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Find video protocols related to scientific articles indexed in Pubmed.
Individual differences in category learning: Memorization versus rule abstraction.
Mem Cognit
PUBLISHED: 10-16-2014
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Although individual differences in category-learning tasks have been explored, the observed differences have tended to represent different instantiations of general processes (e.g., learners rely upon different cues to develop a rule) and their consequent representations. Additionally, studies have focused largely on participants' categorizations of transfer items to determine the representations that they formed. In the present studies, we used a convergent-measures approach to examine participants' categorizations of transfer items in addition to their self-reported learning orientations and response times on transfer items, and in doing so, we garnered evidence that qualitatively distinct approaches in explicit strategies for category learning (i.e., memorization vs. abstracting an articulable rule) and consequent representations might emerge in a single task. Participants categorized instances that followed a categorization rule (in Study 1, we used a relational rule; in Study 2, an additional task with a single-feature rule). Critically, for both tasks, some transfer items differed from trained instances on only one attribute (but otherwise were perceptually similar), rendering the item a member of the opposing category on the basis of the rule (i.e., termed ambiguous items). Some learners categorized ambiguous items on the basis of perceptual similarity, whereas others categorized them on the basis of an abstracted rule. Self-reported learning orientation (i.e., memorization vs. rule abstraction) predicted categorizations and response times on transfer items. Differences in learning orientations were not associated with performance on other cognitive measures (i.e., working memory capacity and Raven's Advanced Progressive Matrices). This work suggests that individuals may have different predispositions toward memorization versus rule abstraction in a single categorization task.
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Effects of cognitive training with and without aerobic exercise on cognitively demanding everyday activities.
Psychol Aging
PUBLISHED: 09-23-2014
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We investigated the potential benefits of a novel cognitive-training protocol and an aerobic exercise intervention, both individually and in concert, on older adults' performances in laboratory simulations of select real-world tasks. The cognitive training focused on a range of cognitive processes, including attentional coordination, prospective memory, and retrospective-memory retrieval, processes that are likely involved in many everyday tasks, and that decline with age. Primary outcome measures were 3 laboratory tasks that simulated everyday activities: Cooking Breakfast, Virtual Week, and Memory for Health Information. Two months of cognitive training improved older adults' performance on prospective-memory tasks embedded in Virtual Week. Cognitive training, either alone or in combination with 6 months of aerobic exercise, did not significantly improve Cooking Breakfast or Memory for Health Information. Although gains in aerobic power were comparable with previous reports, aerobic exercise did not produce improvements for the primary outcome measures. Discussion focuses on the possibility that cognitive-training programs that include explicit strategy instruction and varied practice contexts may confer gains to older adults for performance on cognitively challenging everyday tasks.
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Metamemory monitoring and control following retrieval practice for text.
Mem Cognit
PUBLISHED: 08-19-2014
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Test-taking is assumed to help learners diagnose what they do and do not know, and by so doing improve the effectiveness of their subsequent study. Previous work has examined metamemory monitoring (e.g., predictions of future performance) and control (e.g., restudy decisions) following testing or retrieval practice with relatively simple materials (e.g., word pairs). There is reason to believe, however, that such monitoring and control decisions might be more difficult with text materials, even after retrieval practice, owing perhaps to difficulty in accurately assessing one's performance on the retrieval-practice test. In two experiments, participants read texts about world regions, then engaged in retrieval practice or rereading of the information in those texts, made estimates about future performance, and then received an opportunity to restudy the texts before taking a final recall test, with self-paced restudy enabling an examination of control processes. Memory predictions were more accurate in the retrieval-practice than in the rereading condition, and learners in both conditions allocated restudy time on the basis of their predictions. Additionally, restudy provided a greater benefit following retrieval practice than following rereading. The present study has implications for how students can use retrieval practice with text to foster subsequent learning.
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Relational and item-specific influences on generate-recognize processes in recall.
Mem Cognit
PUBLISHED: 01-16-2014
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The generate-recognize model and the relational-item-specific distinction are two approaches to explaining recall. In this study, we consider the two approaches in concert. Following Jacoby and Hollingshead (Journal of Memory and Language 29:433-454, 1990), we implemented a production task and a recognition task following production (1) to evaluate whether generation and recognition components were evident in cued recall and (2) to gauge the effects of relational and item-specific processing on these components. An encoding task designed to augment item-specific processing (anagram-transposition) produced a benefit on the recognition component (Experiments 1-3) but no significant benefit on the generation component (Experiments 1-3), in the context of a significant benefit to cued recall. By contrast, an encoding task designed to augment relational processing (category-sorting) did produce a benefit on the generation component (Experiment 3). These results converge on the idea that in recall, item-specific processing impacts a recognition component, whereas relational processing impacts a generation component.
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Neural mechanisms of time-based prospective memory: evidence for transient monitoring.
PLoS ONE
PUBLISHED: 01-01-2014
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In daily life, we often need to remember to perform an action after, or at, a specific period of time (e.g., take pizza out of oven in 15 minutes). Surprisingly, little is known about the neural mechanisms that support this form of memory, termed time-based prospective memory (PM). Here we pioneer an fMRI paradigm that enables examination of both sustained and transient processes engaged during time-based PM. Participants were scanned while performing a demanding on-going task (n-back working memory), with and without an additional time-based PM demand. During the PM condition participants could access a hidden clock with a specific button-press response, while in the control condition, pseudo-clocks randomly appeared and were removed via the same response. Analyses tested for sustained activation associated with the PM condition, and also transient activation associated with clock-checks and the PM target response. Contrary to prior findings with event-based PM (i.e., remembering to perform a future action when a specific event occurs), no sustained PM-related activity was observed in anterior prefrontal cortex (aPFC) or elsewhere in the brain; instead, transient clock-related activity was observed in this region. Critically, the activation was anticipatory, increasing before clock-check responses. Anticipatory activity prior to the PM target response was weaker in aPFC, but strong in pre-Supplementary Motor Area (pre-SMA; relative to clock-check responses), suggesting a functional double dissociation related to volitional decision-making. Together, the results suggest that aPFC-activity dynamics during time-based PM reflect a distinct transient monitoring process, enabling integration of the PM intention with current temporal information to facilitate scheduling of upcoming PM-related actions.
