Retrospective judgments of confidence in a complex span task.

Although the study of metamemory monitoring originated in predictions for simple span tasks, the study of metacognition for working memory (WM) has been somewhat neglected in comparison with long-term memory. We aimed to fill this gap by exploring the ability to self-assess WM operations. Thirty-four participants performed 16 series of complex span tasks and rated their confidence in a verbal recall paradigm. We manipulated the cognitive load based on the TBRS model in order to analyze the role of attentional resources on both WM and metacognitive evaluations. As expected, we found that recall is affected by cognitive load and we found standard serial position effects. Interestingly, metacognitive evaluations followed the same pattern, and measures of metacognitive sensitivity suggest that participants are able to make item-by-item retrospective judgments reflective of their performance. We discuss how these results contribute to our understanding of metacognitive access to newly-formed WM contents.

Sleep habits and their relation to self-reported attention and class climate in preteens.

OBJECTIVES/DESIGN: Sleep is fundamental in daily functioning, especially in teenagers who are in a critical period of their development. Accordingly, a deteriorated sleep, that is increasingly common in this age group, has been related to poorer school performance. The goal of this cross-sectional study was to collect up-to-date sleep data in preteens, and to examine their relation with two important dimensions for school achievement, which are self-reported attention and class climate at school. METHODS: Data were collected at school in 1151 preteens (597 boys; 554 girls; 11.31 ± 0.62 years old) between June 2021 and March 2022. Self-completion questionnaires evaluated attention and class climate. Sleep questionnaires assessed sleep habits for weekdays and weekends, separately. RESULTS: Preteens reported sleeping 8 h and 39 min during weekdays and 9 h and 32 min during weekends. All sleep measures showed a significant change between weekdays and weekends, leading to a longer and better sleep on weekends, likely to compensate for insufficient sleep during the week. In addition, girls woke-up later and spent more time in bed than boys during weekends. Importantly, during weekdays, correlational analysis showed a relationship between sleep measures and both self-reported attention and class climate scores, suggesting that longer and better sleep was related to better attention and perceived class climate at school. CONCLUSION: This study depicted up-to-date sleep habits in preteens, depending on the day of the week and the gender, and highlighted their relation to two potential contributors of academic success, namely attention and class climate.

Stroke damages attentional maintenance in working memory.

Stroke is the main cause of acquired disability in adults, and specific deficits in working memory (WM) are among the most common cognitive consequences. In neuropsychological routine, WM is most of the time investigated in the framework of the multicomponent model (Baddeley & Hitch, 1974, The psychology of learning and motivation, 47). Using a more recent theoretical WM model, the time-based resource-sharing (TBRS) model (Barrouillet et al., 2011, Psychol. Rev., 118, 175), the aim of the present study was to investigate in young post-stroke patients to which extent attentional maintenance is impaired in WM. To address this question, we discarded other factors known to directly influence WM performance, that is processing speed and short-term memory span. We proposed to 53 post-stroke patients and to 63 healthy controls a complex span paradigm in which participants were asked to alternate between the memorization of a series of images and a concurrent parity judgement task of a series of digits. To investigate the attentional maintenance processes, we manipulated the cognitive load (CL) of the concurrent task. CL effect is typically interpreted as the involvement of attentional maintenance processes. The task was adapted to each participant according to their processing speed and memory span. As expected, the results showed higher recall performance in healthy controls compared with post-stroke patients. Consistent with the literature, we also observed higher performance when the CL was low compared with high. However, the improvement in recall at low CL was smaller for post-stroke patients compared with controls, suggesting that post-stroke WM deficit could be in part due to a deficit of the attentional maintenance processes.

Between-item similarity frees up working memory resources through compression: A domain-general property.

Compression, the ability to recode information in a denser format, is a core property of working memory (WM). Previous studies have shown that the ability to compress information largely benefits WM performance. Importantly, recent evidence also suggests compression as freeing up WM resources, thus enhancing recall performance for other, less compressible information. Contrary to the traditional view positing that between-item similarity decreases WM performance, this study shows that between-item similarity can be used to free up WM resources through compression. Across a series of four experiments, we show that between-item similarity not only enhances recall performance for similar items themselves, but also for other, less compressible items within the same list, and this in the semantic (Experiment 1), phonological (Experiment 2), visuospatial (Experiment 3), and visual (Experiment 4) domains. Across these different domains, a consistent pattern of results emerged: between-item similarity proactively-but not retroactively-enhanced WM performance for other items, and this as compared with a condition in which between-item similarity at the whole-list level was minimized. We propose that between-item similarity in any domain may impact WM using the same underlying machinery: via a compression mechanism, which allows an efficient reallocation of WM resources. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Can activated long-term memory maintain serial order information?

