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In three experiments, we investigated whether memory tests enhance learning and reduce forgetting more than additional study opportunities do. Subjects learned obscure facts (Experiments 1 and 2) or Swahili-English word pairs (Experiment 3) by either completing a test with feedback (test/study) or receiving an additional study opportunity (study). Recall was tested after 5 min or 1, 2, 7, 14, or 42 days. We explored forgetting by means of an ANOVA and also by fitting a power function to the data. In all three experiments, testing enhanced overall recall more than restudying did. According to the power function, in two out of three experiments, testing also reduced forgetting more than restudying did, although this was not always the case according to the ANOVA. We discuss the implications of these results both for approaches to measuring forgetting and for the use of tests in promoting long-term retention. The stimuli used in these experiments may be found at www.psychonomic.org/archive. [ABSTRACT FROM AUTHOR]

Recent evidence indicates that in intermixed recognition testing of different stimulus classes, people can apply different decision criteria (a criterion shift) to stimulus classes distinguished by the study-test delay (Singer, Gagnon, & Richards, 2002), but not by a conspicuous strength manipulation (Stretch & Wixted, 1998b). In an attempt to reconcile these differences, we applied Singer et al.'s text retrieval method to word recognition. People first studied blocked items from each of five categories. After a delay, five new category lists were presented. After each one, the participants recognized intermixed targets and distractors from the current category and one of the earlier ones. At delays of up to 40 min, the answering criteria for immediate and delayed categories were indistinguishable. At delays of 2 days, in contrast, however, both yes-no and confidence-rating data indicated that more lenient criteria were applied to delayed than to immediate test items. This suggests that people can use the delay between study and test to flexibly adjust the decision criteria of word recognition. [ABSTRACT FROM AUTHOR]

Research on best practices in theory assessment highlights that testing theories is challenging because they inherit a new set of assumptions as soon as they are linked to a specific methodology. In this article, we integrate and build on this work by demonstrating the breadth of these challenges. We show that tracking auxiliary assumptions is difficult because they are made at different stages of theory testing and at multiple levels of a theory. We focus on these issues in a reanalysis of a seminal study and its replications, both of which use a simple working-memory paradigm and a mainstream computational modeling approach. These studies provide the main evidence for "all-or-none" recognition models of visual working memory and are still used as the basis for how to measure performance in popular visual working-memory tasks. In our reanalysis, we find that core practical auxiliary assumptions were unchecked and violated; the original model comparison metrics and data were not diagnostic in several experiments. Furthermore, we find that models were not matched on "theory general" auxiliary assumptions, meaning that the set of tested models was restricted, and not matched in theoretical scope. After testing these auxiliary assumptions and identifying diagnostic testing conditions, we find evidence for the opposite conclusion. That is, continuous resource models outperform all-or-none models. Together, our work demonstrates why tracking and testing auxiliary assumptions remains a fundamental challenge, even in prominent studies led by careful, computationally minded researchers. Our work also serves as a conceptual guide on how to identify and test the gamut of auxiliary assumptions in theory assessment, and we discuss these ideas in the context of contemporary approaches to scientific discovery., (© 2024. Crown.)

A photo lineup, which is a cross between an old/new and a forced-choice recognition memory test, consists of one suspect, whose face was either seen before or not, and several physically similar fillers. First, the participant/witness must decide whether the person who was previously seen is present (old/new) and then, if present, choose the previously seen target (forced choice). Competing signal-detection models of eyewitness identification performance make different predictions about how certain variables will affect a witness's ability to discriminate previously seen (guilty) suspects from new (innocent) suspects. One key variable is the similarity of the fillers to the suspect in the lineup, and another key variable is the size of the lineup (i.e., the number of fillers). Previous research investigating the role of filler similarity has supported one model, known as the Ensemble model, whereas previous research investigating the role of lineup size has supported a competing model, known as the Independent Observations model. We simultaneously manipulated these two variables (filler similarity and lineup size) and found a pattern that is not predicted by either model. When the fillers were highly similar to the suspect, increasing lineup size reduced discriminability, but when the fillers were dissimilar to the suspect, increasing lineup size enhanced discriminability. The results suggest that each additional filler adds noise to the decision-making process and that this noise factor is minimized by maximizing filler dissimilarity. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

This article memorializes Norman Henry Anderson (1925-2022), best known for his information integration theory (IIT). Norman Anderson's work was influential in its time, and his legacy endures. He was the recipient of the 1972 American Association for the Advancement of Science Prize for Behavioral Science Research, and, as a tribute to his work, scholars in the field established a conference that continues to this day: the International Information Integration Theory/Functional Measurement Conference. Highlights of Anderson's career and professional contributions are noted. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

We argue that critical areas of memory research rely on problematic measurement practices and provide concrete suggestions to improve the situation. In particular, we highlight the prevalence of memory studies that use tasks (like the "old/new" task: "have you seen this item before? yes/no") where quantifying performance is deeply dependent on counterfactual reasoning that depends on the (unknowable) distribution of underlying memory signals. As a result of this difficulty, different literatures in memory research (e.g., visual working memory, eyewitness identification, picture memory, etc.) have settled on a variety of fundamentally different metrics to get performance measures from such tasks (e.g., A', corrected hit rate, percent correct, d', diagnosticity ratios, K values, etc.), even though these metrics make different, contradictory assumptions about the distribution of latent memory signals, and even though all of their assumptions are frequently incorrect. We suggest that in order for the psychology and neuroscience of memory to become a more cumulative, theory-driven science, more attention must be given to measurement issues. We make a concrete suggestion: The default memory task for those simply interested in performance should change from old/new ("did you see this item'?") to two-alternative forced-choice ("which of these two items did you see?"). In situations where old/new variants are preferred (e.g., eyewitness identification; theoretical investigations of the nature of memory signals), receiver operating characteristic (ROC) analysis should be performed rather than a binary old/new task., (© 2022. The Psychonomic Society, Inc.)