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Both Multiple-Choice and Short-Answer Quizzes Enhance Later Exam Performance in Middle and High School Classes.
J Exp Psychol Appl
PUBLISHED: 11-25-2013
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Practicing retrieval of recently studied information enhances the likelihood of the learner retrieving that information in the future. We examined whether short-answer and multiple-choice classroom quizzing could enhance retention of information on classroom exams taken for a grade. In seventh-grade science and high school history classes, students took intermittent quizzes (short-answer or multiple-choice, both with correct-answer feedback) on some information, whereas other information was not initially quizzed but received equivalent coverage in all other classroom activities. On the unit exams and on an end-of-semester exam, students performed better for information that had been quizzed than that not quizzed. An unanticipated and key finding is that the format of the quiz (multiple-choice or short-answer) did not need to match the format of the criterial test (e.g., unit exam) for this benefit to emerge. Further, intermittent quizzing cannot be attributed to intermittent reexposure to the target facts: A restudy condition produced less enhancement of later test performance than did quizzing with feedback. Frequent classroom quizzing with feedback improves student learning and retention, and multiple-choice quizzing is as effective as short-answer quizzing for this purpose. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
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Discrepancy-plus-search processes in prospective memory retrieval.
Mem Cognit
PUBLISHED: 08-15-2013
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In the present study, we investigated the processes underlying prospective memory (PM) retrieval, focusing specifically on two possible spontaneous processes: discrepancy-plus-search and familiarity. Discrepancy was elicited by orthogonally manipulating the processing difficulties of the PM targets and the nontargets. Participants performed a PM task while solving anagrams with two levels of difficulty (easy or difficult). Assuming that the ease of processing easy anagrams would heighten a sense of familiarity, the familiarity view predicted better PM performance with easy anagrams as the PM targets. In contrast, the discrepancy-plus-search view predicted higher PM performance for the PM targets that were anagrams whose difficulty level mismatched that of the surrounding nontargets, as compared to PM targets whose difficulty matched that of the surrounding nontargets. This prediction was based on the idea that mismatching rather than matching difficulty levels would create discrepancy, thereby signaling significance for the target. Participants were more likely to perform the PM task for PM targets that were discrepant, supporting the discrepancy-plus-search view.
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Dissociable neural routes to successful prospective memory.
Psychol Sci
PUBLISHED: 08-01-2013
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Identifying the processes by which people remember to execute an intention at an appropriate moment (prospective memory) remains a fundamental theoretical challenge. According to one account, top-down attentional control is required to maintain activation of the intention, initiate intention retrieval, or support monitoring. A diverging account suggests that bottom-up, spontaneous retrieval can be triggered by cues that have been associated with the intention and that sustained attentional processes are not required. We used a specialized experimental design and functional MRI methods to selectively marshal and identify each process. Results revealed a clear dissociation. One prospective-memory task recruited sustained activity in attentional-control areas, such as the anterior prefrontal cortex; the other engaged purely transient activity in parietal and ventral brain regions associated with attentional capture, target detection, and episodic retrieval. These patterns provide critical evidence that there are two neural routes to prospective memory, with each route emerging under different circumstances.
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The Dynamic Multiprocess Framework: evidence from prospective memory with contextual variability.
Cogn Psychol
PUBLISHED: 06-19-2013
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The ability to remember to execute delayed intentions is referred to as prospective memory. Previous theoretical and empirical work has focused on isolating whether a particular prospective memory task is supported either by effortful monitoring processes or by cue-driven spontaneous processes. In the present work, we advance the Dynamic Multiprocess Framework, which contends that both monitoring and spontaneous retrieval may be utilized dynamically to support prospective remembering. To capture the dynamic interplay between monitoring and spontaneous retrieval, we had participants perform many ongoing tasks and told them that their prospective memory cue may occur in any context. Following either a 20-min or a 12-h retention interval, the prospective memory cues were presented infrequently across three separate ongoing tasks. The monitoring patterns (measured as ongoing task cost relative to a between-subjects control condition) were consistent and robust across the three contexts. There was no evidence for monitoring prior to the initial prospective memory cue; however, individuals who successfully spontaneously retrieved the prospective memory intention, thereby realizing that prospective memory cues could be expected within that context, subsequently monitored. These data support the Dynamic Multiprocess Framework, which contends that individuals will engage monitoring when prospective memory cues are expected, disengage monitoring when cues are not expected, and that when monitoring is disengaged, a probabilistic spontaneous retrieval mechanism can support prospective remembering.
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Individual Differences in Learning and Transfer: Stable Tendencies for Learning Exemplars Versus Abstracting Rules.
J Exp Psychol Gen
PUBLISHED: 06-10-2013
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We hypothesize that during training some learners may focus on acquiring the particular exemplars and responses associated with the exemplars (termed exemplar learners), whereas other learners attempt to abstract underlying regularities reflected in the particular exemplars linked to an appropriate response (termed rule learners). Supporting this distinction, after training (on a function-learning task), participants displayed an extrapolation profile reflecting either acquisition of the trained cue-criterion associations (exemplar learners) or abstraction of the function rule (rule learners; Studies 1a and 1b). Further, working memory capacity (measured by operation span [Ospan]) was associated with the tendency to rely on rule versus exemplar processes. Studies 1c and 2 examined the persistence of these learning tendencies on several categorization tasks. Study 1c showed that rule learners were more likely than exemplar learners (indexed a priori by extrapolation profiles) to resist using idiosyncratic features (exemplar similarity) in generalization (transfer) of the trained category. Study 2 showed that the rule learners but not the exemplar learners performed well on a novel categorization task (transfer) after training on an abstract coherent category. These patterns suggest that in complex conceptual tasks, (a) individuals tend to either focus on exemplars during learning or on extracting some abstraction of the concept, (b) this tendency might be a relatively stable characteristic of the individual, and (c) transfer patterns are determined by that tendency. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
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The bizarreness effect: evidence for the critical influence of retrieval processes.