The maintenance of serial order information is a core component of working memory (WM). Many theoretical models assume the existence of specific serial order mechanisms. Those are considered to be independent from the linguistic system supporting maintenance of item information. This is based on studies showing that psycholinguistic factors strongly affect the ability to maintain item information, while leaving order recall relatively unaffected. Recent language-based accounts suggest, however, that the linguistic system could provide mechanisms that are sufficient for serial order maintenance. A strong version of these accounts postulates serial order maintenance as emerging from the pattern of activation occurring in the linguistic system. In the present study, we tested this assumption via a computational modeling approach by implementing a purely activation-based architecture. We tested this architecture against several experiments involving the manipulation of semantic relatedness, a psycholinguistic variable that has been shown to interact with serial order processing in a complex manner. We show that this activation-based architecture struggles to account for interactions between semantic knowledge and serial order processing. This study fails to support activated long-term memory as an exclusive mechanism supporting serial order maintenance.

Distinguishing the Impact of Age on Semantic and Nonsemantic Associations in Episodic Memory.

OBJECTIVES: Refreshing, or the act of briefly foregrounding recently presented but now perceptually absent representations, has been identified as a possible source of age differences in working memory and episodic memory. We investigated whether the refreshing deficit contributes to the well-known age-related deficit for retrieving nonsemantic associations, but has no impact on existing semantic associations. METHOD: Younger and older adults judged the relatedness of stimulus word pairs (e.g., pink-blue or pink-cop) after repeating or refreshing one of the words. During a later source recognition memory test, participants determined whether each item recognized as old was presented on the left or right (nonsemantic source memory) and presented in a related or unrelated pair (semantic source memory). The data were analyzed using a hierarchical Bayesian implementation of a multinomial model of multidimensional source memory. RESULTS: Neither age group exhibited a refreshing benefit to nonsemantic or semantic source memory parameters. There was a large age difference in nonsemantic source memory, but no age difference in semantic source memory. DISCUSSION: The study suggests that the nature of the association is most important to episodic memory performance in older age, irrespective of refreshing, such that source memory is unimpaired for semantically meaningful information.

Do Temporal Regularities during Maintenance Benefit Short-term Memory in the Elderly? Inhibition Capacities Matter.

BACKGROUND/STUDY CONTEXT: Recent research has shown a benefit of temporally regular structure presented during the maintenance period in short-term memory for young adults. Because maintenance is impaired in aging, we investigated whether older adults can also benefit from the temporal regularities for maintenance and how their cognitive capacities might affect this potential benefit. METHODS: Healthy older adults (range: 63-90 years old) had to memorize visually presented letters and maintain them in short-term memory for 6 s until recall. The six-second retention interval was either filled with an isochronous rhythmic sound sequence that provided a temporally regular structure or silent. RESULTS: The effect of the isochronous rhythm on recall performance was modulated by inhibition capacities of older adults: as compared to silence, improved recall performance thanks to the rhythm emerged with increased inhibitory capacity of the participants. CONCLUSION: Even though maintenance of older adults benefits less from the presence of temporal regularities than does the maintenance of younger ones, our findings provide evidence for improved maintenance in short-term memory for older adults in the presence of a temporally regular structure, probably due to enhanced attentional refreshing. It further provides perspectives for training and rehabilitation of age-related working memory deficits.

Aging Influences the Efficiency of Attentional Maintenance in Verbal Working Memory.

OBJECTIVES: Numerous studies reported an age-related deficit in verbal working memory (WM). Beyond the well-established general factors of cognitive aging, the alteration of the specific WM maintenance mechanisms may account for this deficit. This paper aims to investigate the hypothesis that WM attentional maintenance is impaired with age. METHOD: In a WM task adapted to individual short-term memory and processing speed, younger and older participants maintained letters while verbally responding to a concurrent processing task, in order to constrain the use of rehearsal. Critically, the opportunity to use attentional maintenance was manipulated by varying the cognitive load (CL) of the concurrent processing via its nature and pace. RESULTS: Younger participants outperformed older participants and, in both groups, recall performance decreased as the CL increased. Importantly, in line with our predictions, the CL effect was modulated by age. Older adults benefited less from free pauses that allowed participants to engage in attentional maintenance of WM traces. DISCUSSION: Although still effective in normal aging, WM attentional maintenance seems to be altered. It could therefore be a good candidate to account for WM age-related deficits.

