Retrieval potentiates new learning: A theoretical and meta-analytic review

Guessing as a learning intervention: A meta-analytic review of the prequestion effect

Giving students test questions before they have learned the correct answers (i.e., prequestions) enhances learning. However, existing research has provided conflicting evidence on whether the benefits of prequestions are specific to the initially tested material or if they generalize to new, nontested material. In this review, we summarize the literature on the prequestion effect, describe the attention-based account underlying this effect, report a meta-analysis of the magnitude of the specific and general effects, and explore theoretically and empirically relevant moderator variables that influence the size and direction of the prequestion effect. This preregistered meta-analysis demonstrated a moderate specific effect (g = 0.54, k = 97) but a virtually nonexistent general effect (g = 0.04, k = 91). Overall, the attention-based account received support from some theoretically relevant moderator analyses. Future researchers are encouraged to conduct theoretically motivated studies to help clarify the mechanisms that underlie the attention-enhancing effects of prequestions and to explore the benefits of prequestions in educational domains to establish the extent to which these effects translate into the classroom.

The role of mediators for the pretesting effect

Taking a pretest (e.g., smoke - ?) before material is studied (smoke - fog) can improve later recall of that material, compared to material which was initially only studied. The goal of the present study was to evaluate for this pretesting effect the potential role of semantic mediators, i.e., of unstudied information that is semantically related to the study material. In all three experiments, subjects studied weakly associated word pairs (e.g., smoke - fog), half of which received a pretest. Subjects then either completed a recognition test (Experiment 1) or a cued-recall test (Experiments 2 and 3), during which they were presented with both the original study material and never-before-seen semantic mediators that were strongly related to the cue item of a pair (e.g., cigarette). Strikingly, presenting semantic mediators as lures led to higher false alarm rates for mediators following initial pretesting than study only (Experiment 1), and presenting semantic mediators as retrieval cues led to better recall of target items following pretesting than study only (Experiments 2 and 3). We argue that these findings support the elaboration account of the pretesting effect but are difficult to reconcile with other prominent accounts of the effect.

Self-relevance enhances susceptibility to false memory

Eyewitness testimony serves as important evidence in the legal system. Eyewitnesses of a crime can be either the victims themselves-for whom the experience is highly self-referential-or can be bystanders who witness and thus encode the crime in relation to others. There is a gap in past research investigating whether processing information in relation to oneself versus others would later impact people's suggestibility to misleading information. In two experiments (Ns = 68 and 122) with Dutch and Chinese samples, we assessed whether self-reference of a crime event (i.e., victim vs. bystander) affected their susceptibility to false memory creation. Using a misinformation procedure, we photoshopped half of the participants' photographs into a crime slideshow so that they saw themselves as victims of a nonviolent crime, while others watched the slideshow as mock bystander witnesses. In both experiments, participants displayed a self-enhanced suggestibility effect: Participants who viewed themselves as victims created more false memories after receiving misinformation than those who witnessed the same crime as bystanders. These findings suggest that self-reference might constitute a hitherto new risk factor in the formation of false memories when evaluating eyewitness memory reports.

Interpolated retrieval retroactively increases recall and promotes cross-episode memory interdependence

Retrieving existing memories before new learning can lead to retroactive facilitation. Three experiments examined whether interpolated retrieval is associated with retroactive facilitation and memory interdependence that reflects integrative encoding. Participants studied two lists of cue-response word pairs that repeated across lists (A-B, A-B), appeared in list 1 (A-B, -), or included the same cues with changed responses in each list (A-B, A-C). For A-B, A-C pairs, the tasks interpolated between lists required recall of list 1 (B) responses (with or without feedback) or restudy of complete list 1 (A-B) pairs. In list 2, participants only studied pairs (experiment 1) or studied pairs, attempted to detect changed (C) responses, and attempted to recall list 1 responses for detected changes (experiments 2 and 3). On a final cued recall test, participants attempted to recall list 1 responses, indicated whether responses changed between lists, and if so, attempted to recall list 2 responses. Interpolated retrieval was associated with subsequent retroactive facilitation and greater memory interdependence for B and C responses. These correlational findings are compatible with the view that retrieval retroactively facilitates memories, promotes coactivation of existing memories and new learning, and enables integrative encoding that veridically binds information across episodes.