Mem Cognit
PUBLISHED: 06-06-2013
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People show better memory for bizarre sentences relative to common sentences, a finding referred to as the bizarrness effect. Interestingly, this effect is typically only obtained using a mixed-list design, in which participants study common and bizarre sentences in the same list. This bizarreness effect in mixed-list designs has been explained as the result of both enhanced encoding processes and efficient retrieval processes. The present experiment was designed to isolate the unique contributions of the retrieval context to the bizarreness effect. Participants studied common sentences in one room under one set of instructions, and bizarre sentences in another room under another set of instructions. At test, participants recalled the common and bizarre sentences either together or separately. The results showed that the bizarreness effect was only obtained when participants recalled the common and bizarre items together; no bizarreness advantage emerged when participants were required to recall the common and bizarre items separately. These results suggest that differential encoding processes are not necessary for explaining the bizarreness effect in memory. Rather, retrieval of the mixed-list context appears to be critical for obtaining the effect.
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Effects of spaced versus massed training in function learning.
J Exp Psychol Learn Mem Cogn
PUBLISHED: 04-08-2013
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A robust finding in the literature is that spacing material leads to better retention than massing; however, the benefit of spacing for concept learning is less clear. When items are massed, it may help the learner to discover the relationship between instances, leading to better abstraction of the underlying concept. Two experiments addressed this question through a typical function learning task in which subjects were trained via presentations of input points (cue values) for which output responses (criterion values) were required. Subjects were trained either using spaced points, strategically massed points (points were paired in training such that they occurred on the same side of the underlying V-shaped function), or randomly massed points (points were randomly paired during training). All subjects were then tested on repeated training points, new (interpolation) points within the training range, and extrapolation points that fell outside the training range. Spacing led to superior interpolation and extrapolation performance, with random massing leading to the worst performance on all test trial types. These results suggest that, at least for function concepts, massed training is not superior to spaced training for concept learning.
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Prospective memory in Parkinson disease during a virtual week: effects of both prospective and retrospective demands.
Neuropsychology
PUBLISHED: 03-27-2013
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This study investigated the effect of Parkinsons disease (PD) on event-based prospective memory tasks with varying demand on (1) the amount of strategic attentional monitoring required for intention retrieval (prospective component), and (2) the retrospective memory processes required to remember the contents of the intention or the entire constellation of prospective memory tasks.
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Evidence for a detrimental relationship between hypertension history, prospective memory, and prefrontal cortex white matter in cognitively normal older adults.
Cogn Affect Behav Neurosci
PUBLISHED: 02-08-2013
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Hypertension affects many older adults and is associated with impaired neural and cognitive functioning. We investigated whether a history of hypertension was associated with impairments to prospective memory, which refers to the ability to remember to perform delayed intentions, such as remembering to take medication. Thirty-two cognitively normal older adult participants with or without a history of hypertension (self-reported) performed two laboratory prospective memory tasks, one that relied more strongly on executive control (nonfocal prospective memory) and one that relied more strongly on spontaneous memory retrieval processes (focal prospective memory). We observed hypertension-related impairments for nonfocal, but not focal, prospective memory. To complement our behavioral approach, we conducted a retrospective analysis of available structural magnetic resonance imaging data. Lower white matter volume estimates in the anterior prefrontal cortex were associated with lower nonfocal prospective memory and with a history of hypertension. A history of hypertension may be associated with worsened executive control and lower prefrontal white matter volume. The translational implication is that individuals who must remember to take antihypertensive medications and to monitor their blood pressure at home may be impaired in the executive control process that helps to support these prospective memory behaviors.
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Strengthening encoding via implementation intention formation increases prospective memory commission errors.
Psychon Bull Rev
PUBLISHED: 01-29-2013
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Prospective memory refers to the ability to remember to execute future intentions (e.g., taking medication with dinner). Although most prior research on prospective memory errors has focused on omission errors (i.e., failures to perform an intention in response to a target cue), there has been a recent surge in research on commission errors, the erroneous performance of a finished intention. Existing studies have examined factors at retrieval that lead to commission errors; the present study extends this research by investigating the impact of encoding strength. We found that relative to standard encoding, implementation intention encoding doubled the risk of commission errors in our laboratory paradigm for both young and older adults. This novel finding demonstrates the impact of encoding strength on commission errors and documents the potential challenges of deactivating the effects of implementation intentions upon completion of a prospective memory task.
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Resource depletion does not influence prospective memory in college students.
Conscious Cogn
PUBLISHED: 01-02-2013
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This paper reports an experiment designed to investigate the potential influence of prior acts of self-control on subsequent prospective memory performance. College undergraduates (n=146) performed either a cognitively depleting initial task (e.g., mostly incongruent Stroop task) or a less resource-consuming version of that task (e.g., all congruent Stroop task). Subsequently, participants completed a prospective memory task that required attentionally demanding monitoring processes. The results demonstrated that prior acts of self-control do not impair the ability to execute a future intention in college-aged adults. We conceptually replicated these results in three additional depletion and prospective memory experiments. This research extends a growing number of studies demonstrating the boundary conditions of the resource depletion effect in cognitive tasks.
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Test-enhanced learning in the classroom: long-term improvements from quizzing.
