute to these memory enhancements.     

Paradoxical effects of testing: Repeated retrieval attempts enhance the likelihood of later accurate and false recall

The testing effect is the finding that taking an initial test enhances the likelihood of later recall. The present report examines the extent to which this benefit of testing comes with a cost: an enhanced likelihood of erroneously recalling incorrect information. Subjects were given short lists of semantic associates (e.g., hill, valley, climb); each list converged upon a related nonpresented word (e.g., mountain). After presentation of some lists, the subjects received no initial test; after others, one initial free recall test; and after others, three successive free recall tests. The probabilities of final free recall (and the probability of reporting vivid recollection of the moment of encoding) of both studied and related, nonstudied words (e.g., mountain) were highest when three initial tests had been taken, intermediate following one initial test, and lowest when no initial test had occurred. The beneficial effects of testing carry the cost of increases in erroneous memory for related information.     

A short-term testing effect in cross-language recognition

Taking a memory test after an initial study phase produces better long-term retention than restudying the items, a phenomenon known as the testing effect. We propose that this effect emerges because testing strengthens semantic features of items' memory traces, whereas restudying strengthens surface features of items' memory traces. This novel account predicts that a testing effect should be observed even after a short retention interval when a language switch occurs between the learning phase and the final test phase. We assessed this prediction with Dutch-English bilinguals who learned Dutch Deese-Roediger-McDermott word lists through restudying or through testing (retrieval practice). Five minutes after this learning phase, they took a recognition test in Dutch (within-language condition) or in English (across-language condition). We observed a testing effect in the across-language condition, but not in the within-language condition. These findings corroborate our novel account of the testing effect.     

记忆的前向测试效应对老年人学习新事物的作用

为检验前置测试是否可以有效地提升老年人学习新事物的能力,参与实验的老年人被随机分为有前置测试的实验组和无前置测试的对照组,在实验1中学习了5列单词,在实验2中记忆了5列日用品,在实验3中学习了4段讲座视频。结果表明,实验组老年人对新事物的记忆成绩均高于对照组的老年人。结论认为,前置测试能够显著提升老年人学习新事物的能力,干扰降低与学习参与相结合的“加减”理论能更好地解释提升老年人记忆的前向测试效应。     

Tests enhance retention and transfer of spatial learning

Many studies have reported that tests are beneficial for learning (e.g., Roediger & Karpicke, 2006a). However, the majority of studies on the testing effect have been limited to a combination of relatively simple verbal tasks and final tests that assessed memory for the same material that had originally been tested. The present study explored whether testing is beneficial for complex spatial memory and whether these benefits hold for both retention and transfer. After encoding a three-dimensional layout of objects presented in a virtual environment, participants completed a judgment-of-relative-direction (JRD) task in which they imagined standing at one object, facing a second object, and pointed to a third object from the imagined perspective. Some participants completed this task by relying on memory for the previously encoded layout (i.e., the test conditions), whereas for others the location of the third object was identified ahead of time, so that retrieval was not required (i.e., the study condition). On a final test assessing their JRD performance, the participants who learned through test outperformed those who learned through study. This was true even when corrective feedback was not provided on the initial JRD task and when the final test assessed memory from vantage points that had never been practiced during the initial JRD.     

Reducing the Misinformation Effect Through Initial Testing: Take Two Tests and Recall Me in the Morning?

Initial retrieval of an event can reduce people's susceptibility to misinformation. We explored whether protective effects of initial testing could be obtained on final free recall and source‐monitoring tests. After studying six household scenes (e.g., a bathroom), participants attempted to recall items from the scenes zero, one, or two times. Immediately or after a 48‐hour delay, non‐presented items (e.g., soap and toothbrush) were exposed zero, one, or four times through a social contagion manipulation in which participants reviewed sets of recall tests ostensibly provided by other participants. A protective effect of testing emerged on a final free recall test following the delay and on a final source‐memory test regardless of delay. Taking two initial tests did not increase these protective effects. Determining whether initial testing will have protective (versus harmful) effects on memory has important practical implications for interviewing eyewitnesses. © 2015 The Authors. Applied Cognitive Psychology published by John Wiley & Sons, Ltd.     