The pretesting effect thrives in the presence of competing information

Taking a pretest (e.g., blanket - ?) before some target material (blanket - sheet) is studied can promote recall of that material on a subsequent final test compared to material which was initially only studied. Here, we examine whether such pretesting can shield the tested material from interference-induced forgetting, which often occurs when before final testing, related material is encountered. We applied a typical pretesting task but asked subjects, between acquisition and final testing of the target list (list 1), to study two additional lists of items with either completely new and unique pairs (e.g., atom - cell) or overlapping - and thus potentially interfering - pairs (e.g., blanket - sleep). Target-list recall on the final test showed a typical pretesting effect for unique pairs, but the size of the effect even increased for overlapping pairs, as recall of study-only pairs was impaired, whereas recall of pretest pairs was left largely unaffected. This held regardless of whether a low (Experiment 1) or high (Experiment 2) degree of learning was induced for the interfering material, suggesting that pretesting can indeed protect the tested material from interference. These findings indicate that pretesting could play a significant role in educational settings where information often needs to be retained in the presence of competing information.

Updating and pre-existing semantic associations: testing can enhance or impair new learning

We often need to update what we have learned, building on older information by adding newer information. When updating, is it better to review the older information by retrieving it (testing) or restudying it? In other words, do tests result in enhanced updating or impaired updating compared to restudying? Past research has obtained divergent conclusions to this question. The present study used a paired associates updating paradigm in which participants studied a cue and the older response (A-B). They later reviewed the older response by restudying (A-B) or testing (A-?; A-B) and immediately after learned a newer response (-D) that updated the original pair into a trio (A-B-D). In eight experiments, we demonstrated that different patterns of pre-existing semantic associations between the cue, older response, and newer response resulted in all possible outcomes: test enhanced new learning, test impaired new learning, and no difference. The results were most consistent with a family of updating theories that propose the metacognitive processes that occur after reviewing determine whether testing enhances, impairs, or has no impact on new learning. The results suggest that theories should consider the impact of the newer response in updating in addition to performance on the initial test.

Guessing can benefit memory for related word pairs even when feedback is delayed

Trying to guess what the correct answer to a question might be can facilitate future learning of this answer when presented in the form of corrective feedback. One issue that determines the effectiveness of guessing as a learning strategy is the timing of the presentation of feedback: it can be presented either immediately after the guess, or after a delay. Whereas the timing of feedback is of little importance for complex materials such as trivia questions, previous research suggests that for simpler materials such as related word pairs guessing seems to benefit learning only when feedback is immediate. In order to test whether this always has to be the case, we conducted two experiments in which we increased the richness of study materials by superimposing the to-be-learned word pairs over unrelated context pictures. We then manipulated the match between contexts at study and at test (Experiment 1) and at the time of feedback delivery (Experiment 2). Contrary to previous studies showing no benefits of guessing with delayed feedback, our results show that learning related word pairs can benefit from guessing even when feedback is delayed. These benefits of guessing occur if participants are reminded via reinstated contexts of the guessing stage at the time of feedback delivery. Our results help constrain theories of guessing benefits and extend theories of reminding.

How retrieval practice and semantic generation affect subsequently studied material: an analysis of item-level effects

The forward testing effect (FTE) refers to the finding that retrieval practice of previously studied material can facilitate recall of newly studied (critical) material. Such interim retrieval practice can also lead to a differential FTE, i.e., a more pronounced FTE for items at early than later serial positions in the critical material. The present study examined whether this differential FTE also holds with interim semantic generation of extra-list items, and whether it is influenced by study material. Consistent with prior work, the results of two experiments showed that both interim retrieval practice and interim semantic generation induce the general (list-level) FTE when unrelated study lists are applied, whereas retrieval practice only creates the effect with categorised study lists. Critically, however, the differential FTE was present in response to retrieval practice but absent in response to semantic generation. This pattern held regardless of which material was studied, thus experimentally dissociating the general (list-level) from the differential (item-level) FTE. The findings may suggest that retrieval practice, but not semantic generation, induces a reset of the encoding process which promotes attentional encoding such that a more pronounced FTE arises for early than middle and late serial positions in the critical list.

