Working Memory Strategy Research Articles

Individual differences in spatial working memory strategies differentially reflected in the engagement of control and default brain networks.

Spatial locations can be encoded and maintained in working memory using different representations and strategies. Fine-grained representations provide detailed stimulus information, but are cognitively demanding and prone to inexactness. The uncertainty in fine-grained representations can be compensated by the use of coarse, but robust categorical representations. In this study, we employed an individual differences approach to identify brain activity correlates of the use of fine-grained and categorical representations in spatial working memory. We combined data from six functional magnetic resonance imaging studies, resulting in a sample of $155$ ($77$ women, $25 \pm 5$ years) healthy participants performing a spatial working memory task. Our results showed that individual differences in the use of spatial representations in working memory were associated with distinct patterns of brain activity. Higher precision of fine-grained representations was related to greater engagement of attentional and control brain systems throughout the task trial, and the stronger deactivation of the default network at the time of stimulus encoding. In contrast, the use of categorical representations was associated with lower default network activity during encoding and higher frontoparietal network activation during maintenance. These results may indicate a greater need for attentional resources and protection against interference for fine-grained compared with categorical representations.

Individual differences in spatial working memory strategies differentially reflected in the engagement of control and default brain networks.

Spatial locations can be encoded and maintained in working memory using different representations and strategies. Fine-grained representations provide detailed stimulus information, but are cognitively demanding and prone to inexactness. The uncertainty in fine-grained representations can be compensated by the use of coarse, but robust categorical representations. In this study, we employed an individual differences approach to identify brain activity correlates of the use of fine-grained and categorical representations in spatial working memory. We combined data from six fMRI studies, resulting in a sample of 155 (77 women, 25 ± 5 years) healthy participants performing a spatial working memory task. Our results showed that individual differences in the use of spatial representations in working memory were associated with distinct patterns of brain activity. Higher precision of fine-grained representations was related to greater engagement of attentional and control brain systems throughout the task trial, and the stronger deactivation of the default network at the time of stimulus encoding. In contrast, the use of categorical representations was associated with lower default network activity during encoding and higher frontoparietal network activation during maintenance. These results may indicate a greater need for attentional resources and protection against interference for fine-grained compared to categorical representations.

Impact of on-call shifts on working memory and the role of burnout, sleep, and mental well-being in trainee physicians

ABSTRACT Background Optimal cognitive functions, including working memory (WM), are crucial to enable trainee physicians to perform and excel in their clinical practice. Several risk factors, including on-call shifts, poor mental health, burnout, and sleep problems, can impair clinical practice in trainee physicians, potentially through cognitive impairment; however, these associations have not been fully explored. Objective This study investigated the effect of on-call shifts on WM among trainee physicians and its association with burnout, depression, anxiety, affect, and sleep. Materials and methods This cross-sectional study involved 83 trainee physicians (45% male). We measured demographic and training-related factors including on-call shifts and working hours. We also assessed depressive symptoms (PHQ-9), both state and trait anxiety (STAI total score), burnout (OLBI total score), positive and negative affect scores (PANAS), and sleep disturbances (PSQI total score). WM was evaluated using spatial working memory (SWM) strategy scores that reflected performance and total error counts. Results Trainee physicians with more on-calls per month had significantly worse depressive symptoms, burnout scores, and sleep, as well as more negative affect. While controlling for covariates, being on-call more times per month was significantly associated with worse WM. Worse depressive symptoms and burnout scores were also significantly associated with impaired WM. Conclusion Working more on-call shifts is associated with compromised WM. Trainee physicians who experienced more depressive symptoms and burnout had worse WM.

Decoding the content of working memory in school-aged children

Developmental improvements in working memory (WM) maintenance predict many real-world outcomes, including educational attainment. It is thus critical to understand which WM mechanisms support these behavioral improvements, and how WM maintenance strategies might change through development. One challenge is that specific WM neural mechanisms cannot easily be measured behaviorally, especially in a child population. However, new multivariate decoding techniques have been designed, primarily in adult populations, that can sensitively decode the contents of WM. The goal of this study was to deploy multivariate decoding techniques known to decode memory representations in adults to decode the contents of WM in children. We created a simple computerized WM game for children, in which children maintained different categories of information (visual, spatial or verbal). We collected electroencephalography (EEG) data from 20 children (7–12-year-olds) while they played the game. Using Multivariate Pattern Analysis (MVPA) on children's EEG signals, we reliably decoded the category of the maintained information during the sensory and maintenance period. Across exploratory reliability and validity analyses, we examined the robustness of these results when trained on less data, and how these patterns generalized within individuals throughout the testing session. Furthermore, these results matched theory-based predictions of WM across individuals and across ages. Our proof-of-concept study proposes a direct and age-appropriate potential alternative to exclusively behavioral WM maintenance measures in children. Our study demonstrates the utility of MVPA to measure and track the uninstructed representational content of children's WM. Future research could use our technique to investigate children's WM maintenance and strategies.