“P300” and memory: Individual differences in the von Restorff effect

Event-related brain potentials (ERPs) were elicited by words in a free recall paradigm that included a novel item. The P300 component of the ERP is elicited by novel, task-relevant events, and we tested the hypothesis that P300 is a manifestation of the cognitive processing invoked during “context updating.” If the degree to which current representations in working memory need revision is related to P300 amplitude, then the P300 elicited by a given item should be related to the ability to recall that item on a subsequent test. Forty lists were presented to 12 subjects in each of two sessions. The lists were 15 words long, and 1 word, in position 6 through 10, was “isolated” by changing its size. Most subjects recalled these isolated words more often than other words in the same positions (von Restorff effect), and these words also elicited larger P300s than other words. Analysis of variance on the component scores from a principal components analysis revealed that words recalled had a larger amplitude P300 (on initial presentation) than words not recalled. Striking individual differences emerged, and there were strong relationships between the von Restorff effect, overall recall performance, mnemonic strategies, and the association between components of the ERP and recall performance. The overall recall performance of subjects who reported simple (rote) mnemonic strategies was low, but they showed a high von Restorff effect. For these subjects the amplitude of the P300 elicited by words during initial presentation predicted later recall. In contrast, subjects who reported complex mnemonic strategies remembered a high percentage of words and did not show a von Restorff effect. For these subjects P300 did not predict later recall, although a later “slow wave” component of the ERP did. The initial response to isolated items was the same for all subjects (a large P300), and all subjects recognized the isolates faster than other words in a recognition test given at the end of each session. The subjects in whom P300 did not predict recall reported mnemonic strategies that involved organizing the material. These strategies continue long after the time period reflected by P300 (600 msec). Because they were so effective they may have overshadowed the relationship between P300 and recall, which is based on the initial encoding of an event. Our interpretations were further confirmed and clarified from data obtained in a final grand recall and in the recognition test.     

Total retrieval time and hypermnesia: Investigating the benefits of multiple recall tests

Hypermnesia is an increase in recall over repeated tests. A core issue is the role of repeated testing, per se, versus total retrieval time. Prior research implies an equivalence between multiple recall tests and a single test of equal total duration, but theoretical analyses indicate otherwise. Three experiments investigated this issue using various study materials (unrelated word lists, related word lists, and a short story). In the first experimental session, the study phase was followed by a series of short recall tests or by a single, long test of equal total duration. Two days later, participants took a final recall test. The multiple and single test conditions produced equivalent performance in the first session, but the multiple test group exhibited less forgetting and fewer item losses in the final test. In a fourth experiment, using a brief delay (15 min) between the recall sessions, the multiple recall condition produced greater hypermnesia as well as fewer item losses. In addition, final recall was significantly higher in the multiple than in the single test condition in three of the four experiments. Thus, single and repeated recall tests of equal total duration are not functionally equivalent, but rather produce differences observable in subsequent recall tests.     

Evaluating the contributions of task expectancy in the testing and guessing benefits on recognition memory

Recently, we have shown that two types of initial testing (recall of a list or guessing of critical items repeated over 12 study/test cycles) improved final recognition of related and unrelated word lists relative to restudy. These benefits were eliminated, however, when test instructions were manipulated within subjects and presented after study of each list, procedures designed to minimise expectancy of a specific type of upcoming test [Huff, Balota, & Hutchison, 2016. The costs and benefits of testing and guessing on recognition memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 42, 1559–1572. doi:10.1037/xlm0000269], suggesting that testing and guessing effects may be influenced by encoding strategies specific for the type of upcoming task. We follow-up these experiments by examining test-expectancy processes in guessing and testing. Testing and guessing benefits over restudy were not found when test instructions were presented either after (Experiment 1) or before (Experiment 2) a single study/task cycle was completed, nor were benefits found when instructions were presented before study/task cycles and the task was repeated three times (Experiment 3). Testing and guessing benefits emerged only when instructions were presented before a study/task cycle and the task was repeated six times (Experiments 4A and 4B). These experiments demonstrate that initial testing and guessing can produce memory benefits in recognition, but only following substantial task repetitions which likely promote task-expectancy processes.     