Police investigators worldwide use lineups to test an eyewitness's memory of a perpetrator. A typical lineup consists of one suspect (who is innocent or guilty) plus five or more fillers who resemble the suspect and who are known to be innocent. Although eyewitness identification decisions were once biased by police pressure and poorly constructed lineups, decades of social science research led to the development of reformed lineup procedures that provide a more objective test memory. Under these improved testing conditions, cognitive models of memory can be used to better understand and ideally enhance eyewitness identification performance. In this regard, one question that has bedeviled the field for decades is how similar the lineup fillers should be to the suspect to optimize performance. Here, we model the effects of manipulating filler similarity to better understand why such manipulations have the intriguing effects they do. Our findings suggest that witnesses rely on a decision variable consisting of the degree to which the memory signal for a particular face in the lineup stands out relative to the crowd of memory signals generated by the set of faces in the lineup. The use of that decision variable helps to explain why discriminability is maximized by choosing fillers that match the suspect on basic facial features typically described by the eyewitness (e.g., age, race, gender) but who otherwise are maximally dissimilar to the suspect. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Change detection tasks are commonly used to measure and understand the nature of visual working memory capacity. Across three experiments, we examine whether the nature of the memory signals used to perform change detection are continuous or all-or-none and consider the implications for proper measurement of performance. In Experiment 1, we find evidence from confidence reports that visual working memory is continuous in strength, with strong support for an equal variance signal detection model with no guesses or lapses. Experiments 2 and 3 test an implication of this, which is that K should confound response criteria and memory. We found K values increased by roughly 30% when criteria are shifted despite no change in the underlying memory signals. Overall, our data call into question a large body of work using threshold measures, like K , to analyze change detection data. This metric confounds response bias with memory performance and is inconsistent with the vast majority of visual working memory models, which propose variations in precision or strength are present in working memory. Instead, our data indicate an equal variance signal detection model (and thus, d ')-without need for lapses or guesses-is sufficient to explain change detection performance. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Slamecka and McElree (1983) and Rivera-Lares et al. (2022), like others before them, factorially manipulated the number of learning trials and the retention interval. The results revealed two unsurprising main effects: (a) the more study trials, the higher the initial degree of learning, and (b) the longer the retention interval, the more items were forgotten. However, across many experiments, the interaction was not significant, a finding that is often interpreted to mean that the degree of learning is independent of the absolute rate of forgetting (i.e., the absolute number of items forgotten per unit time). Yet there is considerable tension between that interpretation and the fact that forgetting has long been characterized by a power law, according to which the absolute rate of forgetting is not a particularly meaningful measure. When the power function is fit to the same data, the results show that a higher degree of learning results in a lower relative (i.e., proportional) rate of forgetting. This raises an interesting question: which of the two definitions of "forgetting rate" (absolute vs. relative) is theoretically relevant? Here, I make the case that it is the relative rate of forgetting. Theoretically, the explanation of why a higher degree of learning is associated with a lower relative rate of forgetting may be related to why, as observed by Jost (1897) long ago, the passage of time itself is associated with a lower relative rate of forgetting. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

A fundamental goal of scientific research is to generate true positives (i.e., authentic discoveries). Statistically, a true positive is a significant finding for which the underlying effect size (δ) is greater than 0, whereas a false positive is a significant finding for which δ equals 0. However, the null hypothesis of no difference (δ = 0) may never be strictly true because innumerable nuisance factors can introduce small effects for theoretically uninteresting reasons. If δ never equals zero, then with sufficient power, every experiment would yield a significant result. Yet running studies with higher power by increasing sample size (N) is one of the most widely agreed upon reforms to increase replicability. Moreover, and perhaps not surprisingly, the idea that psychology should attach greater value to small effect sizes is gaining currency. Increasing N without limit makes sense for purely measurement-focused research, where the magnitude of δ itself is of interest, but it makes less sense for theory-focused research, where the truth status of the theory under investigation is of interest. Increasing power to enhance replicability will increase true positives at the level of the effect size (statistical true positives) while increasing false positives at the level of theory (theoretical false positives). With too much power, the cumulative foundation of psychological science would consist largely of nuisance effects masquerading as theoretically important discoveries. Positive predictive value at the level of theory is maximized by using an optimal N, one that is neither too small nor too large., (© 2022. The Psychonomic Society, Inc.)

Prior studies of the neural representation of episodic memory in the human hippocampus have identified generic memory signals representing the categorical status of test items (novel vs. repeated), whereas other studies have identified item specific memory signals representing individual test items. Here, we report that both kinds of memory signals can be detected in hippocampal neurons in the same experiment. We recorded single-unit activity from four brain regions (hippocampus, amygdala, anterior cingulate, and prefrontal cortex) of epilepsy patients as they completed a continuous recognition task. The generic signal was found in all four brain regions, whereas the item-specific memory signal was detected only in the hippocampus and reflected sparse coding. That is, for the item-specific signal, each hippocampal neuron responded strongly to a small fraction of repeated words, and each repeated word elicited strong responding in a small fraction of neurons. The neural code was sparse, pattern-separated, and limited to the hippocampus, consistent with longstanding computational models. We suggest that the item-specific episodic memory signal in the hippocampus is fundamental, whereas the more widespread generic memory signal is derivative and is likely used by different areas of the brain to perform memory-related functions that do not require item-specific information.