Temporal dynamics of maintenance in young and old adults.

The present study investigated the time course of refreshing in young and old adults by analyzing the influence of memory load on response times for the processing of concurrent information. One to five squares sequentially displayed in random locations had to be memorized. Before the serial recall of the squares' locations, participants performed self-paced parity judgments on sequentially presented numbers. Trials without squares-not requiring memorization, but only parity judgments-constituted the control condition. Response times of parity judgments were separated for responses to the first digit and for responses to subsequent digits. In young adults, the results provided evidence for consolidation and refreshing, namely, the linear increase of first and subsequent response times with memory load. For old adults, a different pattern emerged: (1) the mean response time for the first digit processing was longer with memorization than without, probably reflecting task-switching rather than consolidation; and (2) in contrast to young adults, memory load did not affect subsequent response times, suggesting a deficit in the initiation of refreshing. Overall, findings support the hypothesis of impaired refreshing in aging.

What makes working memory traces stable over time?

Understanding the factors that make working memory (WM) traces stable over time is important because WM is the keystone of general cognitive achievement. Two views of attentional WM maintenance have been suggested to account for the long-term retention of WM information. First, the distractors in a WM task are thought to foster the creation of episodic memory cues through covert retrieval. Second, the cognitive load (CL) of the distractors is thought to vary long-term memory instantiation. In this study, we propose an additional parsimonious perspective: the total time during which each trace is under the control of attention in WM is the key to long-term retention. Participants performed a complex span task in which the CL and number of distractors were orthogonally manipulated, and thereafter the participants performed a delayed recall test. Similar to previous findings, the results showed effects of the number of distractors and of CL on delayed recall. Our results went further, however, by showing a non-linear relationship between delayed recall performance and the free time accumulated between encoding and immediate recall. The role of time in episodic memory performance and the underlying WM maintenance mechanism are discussed.

A Computational Model of Working Memory Integrating Time-Based Decay and Interference.

There is still a strong debate in the working memory literature about the cause of forgetting, with many articles providing evidence for the existence of temporal decay and as many publications providing evidence compatible with interference being the only mechanism involved in forgetting. In order to reconcile the two views, this article describes TBRS∗-I (for Time-Based Resource-Sharing∗-Interference), a computational model of working memory which incorporates an interference-based mechanism to the decay-based implementation TBRS∗ within the TBRS theoretical framework. At encoding, memoranda are associated to their context, namely their position in the list. Temporal decay decreases the strength of these associations, but a refreshing process may reactivate it during free time. Distractors may alter the distributed representation of memoranda but refreshing can restore them based on the long-term memory representations. Refreshing is therefore twofold: reactivation plus restoration, each one counteracting the detrimental time-based and interference-based decays, respectively. Two types of interference are implemented: interference by confusion which depends on the degree of overlap between memoranda and distractors and interference by superposition which depends on the similarity between them. TBRS∗-I was tested on six benchmark findings on retention-interval and distractor-processing effects by means of millions of simulations testing the effects of seven factors on memory performance: the number of memoranda, the duration of distractor attentional capture, the duration of free time, the number of distractors, the amount of overlap between memoranda and distractors, the similarity between memoranda and distractors and the homogeneity of distractors (all identical or all distinct). TBRS∗-I replicated classical effects and proved to be a suitable hybrid model integrating both interference and time-based decay. The article also discusses the compatibility of TBRS∗-I with a unitary or dual view of memory and the issue of integrating time and interference in a single model. Computer codes and data are available at https://osf.io/65sna/.

What is attentional refreshing in working memory?

Working memory is one of the most important topics of research in cognitive psychology. The cognitive revolution that introduced the computer metaphor to describe human cognitive functioning called for this system in charge of the temporary storage of incoming or retrieved information to permit its processing. In the past decades, one particular mechanism of maintenance, attentional refreshing, has attracted an increasing amount of interest in the field of working memory. However, this mechanism remains rather mysterious, and its functioning is conceived in very different ways across the literature. This article presents an up-to-date review on attentional refreshing through the joint effort of leading researchers in the domain. It highlights points of agreement and delineates future avenues of research.