J Exp Psychol Appl
PUBLISHED: 11-14-2011
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Three experiments examined whether quizzing promotes learning and retention of material from a social studies course with sixth grade students from a suburban middle school. The material used in the experiments was the course material students were to learn and some of the dependent measures were the actual tests on which students received grades. In within-subject designs, students received three low-stakes multiple-choice quizzes in Experiments 1 and 2 and performance on quizzed items was compared to that on items that were presented twice (Experiment 2) or items that were not presented on the initial quizzes (Experiments 1 and 2). We found that students performance on both chapter exams and semester exams improved following quizzing relative to either not being quizzed or relative to the twice-presented items. In Experiment 3, students were given one multiple-choice quiz in class and encouraged to quiz themselves outside of class using a Web-based system. The assessment in this experiment was a short answer test in which students had to produce answers, but we also used multiple-choice tests. Once again, we found that quizzing of material produced a positive effect on chapter and semester exams. These results show the robustness of retrieval practice via testing as a learning mechanism in a classroom setting using the subject matter of the course and (in most cases) the tests on which students received grades as the dependent measures. Our results add to a growing body of evidence that retrieval practice in the classroom can boost academic performance.
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Whoops, I did it again: commission errors in prospective memory.
Psychol Aging
PUBLISHED: 11-14-2011
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Prospective memory research almost exclusively examines remembering to execute an intention, but the ability to forget completed intentions may be similarly important. We had younger and older adults perform a prospective memory task (press Q when you see corn or dancer) and then told them that the intention was completed. Participants later performed a lexical-decision task (Phase 2) in which the prospective memory cues reappeared. Initial prospective memory performance was similar between age groups, but older adults were more likely than younger adults to press Q during Phase 2 (i.e., commission errors). This study provides the first experimental demonstration of event-based prospective memory commission errors after all prospective memory tasks are finished and identifies multiple factors that increase risk for commission errors.
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A characterization of individual differences in prospective memory monitoring using the Complex Ongoing Serial Task.
J Exp Psychol Gen
PUBLISHED: 11-07-2011
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Prospective memory--remembering to retrieve and execute future goals--is essential to daily life. Prospective remembering is often achieved through effortful monitoring; however, potential individual differences in monitoring patterns have not been characterized. We propose 3 candidate models to characterize the individual differences present in prospective memory monitoring: attentional focus, secondary memory retrieval, and information thresholding. Two experiments using a novel paradigm, the Complex Ongoing Serial Task (COST), investigated the resource allocation patterns underlying individual differences in monitoring. Individuals exhibited differential resource allocation patterns, and the differences remained relatively stable across experimental sessions. Resource allocation patterns associated with information thresholding (high prospective memory, preserved ongoing task performance) and attentional focus (high prospective memory, inefficient ongoing task performance) were superior to secondary memory retrieval (low prospective memory, very inefficient ongoing task performance). Importantly, personality (openness, prevention focus) and cognitive (primary, working, and secondary memory) individual differences influenced monitoring patterns. This research represents the first explicit attempt to elucidate individual differences in prospective memory monitoring patterns.
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A sham drug improves a demanding prospective memory task.
Memory
PUBLISHED: 09-17-2011
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Every day, people rely on prospective memory--our ability to remember to perform a future action--to carry out myriad tasks. We examined how a sham cognitive enhancing drug might improve peoples performance on a prospective memory task. We gave some people (but not others) the sham drug, and asked everyone to perform a high-effort prospective memory task. People who received the sham drug performed better on the prospective memory task. They also took longer to perform their ongoing task, suggesting that they increased their effortful monitoring. These results fit with research showing that suggestions can lead people to increase cognitive effort and increase memory performance.
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Revealing list-level control in the Stroop task by uncovering its benefits and a cost.
J Exp Psychol Hum Percept Perform
PUBLISHED: 07-20-2011
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Interference is reduced in mostly incongruent relative to mostly congruent lists. Classic accounts of this list-wide proportion congruence effect assume that list-level control processes strategically modulate word reading. Contemporary accounts posit that reliance on the word is modulated poststimulus onset by item-specific information (e.g., proportion congruency of the word). To adjudicate between these accounts, we used novel designs featuring neutral trials. In two experiments, we showed that the list-wide proportion congruence effect is accompanied by a change in neutral trial color-naming performance. Because neutral words have no item-specific bias, this pattern can be attributed to list-level control. Additionally, we showed that list-level attenuation of word reading led to a cost to performance on a secondary prospective memory task but only when that task required processing of the irrelevant, neutral word. These findings indicate that the list-wide proportion congruence effect at least partially reflects list-level control and challenge purely item-specific accounts of this effect.
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Effects of testing on learning of functions.
Psychon Bull Rev
PUBLISHED: 06-02-2011
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Is learning of a complex functional relationship enhanced by trying to predict what output will go with a given input, as compared to studying an input-output pair? We examined learning of a bilinear function and transfer to new items outside the trained range. Subjects either saw the input-output pairs (study-only condition) or attempted to guess the output and then saw the pair (test/study condition). The total study times were equated, and motivation was enhanced with a monetary bonus. Performance was markedly better for the test/study condition, both within the trained range and in the transfer test. This benefit of testing during training was observed on a criterial test administered shortly after training. Testing has long been shown to enhance the explicit learning and retention of verbal material; our present findings reveal a novel domain for which testing can also be advantageous-that is, function learning.
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Structural correlates of prospective memory.
Neuropsychologia
PUBLISHED: 05-18-2011
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Prospective memory (PM) includes the encoding and maintenance of an intention, and the retrieval and execution of this intention at the proper moment in the future. The present study expands upon previous behavioral, electrophysiological, and functional work by examining the association between grey matter volume and PM. Estimates of grey matter volume in theoretically relevant regions of interest (prefrontal, parietal, and medial temporal) were obtained in conjunction with performance on two PM tasks in a sample of 39 cognitively normal and very mildly demented older adults. The first PM task, termed focal in the literature, is supported by spontaneous retrieval of the PM intention whereas the second, termed non-focal, relies on strategic monitoring processes for successful intention retrieval. A positive relationship was observed between medial temporal volume and accuracy on the focal PM task. An examination of medial temporal lobe subregions revealed that this relationship was strongest for the hippocampus, which is considered to support spontaneous memory retrieval. There were no significant structure-behavior associations for the non-focal PM task. These novel results confirm a relationship between behavior and underlying brain structure proposed by the multiprocess theory of PM, and extend findings on cognitive correlates of medial temporal lobe integrity.