The reliability of any type of forensic evidence (e.g., forensic DNA) is assessed by testing its information value when it is not contaminated and is properly tested. Assessing the reliability of forensic memory evidence should be no exception to that rule. Unfortunately, testing a witness's memory irretrievably contaminates it. Thus, only the first (properly conducted) test is relevant to the question of whether eyewitness memory is reliable. With few exceptions, the results of studies conducted in the lab and in the real world show that confidence is highly predictive of accuracy on the first test, and high-confidence often implies high accuracy. The fact that many eyewitnesses are known to have made high-confidence misidentifications in the courtroom has cemented the almost universal impression that eyewitness memory is unreliable. However, it is the criminal justice system that is guilty of unwittingly using contaminated memory evidence (relying on the last memory test, in court) in conjunction with an improper testing procedure (namely, a courtroom showup) to win convictions of the innocent. That mistake should no longer be blamed on the unreliability of eyewitness memory.

Berkowitz et al. (Berkowitz, S. R., Garrett, B. L., Fenn, K. M., & Loftus, E. F. (2020). Convicting with confidence? Why we should not over-rely on eyewitness confidence. Memory . https://doi.org/10.1080/09658211.2020.1849308) attribute to us the claim that "confidence trumps all", and the few out-of-context quotations they selected can certainly be used to create that false impression. However, it is easily disproved, and we do so here. The notion that "confidence trumps all" is the mistake that the jurors made in the DNA exoneration cases, not a position that we have ever advocated.

Eyewitness misidentifications are almost always made with high confidence in the courtroom. The courtroom is where eyewitnesses make their last identification of defendants suspected of (and charged with) committing a crime. But what did those same eyewitnesses do on the first identification test, conducted early in a police investigation? Despite testifying with high confidence in court, many eyewitnesses also testified that they had initially identified the suspect with low confidence or failed to identify the suspect at all. Presenting a lineup leaves the eyewitness with a memory trace of the faces in the lineup, including that of the suspect. As a result, the memory signal generated by the face of that suspect will be stronger on a later test involving the same witness, even if the suspect is innocent. In that sense, testing memory contaminates memory. These considerations underscore the importance of a newly proposed recommendation for conducting eyewitness identifications: Avoid repeated identification procedures with the same witness and suspect . This recommendation applies not only to additional tests conducted by police investigators but also to the final test conducted in the courtroom, in front of the judge and jury.

The simultaneous six-pack photo lineup is a standard eyewitness identification procedure, consisting of one police suspect plus five physically similar fillers. The photo lineup is either a target-present array (the suspect is guilty) or a target-absent array (the suspect is innocent). The eyewitness is asked to search the six photos in the array with respect to a target template stored in memory (namely, the memory of the perpetrator's face). If the witness determines that the perpetrator is in fact in the lineup (detection), then the next step is to specify the position of the perpetrator's face in the lineup (localization). The witness may also determine that the perpetrator is not present and reject the lineup. In other words, a police lineup is a detection-plus-localization visual search task. Signal detection concepts that have long guided thinking about visual search have recently had a significant impact on our understanding of police lineups.

Eyewitness identification via lineup procedures is an important and widely used source of evidence in criminal cases. However, the scientific literature provides inconsistent guidance on a very basic feature of lineup procedure: lineup size. In two experiments, we examined whether the number of fillers affects diagnostic accuracy in a lineup, as assessed with receiver-operating characteristic (ROC) analysis. Showups (identification procedures with one face) led to lower discriminability than simultaneous lineups. However, in neither experiment did the number of fillers in a lineup affect discriminability. We also evaluated competing models of decision-making from lineups. This analysis indicated that the standard Independent Observations (IO) model, which assumes a decision rule based on the comparison of memory strength signals generated by each face in a lineup, is incapable of reproducing the lower level of performance evident in showups. We could not adjudicate between the Ensemble model, which assumes a decision rule based on the comparison of the strength of each face with the mean strength across the lineup, and a newly introduced Dependent Observations model, which adopts the same decision rule as the IO model, but with correlated signals across faces. We draw lessons for users of lineup procedures and for basic research on eyewitness decision making. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The present study examined task order, language, and frequency effects on list memory to investigate how bilingualism affects recognition memory. In Experiment 1, 64 bilinguals completed a recognition memory task including intermixed high and medium frequency words in English and another list in Spanish. In Experiment 2, 64 bilinguals and 64 monolinguals studied lists with only high frequency English words and a separate list with only low frequency English words, in counterbalanced order followed by a recognition test. In Experiment 1, bilinguals who completed the task in the dominant language first outperformed bilinguals tested in the nondominant language first, and order effects were not stronger in the dominant language. In Experiment 2, participants who were tested with high frequency word lists first outperformed those tested with low frequency word lists first. Regardless of language and testing order, memory for English and high frequency words was lower than memory for Spanish and medium frequency (in Experiment 1) or low frequency (in Experiment 2) words. Order effects on recognition memory patterned differently from previously reported effects on picture naming in ways that do not suggest between language interference and instead invite an analogy between language dominance and frequency of use (i.e., dominant language = higher frequency) as the primary factor affecting bilingual recognition memory.

The relationship between confidence and accuracy in recognition memory is important in real-world settings (e.g., eyewitness identification) and is also important to understand at a theoretical level. Signal detection theory assumes that recognition decisions are based on continuous underlying memory signals and therefore inherently predicts that the relationship between confidence and accuracy will be continuous. Almost invariably, the empirical data accord with this prediction. Threshold models instead assume that recognition decisions are based on discrete-state memory signals. As a result, these models do not inherently predict a continuous confidence-accuracy relationship. However, they can accommodate that result by adding hypothetical mapping relationships between discrete states and the confidence rating scale. These mapping relationships are thought to arise from a variety of factors, including demand characteristics (e.g., instructing participants to distribute their responses across the confidence scale). However, until such possibilities are experimentally investigated in the context of a recognition memory experiment, there is no sense in which threshold models adequately explain confidence ratings at a theoretical level. Here, we tested whether demand characteristics might account for the mapping relationships required by threshold models and found that confidence was continuously related to accuracy (almost identically so) both in the presence of strong experimenter demands and in their absence. We conclude that confidence ratings likely reflect the strength of a continuous underlying memory signal, not an attempt to use the confidence scale in a manner that accords with the perceived expectations of the experimenter.