Students Can (Mostly) Recognize Effective Learning, So Why Do They Not Do It?

Cognitive psychology research has emphasized that the strategies that are effective and efficient for fostering long-term retention (e.g., interleaved study, retrieval practice) are often not recognized as effective by students and are infrequently used. In the present studies, we use a mixed-methods approach and challenge the rhetoric that students are entirely unaware of effective learning strategies. We show that whether being asked to describe strategies used by poor-, average-, and high-performing students (Study 1) or being asked to judge vignettes of students using different strategies (Study 2), participants are generally readily able to identify effective strategies: they were able to recognize the efficacy of explanation, pretesting, interpolated retrieval practice, and even some interleaving. Despite their knowledge of these effective strategies, they were still unlikely to report using these strategies themselves. In Studies 2 and 3, we also explore the reasons why students might not use the strategies that they know are effective. Our findings suggest that interventions to improve learners' strategy use might focus less on teaching them about what is effective and more on increasing self-efficacy, reducing the perceived costs, and establishing better habits.

The Effects of Interspersed Retrieval Practice in Multiple-List Learning on Initially Studied Material

The forward testing effect (FTE) refers to the finding that retrieval practice of previously studied material can facilitate retention of newly studied material more than does restudy of the material. The goal of the present study was to examine how such retrieval practice affects initially studied, unpracticed material. To this end, we used two commonly applied versions of the FTE task, consisting of either three (Experiment 1) or five (Experiment 2) study lists. While study of list 1 was always followed by an unrelated distractor activity, study of list 2 (3-list version) or lists 2, 3, and 4 (5-list version) was followed by either interim restudy or retrieval practice of the immediately preceding list. After studying all lists, participants were either asked to recall the first or last study list. Results showed that, for both the three-list and five-list versions, interim retrieval practice led to a typical FTE, irrespective of whether unrelated or categorized study lists were used. Going beyond the prior work, interim retrieval practice was found to have no effect on initially studied, unpracticed material, regardless of the type of study material. The findings suggest that using interim retrieval practice as a study method can improve recall of the last studied list without incurring a cost for the initially studied material. Our results are difficult to align with the view that retrieval practice induces context change, but are consistent with the idea that retrieval practice can lead participants to employ superior encoding strategies.

Interpolated testing and content pretesting as interventions to reduce task-unrelated thoughts during a video lecture

Considerable research has examined the prevalence and apparent consequences of task-unrelated thoughts (TUTs) in both laboratory and authentic educational settings. Few studies, however, have explored methods to reduce TUTs during learning; those few studies tested small samples or used unvalidated TUT assessments. The present experimental study attempted to conceptually replicate or extend previous findings of interpolated testing and pretesting effects on TUT and learning. In a study of 195 U.S. undergraduates, we investigated whether interpolated testing (compared to interpolated restudy) and pretesting on lecture-relevant materials (compared to pretesting on conceptually related but lecture-irrelevant materials) would reduce TUTs during a video lecture on introductory statistics. Subjects completed either a content-matched or content-mismatched pretest on statistics concepts and then watched a narrated lecture slideshow. During the lecture, half of the sample completed interpolated tests on the lecture material and half completed interpolated restudy of that material. All subjects responded to unpredictably presented thought probes during the video to assess their immediately preceding thoughts, including TUTs. Following the lecture, students reported on their situational interest elicited by the lecture and then completed a posttest. Interpolated testing significantly reduced TUT rates during the lecture compared to restudying, conceptually replicating previous findings—but with a small effect size and no supporting Bayes-factor evidence. We found statistical evidence for neither an interpolated testing effect on learning, nor an effect of matched-content pretesting on TUT rates or learning. Interpolated testing might have limited utility to support students’ attention, but varying effect sizes across studies warrants further work.

Does testing enhance new learning because it insulates against proactive interference?

Taking a test on previously learned material can enhance new learning. One explanation for this forward testing effect is that retrieval inoculates learners from proactive interference (PI). Although this release-from-PI account has received considerable empirical support, most extant evidence is correlational rather than causal. We tested this account by manipulating the level of PI that participants experience as they studied several lists while receiving interpolated tests or not. In Experiments 1 and 2, we found that testing benefited new learning similarly regardless of PI level. These results contradict those from Nunes and Weinstein (Memory, 20(2), 138-154, 2012), who found no forward testing effect when encoding conditions minimized PI. In Experiments 3 and 4, we failed to replicate their results. Together, our data indicate that reduced PI might be a byproduct, rather than a causal factor, of the forward testing effect.