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Dissociative effects of orthographic distinctiveness in pure and mixed lists: an item-order account.
Mem Cognit
PUBLISHED: 05-18-2011
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We apply the item-order theory of list composition effects in free recall to the orthographic distinctiveness effect. The item-order account assumes that orthographically distinct items advantage item-specific encoding in both mixed and pure lists, but at the expense of exploiting relational information present in the list. Experiment 1 replicated the typical free recall advantage of orthographically distinct items in mixed lists and the elimination of that advantage in pure lists. Supporting the item-order account, recognition performances indicated that orthographically distinct items received greater item-specific encoding than did orthographically common items in mixed and pure lists (Experiments 1 and 2). Furthermore, order memory (input-output correspondence and sequential contiguity effects) was evident in recall of pure unstructured common lists, but not in recall of unstructured distinct lists (Experiment 1). These combined patterns, although not anticipated by prevailing views, are consistent with an item-order account.
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Prospective memory and aging: preserved spontaneous retrieval, but impaired deactivation, in older adults.
Mem Cognit
PUBLISHED: 05-11-2011
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Prospective remembering is partially supported by cue-driven spontaneous retrieval processes. We investigated spontaneous retrieval processes in younger and older adults by presenting prospective memory target cues during a lexical decision task following instructions that the prospective memory task was finished. Spontaneous retrieval was inferred from slowed lexical decision responses to target cues (i.e., intention interference). When the intention was finished, younger adults efficiently deactivated their intention, but the older adults continued to retrieve their intentions. Levels of inhibitory functioning were negatively associated with intention interference in the older adult group, but not in the younger adult group. These results indicate that normal aging might not compromise spontaneous retrieval processes but that the ability to deactivate completed intentions is impaired.
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Focal and nonfocal prospective memory performance in very mild dementia: a signature decline.
Neuropsychology
PUBLISHED: 03-30-2011
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In a recent study, performance on a certain kind of prospective memory task (PM), labeled focal PM, was sensitive to the very early stages of Alzheimers disease (AD; Duchek, Balota, & Cortese, 2006). This study sought to replicate and extend these findings by investigating both focal and nonfocal PM, as well as possible influences of alleles of the apolipoprotein E (ApoE) gene.
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The age prospective memory paradox: young adults may not give their best outside of the lab.
Dev Psychol
PUBLISHED: 11-10-2010
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Previous research has identified the age prospective memory paradox of age-related declines in laboratory settings in contrast to age benefits in naturalistic settings. Various factors are assumed to account for this paradox, yet empirical evidence on this issue is scarce. In 2 experiments, the present study examined the effect of task setting in a laboratory task and the effect of motivation in a naturalistic task on prospective memory performance in young and older adults. For the laboratory task (Experiment 1, n = 40), we used a board game to simulate a week of daily activities and varied features of the prospective memory task (e.g., task regularity). For the naturalistic task (Experiment 2, n = 80), we instructed participants to try to remember to contact the experimenter repeatedly over the course of 1 week. Results from the laboratory prospective memory tasks indicated significant age-related decline for irregular tasks (p = .006) but not for regular and focal tasks. In addition, in the naturalistic task, the age benefit was eliminated when young adults were motivated by incentives (F < 1). In conclusion, the present results indicate that the variability of age differences in laboratory prospective memory tasks may be due in part to differences in the features of the prospective memory task. Furthermore, increases in motivation to perform the prospective task seem to help remedy prospective memory deficits in young adults in the naturalistic setting.
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Cognitive exertion and subsequent intention execution in older adults.
J Gerontol B Psychol Sci Soc Sci
PUBLISHED: 10-29-2010
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Previous studies have demonstrated that increasing the demands of a prospective memory task is detrimental to older adults performance; however, no studies have investigated how prior cognitive demands influence subsequent prospective memory. The present study sought to address this gap by using a resource depletion paradigm.
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Age and individual differences in prospective memory during a "Virtual Week": the roles of working memory, vigilance, task regularity, and cue focality.
Psychol Aging
PUBLISHED: 09-22-2010
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Young (ages 18-22 years) and older (ages 61-87 years) adults (N = 106) played the Virtual Week board game, which involves simulating common prospective memory (PM) tasks of everyday life (e.g., taking medication), and performed working memory (WM) and vigilance tasks. The Virtual Week game includes regular (repeated) and irregular (nonrepeated) PM tasks with cues that are either more or less focal to other ongoing activities. Age differences in PM were reduced for repeated tasks, and performance improved over the course of the week, suggesting retrieval was more spontaneous or habitual. Correlations with WM within each age group were reduced for PM tasks that had more regular or focal cues. WM (but not vigilance) ability was a strong predictor of irregular PM tasks with less focal cues. Taken together, these results support the hypothesis that habitual and focally cued PM tasks are less demanding of attentional resources (specifically, WM), whereas tasks that are more demanding of controlled attentional processes produce larger age differences, which may be attributable to individual differences in WM.
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The neuropsychology of prospective memory in normal aging: a componential approach.
Neuropsychologia
PUBLISHED: 08-02-2010
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To guide understanding of the neuropsychology of prospective memory and aging, we highlight several components of prospective memory, including planning an intended action, retrieving the action at the appropriate moment, and executing the action. We posit that frontal systems are particularly important for prospective memory tasks that require planning, that require strategic monitoring to detect the appropriate moment for executing the prospective memory intention, or for which execution of the retrieved intention must be delayed briefly. Drawing from a variety of approaches, including neuroimaging (with young adults) and studies examining individual differences relating to frontal functioning, we assemble preliminary evidence that supports this hypothesis. Further, because aging especially disrupts frontal functioning, the above noted prospective memory tasks would thus be expected to display the greatest age-related decline. The available literature confirms this expectation. A second key hypothesis is that some prospective memory tasks--those requiring minimal planning and supporting spontaneous retrieval--do not rely extensively on frontal processes but instead rely on medial-temporal structures for reflexive retrieval. These prospective memory tasks tend to show minimal or no age-related decline. The literature, though sparse with regard to the neuropsychological underpinnings of this kind of prospective memory task, is consistent with the present hypothesis.