A typical police lineup contains a photo of one suspect (who is innocent in a target-absent lineup and guilty in a target-present lineup) plus photos of five or more fillers who are known to be innocent. To create a fair lineup in which the suspect does not stand out, two filler selection methods are commonly used. In the first, fillers are selected if they are similar in appearance to the suspect. In the second, fillers are selected if they possess facial features included in the witness's description of the culprit (e.g., "20-y-old white male"). The police sometimes use a combination of the two methods by selecting description-matched fillers whose appearance is also similar to that of the suspect in the lineup. Decades of research on which approach is better remains unsettled. Here, we tested a counterintuitive prediction made by a formal model based on signal detection theory: From a pool of acceptable description-matched photos, selecting fillers whose appearance is otherwise dissimilar to the suspect should increase the hit rate without affecting the false-alarm rate (increasing discriminability). In Experiment 1, we confirmed this prediction using a standard mock-crime paradigm. In Experiment 2, the effect on discriminability was reversed (as also predicted by the model) when fillers were matched on similarity to the perpetrator in both target-present and target-absent lineups. These findings suggest that signal-detection theory offers a useful theoretical framework for understanding eyewitness identification decisions made from a police lineup., Competing Interests: The authors declare no competing interest.

Almost all models of visual memory implicitly assume that errors in mnemonic representations are linearly related to distance in stimulus space. Here we show that neither memory nor perception are appropriately scaled in stimulus space; instead, they are based on a transformed similarity representation that is nonlinearly related to stimulus space. This result calls into question a foundational assumption of extant models of visual working memory. Once psychophysical similarity is taken into account, aspects of memory that have been thought to demonstrate a fixed working memory capacity of around three or four items and to require fundamentally different representations-across different stimuli, tasks and types of memory-can be parsimoniously explained with a unitary signal detection framework. These results have substantial implications for the study of visual memory and lead to a substantial reinterpretation of the relationship between perception, working memory and long-term memory.

Recent research in the eyewitness identification literature has investigated whether simultaneous or sequential lineups yield better discriminability. In standard eyewitness identification experiments, subjects view a mock-crime video and then are tested only once, requiring large samples for adequate power. However, there is no reason why theories of simultaneous versus sequential lineup performance cannot be tested using more traditional recognition memory tasks. In two experiments, subjects studied DRM (Deese-Roediger-McDermott) word lists (e.g., bed, rest, tired, ...) and were tested using "lineups" in which six words were presented either simultaneously or sequentially. A studied word (e.g., tired) served as the guilty suspect in target-present lineups, unstudied related words (e.g., nap) served as fillers in target-present and target-absent lineups, and critical lures (e.g., sleep) were included in some target-present and target-absent lineups as well, to serve as attractive alternatives to the target word (or suspect). ROC analyses showed that the simultaneous test format generally yielded superior discriminability performance compared to the sequential test format, whether or not the critical lure was present in the lineup.

Encoding activity in the medial temporal lobe, presumably evoked by the presentation of stimuli (postonset activity), is known to predict subsequent memory. However, several independent lines of research suggest that preonset activity also affects subsequent memory. We investigated the role of preonset and postonset single-unit and multiunit activity recorded from epilepsy patients as they completed a continuous recognition task. In this task, words were presented in a continuous series and eventually began to repeat. For each word, the patient's task was to decide whether it was novel or repeated. We found that preonset spiking activity in the hippocampus (when the word was novel) predicted subsequent memory (when the word was later repeated). Postonset activity during encoding also predicted subsequent memory, but was simply a continuation of preonset activity. The predictive effect of preonset spiking activity was much stronger in the hippocampus than in three other brain regions (amygdala, anterior cingulate, and prefrontal cortex). In addition, preonset and postonset activity around the encoding of novel words did not predict memory performance for novel words (i.e., correctly classifying the word as novel), and preonset and postonset activity around the time of retrieval did not predict memory performance for repeated words (i.e., correctly classifying the word as repeated). Thus, the only predictive effect was between preonset activity (along with its postonset continuation) at the time of encoding and subsequent memory. Taken together, these findings indicate that preonset hippocampal activity does not reflect general arousal/attention but instead reflects what we term "attention to encoding.", Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

The perceived replication crisis and the reforms designed to address it are grounded in the notion that science is a binary signal detection problem. However, contrary to null hypothesis significance testing (NHST) logic, the magnitude of the underlying effect size for a given experiment is best conceptualized as a random draw from a continuous distribution, not as a random draw from a dichotomous distribution (null vs. alternative). Moreover, because continuously distributed effects selected using a P < 0.05 filter must be inflated, the fact that they are smaller when replicated (reflecting regression to the mean) is no reason to sound the alarm. Considered from this perspective, recent replication efforts suggest that most published P < 0.05 scientific findings are "true" (i.e., in the correct direction), with observed effect sizes that are inflated to varying degrees. We propose that original science is a screening process, one that adopts NHST logic as a useful fiction for selecting true effects that are potentially large enough to be of interest to other scientists. Unlike original science, replication science seeks to precisely measure the underlying effect size associated with an experimental protocol via large- N direct replication, without regard for statistical significance. Registered reports are well suited to (often resource-intensive) direct replications, which should focus on influential findings and be published regardless of outcome. Conceptual replications play an important but separate role in validating theories. However, because they are part of NHST-based original science, conceptual replications cannot serve as the field's self-correction mechanism. Only direct replications can do that., Competing Interests: The authors declare no competing interest.