You won't guess that: On the limited benefits of guessing when learning a foreign language

Guessing the meaning of a foreign word before being presented with the right answer benefits recognition performance for the translation compared to reading the full translation outright. However, guessing does not increase memory for the foreign-word-to-translation associations, which is crucial for language acquisition. In this study, we aimed to investigate whether this disadvantage of guessing for performance in cued-recall tests would be eliminated if a restudy phase was added. In Experiments 1–3, we consistently demonstrated that guessing resulted in lower cued-recall performance compared to reading, both before and after restudy. Even for items for which participants successfully recalled their initial guesses on the cued-recall test, accuracy levels did not exceed those from the reading condition. In Experiment 4, we aimed to generalize our findings concerning restudy to a different set of materials – weakly associated word pairs. Even though this time guessing led to better performance than reading, consistent with previous studies, this guessing benefit was not moderated by adding a restudy phase. Our results thus underscore the importance of the initial learning phase for future learning and retention, while undermining the usefulness of the learning-through-guessing strategy for acquiring foreign language vocabulary.

Older and younger adults' revision of health misconceptions

Although ample younger adult research has detailed effective strategies for revising misconceptions, research with older adults is less extensive. Older adults may be less able to correct errors in knowledge due to age-related changes in cognition, but it is also possible that older adults' revision of misconceptions has been limited by methodologies which do not provide adequate support for correction. In two experiments, we examined how older and younger adults revise health-related misconceptions when provided with cognitive support in the form of explicit detailed feedback and an immediate test. Older and younger adults in Experiment 1 answered true/false health statements, received feedback with a detailed explanation of the correct response, took an additional test on the same statements immediately following the initial test, and completed a final test 1-week later. Older and younger adults corrected a similar proportion of misconceptions immediately and maintained most of those revisions across a 1-week delay. In Experiment 2, older adults corrected the same proportion of misconceptions on the final test regardless of whether or not they received a test immediately following feedback. Overall, older adults revised health misconceptions as effectively as did younger adults but variables influencing correction (e.g., belief in feedback) may differ.

Learning new words: Memory reactivation as a mechanism for strengthening and updating a novel word's meaning

In the present study we explored the postlearning changes in a novel word's definition using a cue-induced memory reactivation. Native speakers of Spanish (N = 373) learned low-frequency words with their corresponding definitions. The following day, reactivated groups were exposed to a reminder and provided a subjective assessment of reactivation for each word, while control groups did not receive a reactivation. Study A demonstrated that memory reactivation enhances both explicit recall and semantic integration of new meanings. Study B investigated the effect of memory reactivation in the modification of the new meanings, through three different experiments. Results show an improvement of the updated definitions according to each word's reactivation strength. In addition, congruence with previous knowledge was suggested to be a boundary condition, while consolidation time had a positive modulatory effect. Our findings call attention to reactivation as a factor allowing for malleability as well as persistence of long-term memories for words.

A little can go a long way: giving learners some context can enhance the benefits of pretesting

Tests given to learners before they study new information can enhance the learning of that information. When responding to these pretests, learners typically generate answers that are incorrect but that are nevertheless helpful for improving the learning of the correct answers. The present research examined how providing learners with context prior to pretesting can enhance the benefits of pretesting. Across two experiments, participants were given a pretest for half of the to-be-learned information and then asked to read a passage about a fictional topic, an alien civilisation known as Yoffas (Experiment 1 and Experiment 2), or a unique fruit called the Anona (Experiment 2). Participants who read a short paragraph contextualising the to-be-learned information exhibited a significantly larger pretesting effect than participants who did not, with this interaction being observed regardless of whether memory was tested after a 5-min delay or 1-week delay, and regardless of whether contextualisation was manipulated between-subjects or within-subjects. These results suggest that what learners know prior to a pretest can have an impact on the extent to which learners benefit from that pretest.