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Prospective memory and what costs do not reveal about retrieval processes: A commentary on Smith, Hunt, McVay, and McConnell (2007).
J Exp Psychol Learn Mem Cogn
PUBLISHED: 06-23-2010
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On the basis of consistently finding significant overall costs to the ongoing task with a single salient target event, Smith, Hunt, McVay, and McConnell (2007) concluded that preparatory attentional processes are required for prospective remembering and that spontaneous retrieval does not occur. In this article, we argue that overall costs are not completely informative in terms of specifying the underlying processes mediating prospective memory retrieval, and we suggest more promising approaches for testing for the existence of these processes. We also argue that counterbalancing in a within-subjects design is one of several proper methods for assessing costs.
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Remembering to execute a goal: sleep on it!
Psychol Sci
PUBLISHED: 06-02-2010
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Remembering to execute deferred goals (prospective memory) is a ubiquitous memory challenge, and one that is often not successfully accomplished. Could sleeping after goal encoding promote later execution? We evaluated this possibility by instructing participants to execute a prospective memory goal after a short delay (20 min), a 12-hr wake delay, or a 12-hr sleep delay. Goal execution declined after the 12-hr wake delay relative to the short delay. In contrast, goal execution was relatively preserved after the 12-hr sleep delay relative to the short delay. The sleep-enhanced goal execution was not accompanied by a decline in performance of an ongoing task in which the prospective memory goal was embedded, which suggests that the effect was not a consequence of attentional resources being reallocated from the ongoing task to the prospective memory goal. Our results suggest that consolidation processes active during sleep increase the probability that a goal will be spontaneously retrieved and executed.
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Focal/nonfocal cue effects in prospective memory: monitoring difficulty or different retrieval processes?
J Exp Psychol Learn Mem Cogn
PUBLISHED: 05-05-2010
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We investigated whether focal/nonfocal effects (e.g., Einstein et al., 2005) in prospective memory (PM) are explained by cue differences in monitoring difficulty. In Experiment 1, we show that syllable cues (used in Einstein et al., 2005) are more difficult to monitor for than are word cues; however, initial-letter cues (in words) are similar in monitoring difficulty to word cues (Experiments 2a and 2b). Accordingly, in Experiments 3 and 4, we designated either an initial letter or a particular word as a PM cue in the context of a lexical decision task, a task that presumably directs attention to focal processing of words but not initial letters. We found that the nonfocal condition was more likely than the focal condition to produce costs to the lexical decision task (task interference). Furthermore, when task interference was minimal or absent, focal PM performance remained relatively high, whereas nonfocal PM performance was near floor (Experiment 4). Collectively, these results suggest that qualitatively different retrieval processes can support prospective remembering for focal versus nonfocal cues.
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The relationship between working memory capacity and executive functioning: evidence for a common executive attention construct.
Neuropsychology
PUBLISHED: 03-17-2010
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Attentional control has been conceptualized as executive functioning by neuropsychologists and as working memory capacity by experimental psychologists. We examined the relationship between these constructs using a factor analytic approach in an adult life span sample. Several tests of working memory capacity and executive function were administered to more than 200 subjects between 18 and 90 years of age, along with tests of processing speed and episodic memory. The correlation between working memory capacity and executive functioning constructs was very strong (r = .97), but correlations between these constructs and processing speed were considerably weaker (rs approximately .79). Controlling for working memory capacity and executive function eliminated age effects on episodic memory, and working memory capacity and executive function accounted for variance in episodic memory beyond that accounted for by processing speed. We conclude that tests of working memory capacity and executive function share a common underlying executive attention component that is strongly predictive of higher level cognition.
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Implementation intention encoding does not automatize prospective memory responding.
Mem Cognit
PUBLISHED: 02-23-2010
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An implementation intention encoding, one that specifies the concrete situation that is appropriate for initiating an intended action and links that situational cue to the intended action, has been shown to improve prospective memory. One proposed mechanism is that implementation intentions create automatized prospective remembering. This view anticipates that implementation intentions should prevent prospective memory decline in highly cognitively demanding situations. Contrary to this expectation, although implementation intention encoding enhanced prospective memory (Experiments 1 and 2), implementation-intention encoding did not buffer against significant prospective memory decline in high-cognitive-demand conditions (Experiments 1-3), and in Experiment 3, implementation intention encoding produced lower levels of prospective memory performance than did behavioral practice in the high-cognitive-demand situation. We suggest that although implementation intentions may stimulate a strong associative encoding (between an anticipated environmental cue and an intended action), that encoding does not support a completely automatized prospective memory response.
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Control of cost in prospective memory: evidence for spontaneous retrieval processes.
J Exp Psychol Learn Mem Cogn
PUBLISHED: 01-08-2010
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To examine the processes that support prospective remembering, previous research has often examined whether the presence of a prospective memory task slows overall responding on an ongoing task. Although slowed task performance suggests that monitoring is present, this method does not clearly establish whether monitoring is functionally related to prospective memory performance. According to the multiprocess theory (McDaniel & Einstein, 2000), monitoring should be necessary to prospective memory performance with nonfocal cues but not with focal cues. To test this hypothesis, we varied monitoring by presenting items that were related (or unrelated) to the prospective memory task proximal to target events. Notably, whereas monitoring proximal to target events led to a large increase in nonfocal prospective memory performance, focal prospective remembering was high in the absence of monitoring, and monitoring in this condition provided no additional benefits. These results suggest that when monitoring is absent, spontaneous retrieval processes can support focal prospective remembering. (PsycINFO Database Record (c) 2009 APA, all rights reserved).
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Aging reduces veridical remembering but increases false remembering: neuropsychological test correlates of remember-know judgments.