Presenting the police suspect alongside similar-looking people (a lineup) results in more accurate eyewitness identification decisions than presenting the suspect alone (a showup). Why are lineups better than showups? Diagnostic-feature-detection theory suggests that lineups enhance witnesses' ability to discriminate between innocent and guilty suspects, because facial features can be compared across lineup members. Filler-siphoning suggests that the presence of other lineup members siphons some of the incorrect identifications that would otherwise land on the innocent suspect. To test these 2 accounts, over 3,600 subjects across 3 experiments watched a mock-crime video and were presented with either a showup, a simultaneous lineup, or a simultaneous showup (a novel procedure). Subjects in the simultaneous showup condition saw the suspect and 5 similar-looking faces, but, unlike a lineup, could not identify the other faces. Presenting similar-looking faces alongside the suspect (simultaneous showup and lineup) enhanced subjects' ability to discriminate between innocent and guilty suspects compared with presenting the suspect alone (showup) as measured by Area Under the ROC Curve (pAUC) and fitting a signal-detection model. These results show, for the first time, that the discriminability advantage in simultaneous lineups is because of the comparison of multiple faces as predicted by diagnostic-feature-detection theory, but not the filler-siphoning account. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Objective: The Executive Committee of the American Psychology-Law Society (Division 41 of the American Psychological Association) appointed a subcommittee to update the influential 1998 scientific review paper on guidelines for eyewitness identification procedures., Method: This was a collaborative effort by six senior eyewitness researchers, who all participated in the writing process. Feedback from members of AP-LS and the legal communities was solicited over an 18-month period., Results: The results yielded nine recommendations for planning, designing, and conducting eyewitness identification procedures. Four of the recommendations were from the 1998 article and concerned the selection of lineup fillers, prelineup instructions to witnesses, the use of double-blind procedures, and collection of a confidence statement. The additional five recommendations concern the need for law enforcement to conduct a prelineup interview of the witness, the need for evidence-based suspicion before conducting an identification procedure, video-recording of the entire procedure, avoiding repeated identification attempts with the same witness and same suspect, and avoiding the use of showups when possible and improving how showups are conducted when they are necessary., Conclusions: The reliability and integrity of eyewitness identification evidence is highly dependent on the procedures used by law enforcement for collecting and preserving the eyewitness evidence. These nine recommendations can advance the reliability and integrity of the evidence. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Signal detection theory is one of psychology's most well-known and influential theoretical frameworks. However, the conceptual hurdles that had to be overcome before the theory could finally emerge in its modern form in the early 1950s seem to have been largely forgotten. Here, I trace the origins of signal detection theory, beginning with Fechner's (1860/1966) Elements of Psychophysics . Over and above the Gaussian-based mathematical framework conceived by Fechner in 1860, nearly a century would pass before psychophysicists finally realized in 1953 that the distribution of sensations generated by neural noise falls above, not below, the threshold of conscious awareness. An extensive body of single-unit recording and neuroimaging research conducted since then supports the idea that sensory noise yields genuinely felt conscious sensations even in the complete absence of stimulation. That hard-to-come-by insight in 1953 led immediately to the notion of a movable decision criterion and to the methodology of receiver operating characteristic (ROC) analysis. Over the ensuing years, signal detection theory and ROC analysis have had an enormous impact on basic and applied science alike. Yet, in some quarters of our field, that fact appears to be virtually unknown. By tracing both its fascinating origins and its phenomenal impact, I hope to illustrate why no area of experimental psychology should ever be oblivious to signal detection theory. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

The core functional organization of the primate brain is remarkably conserved across the order, but behavioral differences evident between species likely reflect derived modifications in the underlying neural processes. Here, we performed the first study to directly compare visual recognition memory in two primate species-rhesus macaques and marmoset monkeys-on the same visual preferential looking task as a first step toward identifying similarities and differences in this cognitive process across the primate phylogeny. Preferences in looking behavior on the task were broadly similar between the species, with greater looking times for novel images compared with repeated images as well as a similarly strong preference for faces compared with other categories. Unexpectedly, we found large behavioral differences among the two species in looking behavior independent of image familiarity. Marmosets exhibited longer looking times, with greater variability compared with macaques, regardless of image content or familiarity. Perhaps most strikingly, marmosets shifted their gaze across the images more quickly, suggesting a different behavioral strategy when viewing images. Although such differences limit the comparison of recognition memory across these closely related species, they point to interesting differences in the mechanisms underlying active vision that have significant implications for future neurobiological investigations with these two nonhuman primate species. Elucidating whether these patterns are reflective of species or broader phylogenetic differences (e.g., between New World and Old World monkeys) necessitates a broader sample of primate taxa from across the Order.

Cognitive psychologists are familiar with how their expertise in understanding human perception, memory, and decision-making is applicable to the justice system. They may be less familiar with how their expertise in statistical decision-making and their comfort working in noisy real-world environments is just as applicable. Here we show how this expertise in ideal-observer models may be leveraged to calculate the probability of guilt of Gary Leiterman, a man convicted of murder on the basis of DNA evidence. We show by common probability theory that Leiterman is likely a victim of a tragic contamination event rather than a murderer. Making any calculation of the probability of guilt necessarily relies on subjective assumptions. The conclusion about Leiterman's innocence is not overly sensitive to the assumptions-the probability of innocence remains high for a wide range of reasonable assumptions. We note that cognitive psychologists may be well suited to make these calculations because as working scientists they may be comfortable with the role a reasonable degree of subjectivity plays in analysis.