Memory updating after retrieval: when new information is false or correct

We conducted three experiments testing the malleability of memory in incorporating new information following retrieval. All experiments used associative lists typical of the DRM paradigm [Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58(1), 17-22; Roediger, H. L., & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21(4), 803-814]. This paradigm enabled the evaluation of the integration of false information and correct information with the original information. In Experiment 1, participants studied DRM lists, and in a later phase either retrieved or restudied the lists and were presented with never-presented critical lures. The results of Experiment 1 showed that compared to restudy, retrieval enhanced the integration of subsequent false information, as measured by later recall in a follow-up test. In Experiments 2 and 3, after initial study, participants retrieved or studied incorrect information and received corrective feedback. The results showed that retrieval led to more error correction than restudy, when feedback was presented immediately. In general, this research suggests retrieval facilitates incorporation of new, related information, regardless of whether it is false or correct.

A mind-wandering account of the testing effect: Does context variation matter?

The learning benefits of retrieval practice have been linked to reduced mind-wandering, but the reasons why testing offers such an attentional advantage have scarcely been explored. Here, we investigate the extent that the inherent change in learning context during retrieval practice (i.e., interleaved study and retrieval) attenuates mind-wandering, relative to restudy (i.e., massed study). Learners (N = 120) either restudied video lectures (SSSS) or engaged in a combination of study and retrieval (SRSR). Further, they used either the same study mode - the video lecture (S) or its corresponding transcript (S') only (i.e., SSSS or S'S'S'S'; SRSR or S'RS'R), or different study modes - alternated between the video and its transcript (i.e., SS'SS' or S'SS'S; SRS'R or S'RSR). Learners' mind-wandering tendencies were captured using a direct-probing approach, and a free-recall test was administered 1 week later. Retrieval practice produced less mind-wandering than restudy, and this attentional difference mediated the recall advantage of retrieval practice. Of note, in the restudy condition, alternating between study modes inoculated against mind-wandering relative to using the same mode, but only for as long as the study mode remained "new" to learners - when they returned to a previously encountered "old" study mode, mind-wandering surged. In contrast, retrieval practice consistently sustained learners' attention over time, whether or not their study modes were the same or different. Theoretical implications for an attentional account of retrieval-based learning are discussed.

Does expressive writing or an instructional intervention reduce the impacts of test anxiety in a college classroom?

Test anxiety is a major concern in education because it causes uncomfortable feelings in test-anxious students and may reduce the validity of exam scores as a measure of learning. As such, brief and cost-effective interventions are necessary to minimize the negative impact of test anxiety on students’ academic performance. In the present experiment, we examine two such interventions: expressive writing (Experiment 1) and an instructional intervention (Experiment 2), with the latter developed from a similar intervention for stereotype threat. Across four authentic exams in a psychology class, students alternated between completing the intervention and a control task immediately before completing the exams. Neither intervention was effective at reducing test anxiety or improving exam performance. The present results suggest that these interventions may not be successful in addressing the impacts of test anxiety in all classroom settings.

Pretesting can be beneficial even when using the internet to answer questions

Research on the pretesting effect has shown that attempting to retrieve or generate information, even when unsuccessful, can potentiate the subsequent learning and remembering of that information. In the current research, we tested the hypothesis that when information can be accessed online, people may be less likely to retrieve or generate information on their own, thus making them less likely to benefit from the pretesting effect. The results of two experiments failed to provide support for this hypothesis. Participants remembered pretested information better than non-pretested information regardless of whether they were required to attempt to retrieve answers from memory or search for the answers using Google. The results suggest that the benefits of pretesting can be observed even when people rely on the internet to answer the questions they encounter.

Too much of a good thing: frequent retrieval can impair immediate new learning

Interpolated testing can reduce mind-wandering and proactive interference, and improve note-taking. However, recent research using face-name-profession triads, has also shown that interpolated testing can impair new learning (Davis, Chan, & Wilford, 2017). In the current study, we further examined the impact of switching from testing to new learning, but with objectively-true materials. The study employed a 2 (Interpolated task: Test vs. Restudy) × 3 (Task-switch frequency: 0, 11, 35) between-participants design. In two experiments, participants restudied or retrieved originally-learned flag-country associations and learned new flag-capital (Experiment 1) or flag-export (Experiment 2) associations. Task-switch frequency varied such that participants switched to new learning trial(s) after every restudy/test trial (35-switches), after every three restudy/test trials (11-switches), or did not switch at all (0-switch). The results further demonstrate that retrieving previously-learned material can impair learning of new associations by replicating Davis et al. (2017) with objectively-true materials.