Neuropsychologia
PUBLISHED: 09-16-2009
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In 1985 Tulving introduced the remember-know procedure, whereby subjects are asked to distinguish between memories that involve retrieval of contextual details (remembering) and memories that do not (knowing). Several studies have been reported showing age-related declines in remember hits, which has typically been interpreted as supporting dual-process theories of cognitive aging that align remembering with a recollection process and knowing with a familiarity process. Less attention has been paid to remember false alarms, or their relation to age. We reviewed the literature examining aging and remember/know judgments and show that age-related increases in remember false alarms, i.e., false remembering, are as reliable as age-related decreases in remember hits, i.e., veridical remembering. Moreover, a meta-analysis showed that the age effect size for remember hits and false alarms are similar, and larger than age effects on know hits and false alarms. We also show that the neuropsychological correlates of remember hits and false alarms differ. Neuropsychological tests of medial-temporal lobe functioning were related to remember hits, but tests of frontal-lobe functioning and age were not. By contrast, age and frontal-lobe functioning predicted unique variance in remember false alarms, but MTL functioning did not. We discuss various explanations for these findings and conclude that any comprehensive explanation of recollective experience will need to account for the processes underlying both remember hits and false alarms.
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The influence of distinctive processing manipulations on older adults false memory.
Neuropsychol Dev Cogn B Aging Neuropsychol Cogn
PUBLISHED: 07-29-2009
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Covertly generating item-specific characteristics for each studied word from DRM (Deese-Roediger-McDermott) lists decreases false memory in young adults. The typical interpretation of this finding is that item-specific characteristics act as additional unique source information bound to each studied item at encoding, and at retrieval young adults can use the absence of this type of information to reject non-presented associated words that might otherwise be falsely remembered. In two experiments, we examined whether healthy older adults could use this strategy to reduce their false memories in the DRM paradigm. In Experiment 1, low frontal lobe functioning was associated with increased false memory in the item-specific strategy condition. Experiment 2 found more memory intrusions under item-specific encoding and the same amount of false memory in auditory and visual presentation conditions, i.e., no modality effect, even with 8 s of encoding time. Both findings are consistent with impaired distinctive processing by older adults.
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Repetition errors in habitual prospective memory: elimination of age differences via complex actions or appropriate resource allocation.
Neuropsychol Dev Cogn B Aging Neuropsychol Cogn
PUBLISHED: 05-28-2009
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A challenge in habitual prospective memory tasks (e.g., taking medication) is remembering whether or not one has already performed the action. Einstein, McDaniel, Smith, and Shaw (1998, Psychological Science, 9, 284) showed that older adults were more likely to incorrectly repeat an action on habitual prospective memory tasks. Extending this research, we (a) biased participants either toward repetition or omission errors, (b) investigated whether performing a more complicated motor action can reduce repetition errors for older adults, and (c) examined participants resource allocation to the prospective memory task. Older adults committed more repetition errors than younger adults regardless of biasing instructions when ongoing task demands were challenging (Experiment 1). Performing the more complex motor action, however, reduced repetition errors for older adults. Further, when the ongoing task was less demanding, older adults repetition errors declined to levels of younger adults (Experiment 2). Consistent with this finding, the resource allocation profiles suggested that older participants were monitoring their output (prospective memory execution) in each trial block.
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Evidence for spontaneous retrieval of suspended but not finished prospective memories.
Mem Cognit
PUBLISHED: 05-23-2009
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McDaniel and Einstein (2007) argued that prospective memories can be retrieved through spontaneous retrieval processes stimulated by the presence of a target cue. To test this claim, we investigated whether presenting a prospective memory cue during a task that did not require an intention to be performed spontaneously triggered remembering of that intention. In two experiments, participants performed an image-rating task in which a prospective memory task (to press the "Q" key when a target word appeared) was embedded. Then, participants were told that their intention was finished or suspended. Finally, participants performed a lexical decision task in which each target (and a matched control) word appeared. RTs were slower to target words than to control words when the intention was suspended but not when it was finished. These results suggest that target cues associated with suspended intentions can spontaneously trigger remembering but that finished intentions are quickly deactivated.
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Prospective memory in Parkinson disease across laboratory and self-reported everyday performance.
Neuropsychology
PUBLISHED: 05-06-2009
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Prospective memory is a complex cognitive construct ubiquitous in everyday life that is thought to sometimes rely on executive skills commonly affected by Parkinsons disease (PD). The present study investigated the effect of PD on prospective memory tasks with varying demand on executive control processes, namely on the amount of strategic attentional monitoring required for intention retrieval. Individuals with PD but without dementia and healthy adults performed laboratory event-based prospective memory tasks that varied in whether strategic attentional monitoring (nonfocal condition) or spontaneous processes (focal condition) were primarily involved in intention retrieval. Participants also completed a questionnaire rating their frequency of prospective memory failures in everyday life for both self-cued and environment-cued tasks. PD participants performed worse than non-PD participants in the nonfocal, but not focal, condition of the laboratory task. They also reported more everyday failures than non-PD participants for self-cued, but not environment-cued, prospective memory tasks. Thus, nondemented individuals with PD are preferentially impaired on prospective memory tasks for which higher levels of executive control are needed to support intention retrieval. This pattern is consistent across laboratory and reported real-world performance.
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The read-recite-review study strategy: effective and portable.
Psychol Sci
PUBLISHED: 03-20-2009
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Two experiments with college students investigated the effectiveness of the 3R (read-recite-review) strategy for learning from educational texts. The 3R strategy was compared with rereading and note-taking study strategies using free-recall, multiple-choice, and short-answer inference tests immediately after study and after a 1-week delay. In Experiments 1 and 2, 3R improved immediate and delayed free recall of fact-based passages, relative to the rereading and note-taking strategies. In Experiment 2, which used longer, more complex passages on engineering topics, performance on multiple-choice and problem-solving items was better in the 3R than in the rereading condition, and was equivalent in the 3R and note-taking conditions, though 3R took less study time than note taking. An inherent advantage of 3R relative to other testing methods for improving learning is that 3R is under the learners control. These results indicate that it is also an efficacious study technique that capitalizes on the mnemonic potency of retrieval and feedback.