Understandably enough, most people are under the impression that eyewitness memory is unreliable. For example, research shows that memory is malleable, so much so that people can come to confidently remember traumatic events that never actually happened. In addition, eyewitness misidentifications made with high confidence in a court of law are known to have played a role in more than 70% of the 358 wrongful convictions that have been overturned based on DNA evidence since 1989. However, recent research demonstrates that eyewitness confidence is highly indicative of accuracy on an initial, uncontaminated, properly administered photo lineup. In other words, low confidence indicates that the test result (i.e., the ID) is inconclusive, whereas high confidence indicates that the test result is far more conclusive. Critically, for the DNA exonerees who were misidentified by an eyewitness in a court of law, in every case where their initial confidence can be determined, the eyewitness appropriately expressed low confidence. For any other kind of evidence (e.g., DNA, fingerprints), an inconclusive test result like that would have been the end of it. By contrast, in the case of eyewitness evidence, investigators repeatedly tested (and therefore unwittingly contaminated) memory until a seemingly conclusive high-confidence ID could be presented to the jury. Blaming eyewitness memory for the failure of the criminal justice system to accept the inconclusive nature of the initial (uncontaminated) eyewitness evidence seems misguided. In addition to exonerating the innocent defendants who were wrongfully convicted, the time has come to exonerate eyewitness memory too., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Estimator variables are factors that can affect the accuracy of eyewitness identifications but that are outside of the control of the criminal justice system. Examples include (1) the duration of exposure to the perpetrator, (2) the passage of time between the crime and the identification (retention interval), (3) the distance between the witness and the perpetrator at the time of the crime. Suboptimal estimator variables (e.g., long distance) have long been thought to reduce the reliability of eyewitness identifications (IDs), but recent evidence suggests that this is not true of IDs made with high confidence and may or may not be true of IDs made with lower confidence. The evidence suggests that though suboptimal estimator variables decrease discriminability (i.e., the ability to distinguish innocent from guilty suspects), they do not decrease the reliability of IDs made with high confidence. Such findings are inconsistent with the longstanding "optimality hypothesis" and therefore require a new theoretical framework. Here, we propose that a signal-detection-based likelihood ratio account-which has long been a mainstay of basic theories of recognition memory-naturally accounts for these findings. (PsycINFO Database Record, ((c) 2018 APA, all rights reserved).)

Face recognition memory is often tested by the police using a photo lineup, which consists of one suspect, who is either innocent or guilty, and five or more physically similar fillers, all of whom are known to be innocent. For many years, lineups were investigated in lab studies without guidance from standard models of recognition memory. More recently, signal detection theory has been used to conceptualize lineup memory and to motivate receiver operating characteristic (ROC) analysis of lineup performance. Here, we describe three competing signal-detection models of lineup memory, derive their likelihood functions, and fit them to empirical ROC data. We also introduce the notion that memory signals generated by the faces in a lineup are likely to be correlated because, by design, those faces share features. The models we investigate differ in their predictions about the effect that correlated memory signals should have on the ability to discriminate innocent from guilty suspects. A popular compound signal detection model known as the Integration model predicts that correlated memory signals should impair discriminability. Empirically, this model performed so poorly that, going forward, it should probably be abandoned. The best-fitting model incorporates a principle known as "ensemble coding," which predicts that correlated memory signals should enhance discriminability. The ensemble model aligns with a previously proposed theory of eyewitness identification according to which the simultaneous presentation of faces in a lineup enhances discriminability compared to when faces are presented in isolation because it permits eyewitnesses to detect and discount non-diagnostic facial features., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Although certain pockets within the broad field of academic psychology have come to appreciate that eyewitness memory is more reliable than was once believed, the prevailing view, by far, is that eyewitness memory is unreliable-a blanket assessment that increasingly pervades the legal system. On the surface, this verdict seems unavoidable: Research convincingly shows that memory is malleable, and eyewitness misidentifications are known to have played a role in most of the DNA exonerations of the innocent. However, we argue here that, like DNA evidence and other kinds of scientifically validated forensic evidence, eyewitness memory is reliable if it is not contaminated and if proper testing procedures are used. This conclusion applies to eyewitness memory broadly conceived, whether the test involves recognition (from a police lineup) or recall (during a police interview). From this perspective, eyewitness memory has been wrongfully convicted of mistakes that are better construed as having been committed by other actors in the legal system, not by the eyewitnesses themselves. Eyewitnesses typically provide reliable evidence on an initial, uncontaminated memory test, and this is true even for most of the wrongful convictions that were later reversed by DNA evidence.

The available real-world evidence suggests that, on an initial test, eyewitness memory is often reliable. Ironically, even the DNA exoneration cases-which generally involved nonpristine testing conditions and which are usually construed as an indictment of eyewitness memory-show how reliable an initial test of eyewitness memory can be in the real world. We endorse the use of pristine testing procedures, but their absence does not automatically imply that eyewitness memory is unreliable.

Neurocomputational models have long posited that episodic memories in the human hippocampus are represented by sparse, stimulus-specific neural codes. A concomitant proposal is that when sparse-distributed neural assemblies become active, they suppress the activity of competing neurons (neural sharpening). We investigated episodic memory coding in the hippocampus and amygdala by measuring single-neuron responses from 20 epilepsy patients (12 female) undergoing intracranial monitoring while they completed a continuous recognition memory task. In the left hippocampus, the distribution of single-neuron activity indicated that only a small fraction of neurons exhibited strong responding to a given repeated word and that each repeated word elicited strong responding in a different small fraction of neurons. This finding reflects sparse distributed coding. The remaining large fraction of neurons exhibited a concurrent reduction in firing rates relative to novel words. The observed pattern accords with longstanding predictions that have previously received scant support from single-cell recordings from human hippocampus., Competing Interests: The authors declare no conflict of interest.