Temporal regularities allow saving time for maintenance in working memory.

Recent evidence suggests that working memory (WM) performance can be enhanced in the presence of an isochronous rhythm during the retention interval because it improves refreshing. Considering the cognitive load (CL) effect as an indicator of refreshing, the present study investigated whether an isochronous rhythm might benefit memory performance under varying cognitive load. For that goal, the presence of a regular rhythm and the cognitive load of the concurrent task (i.e., reading of digits that were either same or different within a trial) were systematically varied. Recall performance was decreased by high cognitive load compared with low cognitive load but was improved in the regular rhythm condition compared with the silent condition. No interaction between cognitive load and rhythm was observed. The present results suggest that temporal regularities might speed up the reading of the digits rather than improve the efficiency of refreshing, resulting in more time available for refreshing and, consequently, improved memory performance. These findings are interpreted in the framework of the dynamic attending theory and in the scope of recent models of working memory, which are also considering the temporal components of working memory and the importance of the temporal structure of working memory tasks.

What is the time course of working memory attentional refreshing?

One way of maintaining information in working memory is through attentional refreshing, a process that was recently shown to be independent from verbal rehearsal. In the classical working memory complex span task, the usual assumption is that memoranda are refreshed in a cumulative fashion, starting from the first item, going in a forward order until the latest one, and cycling until there is no time to continue the process. However, there is no evidence that refreshing operates in that way. The present study proposes a computational modelling study, which constitutes a powerful method to investigate alternative hypotheses. Different refreshing schedules are investigated within computational implementation of the time-based resource sharing model. Their ability to fit three sets of behavioral data and to reproduce the major time-based resource sharing predictions were evaluated using standard model selection criteria. Besides an already published schedule in which the attentional focus is expanded, it appeared that one schedule, the least-activated-first, outperforms the classical cumulative one. The memory trace refreshed at a given time is the one that is the least activated in working memory at that time. These findings characterized the time course of attentional refreshing in working memory and specified the contribution of refreshing to primacy and recency effects. Moreover, in the light of various fields of cognitive psychology, we propose that such refreshing schedules can operate without a homunculus within a general framework including cognitive control and strategic considerations.

Under Which Conditions Can Older Participants Maintain Information In Working Memory?

Background/Study Context: Age-related deficits in working memory (WM) are commonly described in the literature. However, age-related deficits in WM maintenance mechanisms have received less attention. Based on recent models of WM, the present study aims at determining the conditions under which older adults are able to maintain information. More precisely, we wondered whether the cognitive load effect, taken as evidence for active maintenance in WM, is observed in normal aging and whether it interacts with the level of interference of a concurrent task. METHODS: Young (mean age = 21.62; SD = 2.51) and healthy older (mean age = 71.92; SD = 5.18) participants performed a complex WM task. They had to remember five images while reading three words presented after each image. We compared trials in which every word was new (inducing high interference) with trials where words were repeated (inducing low interference). The pace at which the reading task was performed was either fast or slow, resulting in a high or a low cognitive load. RESULTS: As suggested in the literature, young participants presented better performance at slow pace compared with fast pace but were not influenced by interference. Older participants also performed better at slow pace but only when interference was low. Interestingly, the older population showed negative correlations between slow-pace trials and switching abilities. Finally, although computational simulations with time-based resource sharing* (TBRS*) provide a good fit for young adult performance, several parameters had to be adjusted to fit the older participants' performance, including duration of trace refreshing. CONCLUSION: Our findings suggest that a decrease in WM performance with aging can be explained by a difficulty in taking advantage of WM maintenance opportunities, especially in conditions of high interference. The computational investigations are consistent with this interpretation given that the parameters to be adjusted involve maintenance in WM. Finally, the computational approach seems a relevant way to address causes of forgetting in aging.

Reconciling Two Computational Models of Working Memory in Aging.

It is well known that working memory performance changes with age. Two recent computational models of working memory, TBRS* and SOB-CS, developed from young adults WM performances are opposed regarding the postulated causes of forgetting, namely time-based decay and interference for TBRS* and SOB-CS, respectively. In the present study, these models are applied on a set of complex span data produced by young and older adults. As expected, these models are unable to account for the older adult data. An investigation on the effect of the main parameters of these models showed that the poorer performance of older adults does not come from a weaker encoding of item but rather from difficulties during the free time that immediately follows each distractor, as well as from a higher level of confusion between items. These results are discussed with respect to the current theories of working memory and aging.