Practicing Retrieval Facilitates Learning

How do we go about learning new information? This article reviews the importance of practicing retrieval of newly experienced information if one wants to be able to retrieve it again in the future. Specifically, practicing retrieval shortly after learning can slow the forgetting process. This benefit can be seen across various material types, and it seems prevalent in all ages and learner abilities and on all types of test. It can also be used to enhance student learning in a classroom setting. I review theoretical understanding of this phenomenon (sometimes referred to as the testing effect or as retrieval-based learning) and consider directions for future research.

The Forward Testing Effect is Immune to Acute Psychosocial Encoding/Retrieval Stress

The forward testing effect (FTE) refers to the finding that testing of previously studied information enhances memory for subsequently studied other information. Previous research demonstrated that the FTE is a robust phenomenon that generalizes across different materials and populations. The present study examined whether the FTE is robust under acute psychosocial encoding/retrieval stress. In each of two experimental conditions, participants studied three item lists in anticipation of final cumulative recall testing. In the testing condition, participants were tested immediately on lists 1 and 2, whereas in the restudy condition, they restudied lists 1 and 2. In both conditions, participants were tested immediately on list 3. Acute psychosocial stress was induced in participants prior to the encoding of item lists using the Trier social stress test for groups protocol. No stress was induced in a control group. Salivary cortisol, alpha amylase, and subjective stress were measured repeatedly to capture the biopsychological stress response. The results showed a significant FTE on list 3 recall, that is, testing of lists 1 and 2 enhanced the recall of list 3. No significant effect of stress on the FTE was observed, suggesting that the FTE is robust under acute psychosocial encoding/retrieval stress. The discussion provides suggestions for future research directions.

Using tests to reduce mind-wandering during learning review

Research suggests testing improves the retention of previously learned information. Here, we examined whether this might be due (in part) to the fact that tests help learners stay on task during the review stages of learning. In two experiments, participants encoded a list of words and later had an opportunity to review the material via a free recall test or re-reading the words. During review, participants provided self-reports as to whether their minds were on or off task. Results from both experiments show testing decreased mind-wandering. Importantly, this reduction in mind-wandering was associated with improved performance on a final memory test. These results suggest the mnemonic benefits associated with testing may stem not only from act of retrieval itself, but also from the fact that taking tests encourages a more efficient and engaged review of the material.

The feature boost in false memory: the roles of monitoring and critical item identifiability

The feature boost refers to increased false memories for word lists that are both associatively and categorically (C + A) related to a non-presented critical item (CI) relative to lists that are only associatively (NC-A) related [Coane, J. H., McBride, D. M., Termonen, M.-L., & Cutting, J. C. (2016). Categorical and associative relations increase false memory relative to purely associative relations. Memory & Cognition, 44(1), 37-49. doi:10.3758/s13421-015-0543-1]. We explored the replicability of the feature boost and its dependance on monitoring processes by explicitly warning participants about the nature of the lists or by asking participants to guess the CI (implicit warning). Overall, the feature boost was replicated. Guessing performance was higher for C + A lists than for NC-A lists. Explicit warnings were equally effective for both list types in reducing false memory relative to recall and to a no-recall math condition. When the CI was not guessed or recalled, the feature boost emerged. However, when the CI was guessed or previously recalled, false alarms did not differ as a function of list type. The feature boost seems to be driven in part by differences in the identifiability of the CI, such that CIs related to C + A lists are harder to identify and thus reject. These results suggest that differences in monitoring processes that are sensitive to CI identifiability contribute to the effect.