In vast contrast to the multitude of lineup studies that report on the link between decision time, confidence, and identification accuracy, only a few studies looked at these associations for showups, with results varying widely across studies. We therefore set out to test the individual and combined value of decision time and post-decision confidence for diagnosing the accuracy of positive showup decisions using confidence-accuracy characteristic curves and Bayesian analyses. Three-hundred-eighty-four participants viewed a stimulus event and were subsequently presented with two showups which could be target-present or target-absent. As expected, we found a negative decision time-accuracy and a positive post-decision confidence-accuracy correlation for showup selections. Confidence-accuracy characteristic curves demonstrated the expected additive effect of combining both postdictors. Likewise, Bayesian analyses, taking into account all possible target-presence base rate values showed that fast and confident identification decisions were more diagnostic than slow or less confident decisions, with the combination of both being most diagnostic for postdicting accurate and inaccurate decisions. The postdictive value of decision time and post-decision confidence was higher when the prior probability that the suspect is the perpetrator was high compared to when the prior probability that the suspect is the perpetrator was low. The frequent use of showups in practice emphasizes the importance of these findings for court proceedings. Overall, these findings support the idea that courts should have most trust in showup identifications that were made fast and confidently, and least in showup identifications that were made slowly and with low confidence.

Receiver operating characteristic (ROC) analysis was introduced to the field of eyewitness identification 5 years ago. Since that time, it has been both influential and controversial, and the debate has raised an issue about measuring discriminability that is rarely considered. The issue concerns the distinction between empirical discriminability (measured by area under the ROC curve) vs. underlying/theoretical discriminability (measured by d' or variants of it). Under most circumstances, the two measures will agree about a difference between two conditions in terms of discriminability. However, it is possible for them to disagree, and that fact can lead to confusion about which condition actually yields higher discriminability. For example, if the two conditions have implications for real-world practice (e.g., a comparison of competing lineup formats), should a policymaker rely on the area-under-the-curve measure or the theory-based measure? Here, we illustrate the fact that a given empirical ROC yields as many underlying discriminability measures as there are theories that one is willing to take seriously. No matter which theory is correct, for practical purposes, the singular area-under-the-curve measure best identifies the diagnostically superior procedure. For that reason, area under the ROC curve informs policy in a way that underlying theoretical discriminability never can. At the same time, theoretical measures of discriminability are equally important, but for a different reason. Without an adequate theoretical understanding of the relevant task, the field will be in no position to enhance empirical discriminability., Competing Interests: Not applicableNot applicableThe authors declare that they have no competing interests.

Discrimination accuracy is usually higher for same- than for cross-race faces, a phenomenon known as the cross-race effect (CRE). According to prior research, the CRE occurs because memories for same- and cross-race faces rely on qualitatively different processes. However, according to a continuous dual-process model of recognition memory, memories that rely on qualitatively different processes do not differ in recognition accuracy when confidence is equated. Thus, although there are differences in overall same- and cross-race discrimination accuracy, confidence-specific accuracy (i.e., recognition accuracy at a particular level of confidence) may not differ. We analysed datasets from four recognition memory studies on same- and cross-race faces to test this hypothesis. Confidence ratings reliably predicted recognition accuracy when performance was above chance levels (Experiments 1, 2, and 3) but not when performance was at chance levels (Experiment 4). Furthermore, at each level of confidence, confidence-specific accuracy for same- and cross-race faces did not significantly differ when overall performance was above chance levels (Experiments 1, 2, and 3) but significantly differed when overall performance was at chance levels (Experiment 4). Thus, under certain conditions, high-confidence same-race and cross-race identifications may be equally reliable.

The U.S. legal system increasingly accepts the idea that the confidence expressed by an eyewitness who identified a suspect from a lineup provides little information as to the accuracy of that identification. There was a time when this pessimistic assessment was entirely reasonable because of the questionable eyewitness-identification procedures that police commonly employed. However, after more than 30 years of eyewitness-identification research, our understanding of how to properly conduct a lineup has evolved considerably, and the time seems ripe to ask how eyewitness confidence informs accuracy under more pristine testing conditions (e.g., initial, uncontaminated memory tests using fair lineups, with no lineup administrator influence, and with an immediate confidence statement). Under those conditions, mock-crime studies and police department field studies have consistently shown that, for adults, (a) confidence and accuracy are strongly related and (b) high-confidence suspect identifications are remarkably accurate. However, when certain non-pristine testing conditions prevail (e.g., when unfair lineups are used), the accuracy of even a high-confidence suspect ID is seriously compromised. Unfortunately, some jurisdictions have not yet made reforms that would create pristine testing conditions and, hence, our conclusions about the reliability of high-confidence identifications cannot yet be applied to those jurisdictions. However, understanding the information value of eyewitness confidence under pristine testing conditions can help the criminal justice system to simultaneously achieve both of its main objectives: to exonerate the innocent (by better appreciating that initial, low-confidence suspect identifications are error prone) and to convict the guilty (by better appreciating that initial, high-confidence suspect identifications are surprisingly accurate under proper testing conditions).

Middle-aged and older adults are frequently victims and witnesses of crime, but knowledge of how identification performance changes over the adult life span is sparse. The authors asked young (18-30 years), middle-aged (31-59 years), and older (60-95 years) adults (N = 2,670) to watch a video of a mock crime and to attempt to identify the culprit from a fair lineup (in which all of the lineup members matched the appearance of the suspect) or an unfair lineup (in which the suspect stood out). They also asked subjects to provide confidence ratings for their identification decisions. To examine identification performance, the authors used a standard response-type analysis, receiver operating characteristic analysis, and signal-detection process modeling. The results revealed that, in fair lineups, aging was associated with a genuine decline in recognition ability-discriminability-and not an increased willingness to choose. Perhaps most strikingly, middle-aged and older adults were generally effective at regulating their confidence judgments to reflect the likely accuracy of their suspect identification decisions. Model-fitting confirmed that the older adults spread their decision criteria such that identifications made with high confidence were likely to be highly accurate, despite the substantial decline in discriminability with age. In unfair lineups, ability to discriminate between innocent and guilty suspects was poor in all age groups. The research enhances theoretical understanding of the ways in which identification behavior changes with age, and has important practical implications for how legal decision-makers should interpret identifications made by middle-aged and older eyewitnesses. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)