The effect of forced recall on illusory recollection in younger and older adults

The effect of an initial forced recall test on later recall and recognition tests was examined in younger and older adults. Subjects were presented with categorized word lists and given an initial test under standard cued recall instructions (with a warning against guessing) or forced recall instructions (that required guessing); subjects were later given a cued recall test for the original list items. In 2 experiments, initial forced recall resulted in higher levels of illusory memories on subsequent tests (relative to initial cued recall), especially for older adults. Older adults were more likely to say they remembered rather than knew that forced guesses had occurred in the original study episode. The effect persisted despite a strong warning against making errors in Experiment 2. When a source monitoring test was given, older adults had more difficulty than younger adults in identifying the source of items they had originally produced as guesses. If conditions encourage subjects to guess on a first memory test, they are likely to recollect these guesses as actual memories on later tests. This effect is exaggerated in older adults, probably because of their greater source monitoring difficulties. Both dual process and source monitoring theories provide insight into these findings.     

Testing effects for common versus proper names

The present study examines the testing effect as a function of item meaningfulness. In Experiments 1 and 2 participants studied lists of words that could serve as proper names or occupations (e.g., Mr Baker or baker), with the items given in a name context for one group and an occupation context for a second group. During an intervening phase participants restudied some items and were given a cued recall test (Experiment 1) or a free recall test (Experiment 2) on other items. On a final free recall test memory was better for tested items than studied items in both the name and occupation contexts. Experiment 3 followed the same procedure as Experiment 1, except that participants studied lists of proper names that do not have alternative uses in the English language (e.g., Mr Anderson) or studied concrete nouns (e.g., letter). Tested items were better remembered on a final test than studied items, and there was no interaction with type of study material. These results show that the testing effect extends to proper names, material that is commonly assumed to differ from common names on several dimensions.     

When does feedback facilitate learning of words?

Some researchers have suggested that although feedback may enhance performance during associative learning, it does so at the expense of later retention. To examine this issue, subjects (N = 258) learned Luganda-English word pairs. After 2 initial exposures to the materials, subjects were tested on each item several times, with the presence and type of feedback varying between subjects. A final test followed after 1 week. Supplying the correct answer after an incorrect response not only improved performance during the initial learning session--it also increased final retention by 494%. On the other hand, feedback after correct responses made little difference either immediately or at a delay, regardless of whether the subject was confident in the response. Practical and theoretical implications are discussed.     

Testing effects in mixed- versus pure-list designs

In the present study, we investigated the role of list composition in the testing effect. Across three experiments, participants learned items through study and initial testing or study and restudy. List composition was manipulated, such that tested and restudied items appeared either intermixed in the same lists (mixed lists) or in separate lists (pure lists). In Experiment 1, half of the participants received mixed lists and half received pure lists. In Experiment 2, all participants were given both mixed and pure lists. Experiment 3 followed Erlebacher’s (Psychological Bulletin, 84, 212–219, 1977) method, such that mixed lists, pure tested lists, and pure restudied lists were given to independent groups. Across all three experiments, the final recall results revealed significant testing effects for both mixed and pure lists, with no reliable difference in the magnitude of the testing advantage across list designs. This finding suggests that the testing effect is not subject to a key boundary condition—list design—that impacts other memory phenomena, including the generation effect.     

Does response mode affect amount recalled or the magnitude of the testing effect?