The role of emotion arousal in the retrieval practice effect

Many studies have shown that practicing retrieval produces better memory retention compared to restudy. Though previous literature has provided valuable insights about the retrieval practice effect, it is still unclear how emotion arousal influences the retrieval practice effect, and whether the effect would be manifested in recollection or familiarity processes. To answer these questions, in the current study, negative and neutral words were used as stimuli and participants were asked to perform a recognition test or restudy the words after initial study. At the end of the experiment, a final recognition test with involving the remember-know paradigm was shown. Behavioral data were collected with EEG recorded throughout the experiment. The behavioral retrieval practice effect was only found for the neutral but not the negative words. Consistently, significant ERP differences between the restudy and retrieval practice conditions were only found for neutral, but not negative items, which was a component from 700 to 900 ms at left-posterior electrode cluster. Moreover, we found that the effects of emotion arousal on the retrieval practice effect were mainly reflected in the recollection process. These findings provide behavioral and neural evidence that emotion arousal can influence the retrieval practice effect.

The Forward Testing Effect is Reliable and Independent of Learners' Working Memory Capacity

The forward testing effect refers to the finding that retrieval practice of previously studied information enhances learning and retention of subsequently studied other information. While most of the previous research on the forward testing effect examined group differences, the present study took an individual differences approach to investigate this effect. Experiment 1 examined whether the forward effect has test-retest reliability between two experimental sessions. Experiment 2 investigated whether the effect is related to participants' working memory capacity. In both experiments (and each session of Experiment 1), participants studied three lists of items in anticipation of a final cumulative recall test. In the testing condition, participants were tested immediately on lists 1 and 2, whereas in the restudy condition, they restudied lists 1 and 2. In both conditions, participants were tested immediately on list 3. On the group level, the results of both experiments demonstrated a forward testing effect, with interim testing of lists 1 and 2 enhancing immediate recall of list 3. On the individual level, the results of Experiment 1 showed that the forward effect on list 3 recall has moderate test-retest reliability between two experimental sessions. In addition, the results of Experiment 2 showed that the forward effect on list 3 recall does not depend on participants' working memory capacity. These findings suggest that the forward testing effect is reliable at the individual level and affects learners at a wide range of working memory capacities alike. The theoretical and practical implications of the findings are discussed.

Testing enhances motor practice

We investigated how retrieval of a set of newly learned motor sequences influences subsequent learning of another set of motor sequences. In four experiments, retrieval reduced an acceleration of movement execution over subsequent study trials. This relative slowing-down was associated with better recall performance in a final memory test. Explicit retrievability of motor sequences benefited from longer study-trial response times (RTs), suggesting that retrieval caused more attentive encoding. The use of motor sequences requiring overt action during encoding allowed for this demonstration of a twofold forward effect of testing on encoding quality and on recall. Experiment 1 adopted a paradigm used in previous studies with verbal materials. Experiment 2 changed the test format to be less susceptible to interference. Experiments 3 and 4 additionally switched from a between-participants design to a within-participants design. These modifications did not affect the occurrence of the twofold forward effect of testing but enabled detecting a correlation between recall and study-trial performance that had been precluded by the strongly interference-dependent test format of the original paradigm. Our findings demonstrate an immediate learning benefit of testing. It enhances encoding in subsequent study trials.

Telling a good story: The effects of memory retrieval and context processing on eyewitness suggestibility

Witnesses are likely to describe a crime many times before testifying or encountering misinformation about that crime. Research examining the effect of retrieval on later suggestibility has yielded mixed results. LaPaglia and Chan manipulated whether misinformation was presented in a narrative or misleading questions, and they found that retrieval increased suggestibility when misinformation was presented in a narrative, but reduced suggestibility when the same misinformation was presented in questions. In the current study, we aimed to address why these differences occurred. Specifically, we examined whether contextual detail and narrative coherence during misinformation exposure influenced the relation between retrieval and suggestibility. Participants watched a robbery video and some were questioned about the event afterwards. They were then exposed to misinformation presented in a narrative (Experiment 1) or questions (Experiment 2) before taking a final memory test. Testing enhanced suggestibility when the misinformation phase reinstated contextual information of the event, but not when the misinformation phase included few contextual details–regardless of whether the misinformation was in a narrative or questions. In Experiment 3, disrupting narrative coherence by randomizing the order of contextual information eliminated retrieval-enhanced suggestibility. Therefore, context processing during the post-event information phase influences whether retrieval enhances or reduces eyewitness suggestibility.