The hippocampus is important for autobiographical memory, but its role is unclear. In the study, patients with hippocampal damage and controls were taken on a 25-min walk on the University of California, San Diego, campus during which 11 planned events occurred. Memory was tested directly after the walk. In addition, a second group of controls took the same walk and were tested after 1 mo. Patients with hippocampal damage remembered fewer details than controls tested directly after the walk but remembered a similar number of details as controls tested after 1 mo. Notably, the details that were reported by patients had the characteristics of episodic recollection and included references to particular places and events. Patients exhibited no special difficulty remembering spatial details in comparison with nonspatial details. Last, whereas both control groups tended to recall the events of the walk in chronological order, the order in which patients recalled the events was unrelated to the order in which they occurred. The findings illuminate the role of the hippocampus in autobiographical memory and in the spatial and nonspatial aspects of episodic recollection., Competing Interests: The authors declare no conflict of interest.

In two experiments, patients with damage to the medial temporal lobe (MTL) and healthy controls produced detailed autobiographical narratives as they remembered past events (recent and remote) and imagined future events (near and distant). All recent events occurred after the onset of memory impairment. The first experiment aimed to replicate the methods of Race et al. [Race E, Keane MM, Verfaellie M (2011) J Neurosci 31(28):10262-10269]. Transcripts from that study were kindly made available for independent analysis, which largely reproduced the findings from that study. Our patients produced marginally fewer episodic details than controls. Patients from the earlier study were more impaired than our patients. Patients in both groups had difficulty in returning to their narratives after going on tangents, suggesting that anterograde memory impairment may have interfered with narrative construction. In experiment 2, the experimenter used supportive questioning to help keep participants on task and reduce the burden on anterograde memory. This procedure increased the number of details produced by all participants and rescued the performance of our patients for the distant past. Neither of the two patient groups had any special difficulty in producing spatial details. The findings suggest that constructing narratives about the remote past and the future does not depend on MTL structures, except to the extent that anterograde amnesia affects performance. The results further suggest that different findings about the status of autobiographical memory likely depend on differences in the location and extent of brain damage in different patient groups., Competing Interests: In 2013, Dr. Kirwan kindly administered some tests to two patients he had access to. Subsequently, he was a middle author on the resulting PNAS paper [Smith CN, et al. (2014) When recognition memory is independent of hippocampal function. Proc Natl Acad Sci 111(27):9935–9940]. The authors do not regard this as a conflict of interest, as Dr. Kirwan had no part in the planning, interpretation, or writing, and did not participate in any discussions about the project.

Laboratory-based mock crime studies have often been interpreted to mean that (i) eyewitness confidence in an identification made from a lineup is a weak indicator of accuracy and (ii) sequential lineups are diagnostically superior to traditional simultaneous lineups. Largely as a result, juries are increasingly encouraged to disregard eyewitness confidence, and up to 30% of law enforcement agencies in the United States have adopted the sequential procedure. We conducted a field study of actual eyewitnesses who were assigned to simultaneous or sequential photo lineups in the Houston Police Department over a 1-y period. Identifications were made using a three-point confidence scale, and a signal detection model was used to analyze and interpret the results. Our findings suggest that (i) confidence in an eyewitness identification from a fair lineup is a highly reliable indicator of accuracy and (ii) if there is any difference in diagnostic accuracy between the two lineup formats, it likely favors the simultaneous procedure.

Eyewitness memory is widely believed to be unreliable because (a) high-confidence eyewitness misidentifications played a role in over 70% of the now more than 300 DNA exonerations of wrongfully convicted men and women, (b) forensically relevant laboratory studies have often reported a weak relationship between eyewitness confidence and accuracy, and (c) memory is sufficiently malleable that, not infrequently, people (including eyewitnesses) can be led to remember events differently from the way the events actually happened. In light of such evidence, many researchers agree that confidence statements made by eyewitnesses in a court of law (in particular, the high confidence they often express at trial) should be discounted, if not disregarded altogether. But what about confidence statements made by eyewitnesses at the time of the initial identification (e.g., from a lineup), before there is much opportunity for memory contamination to occur? A considerable body of recent empirical work suggests that confidence may be a highly reliable indicator of accuracy at that time, which fits with longstanding theoretical models of recognition memory. Counterintuitively, an appreciation of this fact could do more to protect innocent defendants from being wrongfully convicted than any other eyewitness identification reform that has been proposed to date., ((PsycINFO Database Record (c) 2015 APA, all rights reserved).)

Conscious memory for a new experience is initially dependent on information stored in both the hippocampus and neocortex. Systems consolidation is the process by which the hippocampus guides the reorganization of the information stored in the neocortex such that it eventually becomes independent of the hippocampus. Early evidence for systems consolidation was provided by studies of retrograde amnesia, which found that damage to the hippocampus-impaired memories formed in the recent past, but typically spared memories formed in the more remote past. Systems consolidation has been found to occur for both episodic and semantic memories and for both spatial and nonspatial memories, although empirical inconsistencies and theoretical disagreements remain about these issues. Recent work has begun to characterize the neural mechanisms that underlie the dialogue between the hippocampus and neocortex (e.g., "neural replay," which occurs during sharp wave ripple activity). New work has also identified variables, such as the amount of preexisting knowledge, that affect the rate of consolidation. The increasing use of molecular genetic tools (e.g., optogenetics) can be expected to further improve understanding of the neural mechanisms underlying consolidation., (Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.)