Promoting the experimental dialogue between working memory and chunking: Behavioral data and simulation.

Working memory (WM) is a cognitive system allowing short-term maintenance and processing of information. Maintaining information in WM consists, classically, in rehearsing or refreshing it. Chunking could also be considered as a maintenance mechanism. However, in the literature, it is more often used to explain performance than explicitly investigated within WM paradigms. Hence, the aim of the present paper was (1) to strengthen the experimental dialogue between WM and chunking, by studying the effect of acronyms in a computer-paced complex span task paradigm and (2) to formalize explicitly this dialogue within a computational model. Young adults performed a WM complex span task in which they had to maintain series of 7 letters for further recall while performing a concurrent location judgment task. The series to be remembered were either random strings of letters or strings containing a 3-letter acronym that appeared in position 1, 3, or 5 in the series. Together, the data and simulations provide a better understanding of the maintenance mechanisms taking place in WM and its interplay with long-term memory. Indeed, the behavioral WM performance lends evidence to the functional characteristics of chunking that seems to be, especially in a WM complex span task, an attentional time-based mechanism that certainly enhances WM performance but also competes with other processes at hand in WM. Computational simulations support and delineate such a conception by showing that searching for a chunk in long-term memory involves attentionally demanding subprocesses that essentially take place during the encoding phases of the task.

The impact of cognitive load on delayed recall.

Recent studies have suggested that long-term retention of items studied in a working memory span task depends on the refreshing of memory items-more specifically, on the number of refreshing opportunities. However, it was previously shown that refreshing depends on the cognitive load of the concurrent task introduced in the working memory span task. Thus, cognitive load should determine the long-term retention of items assessed in a delayed-recall test if such retention relies on refreshing. In two experiments, while the amount of refreshing opportunities remained constant, we varied the cognitive load of the concurrent task by either introducing tasks differing in their attentional demands or varying the pace of the concurrent task. To verify that this effect was related to refreshing and not to any maintenance mechanism, we also manipulated the availability of subvocal rehearsal. Replicating previous results, increasing cognitive load reduced immediate recall. This increase also had a detrimental effect on delayed recall. Conversely, the addition of concurrent articulation reduced immediate but not delayed recall. This study shows that both working and episodic memory traces depend on the cognitive load of the concurrent task, whereas the use of rehearsal affects only working memory performance. These findings add further evidence of the dissociation between subvocal rehearsal and attentional refreshing.

Further evidence for temporal decay in working memory: reply to Lewandowsky and Oberauer (2009).

The sources of forgetting in working memory (WM) are a matter of intense debate: Is there a time-related decay of memory traces, or is forgetting uniquely due to representation-based interference? In a previous study, we claimed to have provided evidence supporting the temporal decay hypothesis (S. Portrat, P. Barrouillet, & V. Camos, 2008). However, reanalyzing our data, S. Lewandowsky and K. Oberauer (2009) demonstrated that they do not provide compelling evidence for temporal decay and suggested a class of alternative models favoring a representation-based interference account. In this article, we develop from the most recent proposals made by Lewandowsky and Oberauer 2 of the most plausible extensions of these alternative models. We show that neither of these extensions can account for recent findings related to between-domain WM performance and that both lead to predictions that are contradicted by new empirical evidence. Finally, we show that recent studies that have been claimed to rule out the temporal decay hypothesis do not resist close scrutiny. We conclude that the time-based resource-sharing model remains the most parsimonious way to account for forgetting and restoration of memory traces in WM.

On the law relating processing to storage in working memory.

Working memory is usually defined in cognitive psychology as a system devoted to the simultaneous processing and maintenance of information. However, although many models of working memory have been put forward during the last decades, they often leave underspecified the dynamic interplay between processing and storage. Moreover, the account of their interaction proposed by the most popular A. D. Baddeley and G. Hitch's (1974) multiple-component model is contradicted by facts, leaving unresolved one of the main issues of cognitive functioning. In this article, the author derive from the time-based resource-sharing model of working memory a mathematical function relating the cognitive load involved by concurrent processing to the amount of information that can be simultaneously maintained active in working memory. A meta-analysis from several experiments testing the effects of processing on storage corroborates the parameters of the predicted function, suggesting that it properly reflects the law relating the 2 functions of working memory.