The testing effect is the finding that retrieval practice can enhance recall on future tests. One unanswered question is whether first-test response mode (writing or speaking the answer) affects final-test performance (and whether final-test response mode itself matters). An additional unsettled issue is whether written and oral recall lead to differences in the amount recalled. In three experiments, we examined these issues: whether subjects can recall more via typing or speaking; whether typing or speaking answers on a first test can lead to better final-test performance (and whether an interaction occurs with final-test response mode) and whether any form of overt response leads to better final-test performance as compared to covert retrieval (thinking of the answer but not producing it). Subjects studied paired associates; took a first test by typing, speaking, or thinking about responses; and then took a second test in which the answers were either spoken or typed. The results revealed few differences between typing and speaking during recall, and no difference in the size of the testing effect on the second test. Furthermore, an initial covert retrieval yielded roughly the same benefit to future test performance as did overt retrieval. Thus, the testing effect was quite robust across these manipulations. The practical implication for learning is that covert retrieval provides as much benefit to later retention as does overt retrieval and that both can be effective study strategies.     

Illusory recollection of voices

We investigated source misattributions in the DRM false memory paradigm (Deese, 1959, Roediger & McDermott, 1995). Subjects studied words in one of two voices, manipulated between-lists (pure-voice lists) or within-list (mixed-voice lists), and were subsequently given a recognition test with voice-attribution judgements. Experiments 1 and 2 used visual tests. With pure-voice lists (Experiment 1), subjects frequently attributed related lures to the corresponding study voice, despite having the option to not respond. Further, these erroneous attributions remained high with mixed-voice lists (Experiment 2). Thus, even when their related lists were not associated with a particular voice, subjects misattributed the lures to one of the voices. Attributions for studied items were fairly accurate in both cases. Experiments 3 and 4 used auditory tests. With pure-voice lists (Experiment 3), subjects frequently attributed related lures and studied items to the corresponding study voice, regardless of the test voice. In contrast, with mixed-voice lists (Experiment 4), subjects frequently attributed related lures and studied items to the corresponding test voice, regardless of the study voice. These findings indicate that source attributions can be sensitive to voice information provided either at study or at test, even though this information is irrelevant for related lures.     

Retrieval practice can eliminate list method directed forgetting

It has recently been shown that retrieval practice can reduce memories’ susceptibility to interference, like retroactive and proactive interference. In this study, we therefore examined whether retrieval practice can also reduce list method directed forgetting, a form of intentional forgetting that presupposes interference. In each of two experiments, subjects successively studied two lists of items. After studying each single list, subjects restudied the list items to enhance learning, or they were asked to recall the items. Following restudy or retrieval practice of list 1 items, subjects were cued to either forget the list or remember it for an upcoming final test. Experiment 1 employed a free-recall and Experiment 1 a cued-recall procedure on the final memory test. In both experiments, directed forgetting was present in the restudy condition but was absent in the retrieval-practice condition, indicating that retrieval practice can reduce or even eliminate this form of forgetting. The results are consistent with the view that retrieval practice enhances list segregation processes. Such processes may reduce interference between lists and thus reduce directed forgetting.     

Illusory recollection of voices

We investigated source misattributions in the DRM false memory paradigm (Deese, 1959, Roediger & McDermott, 1995). Subjects studied words in one of two voices, manipulated between‐lists (pure‐voice lists) or within‐list (mixed‐voice lists), and were subsequently given a recognition test with voice‐attribution judgements. Experiments 1 and 2 used visual tests. With pure‐voice lists (Experiment 1), subjects frequently attributed related lures to the corresponding study voice, despite having the option to not respond. Further, these erroneous attributions remained high with mixed‐voice lists (Experiment 2). Thus, even when their related lists were not associated with a particular voice, subjects misattributed the lures to one of the voices. Attributions for studied items were fairly accurate in both cases. Experiments 3 and 4 used auditory tests. With pure‐voice lists (Experiment 3), subjects frequently attributed related lures and studied items to the corresponding study voice, regardless of the test voice. In contrast, with mixed‐voice lists (Experiment 4), subjects frequently attributed related lures and studied items to the corresponding test voice, regardless of the study voice. These findings indicate that source attributions can be sensitive to voice information provided either at study or at test, even though this information is irrelevant for related lures.