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Incentive effects on event-based prospective memory performance in children and adolescents with traumatic brain injury.
Neuropsychology
PUBLISHED: 03-04-2009
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Prospective memory (PM) is the formation of an intention and remembering to perform this intention at a future time or in response to specific cues. PM tasks are a ubiquitous part of daily life. Currently, there is a paucity of information regarding PM impairments in children with traumatic brain injury (TBI) and less empirical evidence regarding effective remediation strategies to mitigate these impairments. The present study employed two levels of a motivational enhancement (i.e., a monetary incentive) to determine whether event-based PM could be improved in children with severe TBI. In a crossover design, children with orthopedic injuries and mild or severe TBI were compared on two levels of incentive (dollars vs. pennies) given in response to accurate performance. All three groups performed significantly better under the high- versus low-motivation conditions. However, the severe TBI groups high-motivation condition performance remained significantly below the low-motivation condition performance of the orthopedic injury group. PM scores were positively and significantly related to age-at-test, but there were no age-at-injury or time-postinjury effects. Overall, these results suggest that event-based PM can be significantly improved in children with severe TBI.
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The influence of age on memory for distinctive events.
Mem Cognit
PUBLISHED: 02-19-2009
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We examined whether memory for distinctive events is influenced by aging. To do so, we used a semantic isolation paradigm in which people show superior memory for a word when it is presented in a list of items from a different semantic category (e.g., the word table is presented in a list of all bird exemplars) as compared with when the same word (table) is presented in a list of unrelated words. Results showed that both younger and older adults demonstrated an isolation effect in memory, although older adults showed a numerically smaller isolation effect than did younger adults. Results suggest that in contrast with previous findings (Cimbalo & Brink, 1982), older adults can take advantage of this type of distinctiveness to aid memory performance.
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Predicting transfer performance: a comparison of competing function learning models.
J Exp Psychol Learn Mem Cogn
PUBLISHED: 02-13-2009
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The population of linear experts (POLE) model suggests that function learning and transfer are mediated by activation of a set of prestored linear functions that together approximate the given function (Kalish, Lewandowsky, & Kruschke, 2004). In the extrapolation-association (EXAM) model, an exemplar-based architecture associates trained input values with their paired output values. Transfer incorporates a linear rule-based response mechanism (McDaniel & Busemeyer, 2005). Learners were trained on a functional relationship defined by 2 linear-function segments with mirror slopes. In Experiment 1, 1 segment was densely trained and 1 was sparsely trained; in Experiment 2, both segments were trained equally, but the 2 segments were widely separated. Transfer to new input values was tested. For each model, training performance for each individual participant was fit, and transfer predictions were generated. POLE generally better fit the training data than did EXAM, but EXAM was more accurate at predicting (and fitting) transfer behaviors. It was especially telling that in Experiment 2 the transfer pattern was more consistent with EXAMs but not POLEs predictions, even though the presentation of salient linear segments during training dovetailed with POLEs approach.
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The interaction between frontal functioning and encoding processes in reducing false memories.
Neuropsychol Dev Cogn B Aging Neuropsychol Cogn
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ABSTRACT Studies suggest that age differences in false memories may be related to deficits in frontal lobe functioning (FLF; Butler, McDaniel, Dornburg, Price, & Roediger, 2004 , Psychonomic Bulletin & Review, 11, 921). In addition, research has demonstrated that item-specific encoding can reduce false memories in younger adults ( Arndt & Reder, 2003 , Journal of Experimental Psychology: Learning, Memory, and Cognition, 28, 830). In the present study we examined whether younger and older adults who perform poorly on tests designed to assess frontal function would be less likely to benefit from item-specific encoding in a false memory paradigm. In three experiments, participants studied categorized word or picture lists. Encoding manipulations were designed to emphasize either item-specific or relational processing. Younger adults and high FLF older adults showed a reduction in false memories when item-specific processing was implemented. However, low FLF older adults showed a reduction in false memories only when relational processing was impoverished. Results suggest that frontal function directly influences the engagement in distinctive encoding processes.
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Testing and feedback effects on front-end control over later retrieval.
J Exp Psychol Learn Mem Cogn
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In 2 experiments, we explored differences in cognitive control at retrieval on a final test to better understand the mechanisms underlying the powerful boost in recall of previously tested information. Memory retrieval can be enhanced by front-end control processes that regulate the scope of retrieval or by later processes that monitor retrieval to screen out incorrect candidates. In Experiment 1, prior testing with feedback improved front-end control over retrieval compared with restudy, but there was no difference in postretrieval monitoring processes. In Experiment 2, we disentangled the effects of successful retrieval and feedback on later recall by comparing testing with feedback to testing without feedback. Successful retrieval on the initial test improved front-end control processes that restricted access to the target during retrieval, regardless of whether feedback was provided. Compared with restudying, testing did not improve postretrieval monitoring. Results revealed unique contributions of testing and feedback to front-end control processes that optimize memory retrieval.
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Memory Training Interventions: What has been forgotten?
J Appl Res Mem Cogn
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Memory training for older adults often produces gains that are limited to the particular memory tasks encountered during training. We suggest that memory training programs may be misguided by an implicit "generalist" assumption-memory training on a couple of memory tasks will have a positive benefit on memory ability in general. One approach to increase memory-training benefits is to target training for the everyday memory tasks for which older adults struggle. Examples include training retrieval strategies, prospective memory strategies, and strategies for learning and remembering names. Another approach is to design training to foster transfer. Possible elements to improve transfer are increasing the variation that is experienced during the course of training at the level of stimuli and tasks, incorporating "homework" that guides the older adult to become attuned to situations in which the strategies can be applied, and providing older adults with a better understanding of how memory works. Finally, incorporating aerobic exercise into memory training programs may potentiate the acquisition and maintenance of the trained cognitive strategies.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.