Abstract 14714: Long-Term Neurocognitive Safety of LDL-C Lowering With Evolocumab: Open-Label Extension Data From FOURIER

Background: Concerns have been raised about low LDL-C levels and possible adverse effects on cognition. PCSK9 inhibitors markedly lower LDL-C, yet EBBINGHAUS, a prespecified substudy within the FOURIER trial, did not show adverse cognitive changes with evolocumab over 19 months median follow-up. Purpose: To investigate the long-term effects of evolocumab on cognitive function. Methods: EBBINGHAUS was a substudy of cognitive function using the Cambridge Neuropsychological Test Automated Battery (CANTAB) within the FOURIER randomized trial of evolocumab vs placebo in patients with established ASCVD. Patients in North America and Europe who completed EBBINGHAUS on study drug were eligible for an open-label extension (OLE) study with evolocumab. The primary endpoint was change in spatial working memory strategy index of executive function score (SWMI) from baseline over time. Secondary endpoints were measures of working memory, episodic memory, and psychomotor speed. A paired t-test was used to compare baseline vs post-baseline scores during OLE. Results: Of 1204 patients from EBBINGHAUS, 306 entered the OLE and were treated with evolocumab for a median of 5.1 years. Median achieved LDL-C was 34 mg/dL (IQR 21-50). No significant change in SWMI occurred during the OLE period overall [mean (±SD) change -0.1±2.7, p=0.73] or when stratified by original randomized allocation ( Figure 1A ). For secondary outcomes, one showed no change during the OLE period, two showed small changes (10-15% of SD), but these were directionally inconsistent (one higher, one lower). In 152 patients originally randomized to evolocumab, there was no significant change in SWMI from randomization through long-term follow-up over a median of 6.7 and a maximum of 7.2 years (mean change 0.1±2.6, p=0.66) ( Figure 1B ). Conclusion: Evolocumab did not lead to any apparent long-term decline in cognitive function through follow-up extending up to 7.2 years.

Evidence of a positive effect of verbal cumulative rehearsal on serial order working memory, as early as 4 years old.

The use of a verbal rehearsal strategy (repeating the items to be remembered to oneself in serial order) has been identified as a key factor in explaining working memory (WM) development. However, the debate remains open with regard to the age at which children are able to use it, and the actual benefits of using such a strategy. Numerous methodological constraints to identify WM strategies limit the interpretation of current findings reported in the literature. Moreover, the sequential nature of the cumulative rehearsal strategy means that its use may have a particular influence on maintaining serial order information. The present study aimed to examine (a) whether children aged 4, 5, and 6 (n = 74, 39 female, n = 61, 29 female, and n = 72, 29 female, respectively) were able to implement an instructed verbal rehearsal strategy and (b) the benefits of using such a strategy in terms of WM performance. Specifically, we invited children to use cumulative rehearsal, naming (simple rehearsal), or no strategy when performing verbal WM tasks (immediate serial recall and item and order serial recognition). Moreover, the specific influence of instructed strategies on item and serial order maintenance was assessed in the different age groups. While the benefits of using the naming strategy were limited, cumulative rehearsal instruction increased WM performance in all age groups, particularly for serial order information. Our results demonstrate that, as early as 4 years old, children were able to implement, and benefit from a short period of cumulative rehearsal instruction. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

EFFECTS OF EFL VOCABULARY INSTRUCTION ON ARAB LEARNERS’ USAGE OF LEXICAL COLLOCATIONS IN SPEAKING PERFORMANCE

For many decades, the role of the learner's mother tongue in foreign and second language classrooms has been a topic of debate. EFL teachers may present and explain vocabulary in student’s native language, they may do so in the target language, or they may keep switching between the two. The aim of the current study is to investigate how EFL vocabulary instruction affects EFL Arab learners' usage of English lexical collocations in their speaking performance through implementing several working memory strategies. A quasi-experimental, mixed method design was adopted comparing teacher code-switching and L2 explanations in teaching lexical collocations. Within twenty-six sessions of teaching intervention to teach lexical collocations to EFL learners, the study measured learners' responses to vocabulary instruction in the two experimental groups. The study also explored how working memory strategies used by learners in response to vocabulary instruction may enhance learning lexical collocations by EFL learners. For this purpose, 45 Arab elementary EFL learners in the English language centre in Kuala Lumpur were divided into three groups (code-switching, L2 explanation group, and control group); they completed three speaking tests, pre, and post-test and delayed post-test. The results indicated that both the code-switching group and the L2 explanation group were improving their vocabulary; however, the study showed an important role of L1 in learning lexical collocation. The findings revealed that working memory strategies assisted learners to retain collocations effectively. The study included several pedagogical suggestions and implications for future research to improve the standard for teaching, learning, and retention of lexical collocations in speaking performance.

How do intentions modulate the effect of working memory on long-term memory?

Previous studies found that working memory maintenance contributes to long-term memory formation, and some evidence suggests that this effect could be larger when individuals are informed of the final long-term memory test. However, no study so far has explored whether and how working memory maintenance adapts when long-term retention is intentional. In this study, we conducted two experiments using verbal complex span tasks followed by delayed-recall tests. In both experiments, we evaluated working memory maintenance by varying the cognitive load of the concurrent task and with memory strategies reports. We manipulated intentions to remember at long term by warning participants of the final delayed recall or not (Experiment 1) or by monetarily rewarding immediate or delayed-recall performance (Experiment 2). We found no evidence that intentions changed the working memory maintenance mechanisms and strategies used, yet the cognitive load (Experiment 1) and rewards (Experiment 2) effects on delayed recalls were increased with a higher intention to remember at long term. We discuss possible interpretations for these results and suggest that the effect of intentions may not be due to a change in the kind of maintenance mechanisms used. As our results cannot be explained solely by encoding or maintenance processes, we instead propose that intentions produce a combined change in encoding and maintenance. However, the exact nature of this modulation will need further investigation. We conclude that understanding how intentions modulate the effect of working memory on long-term memory could shed new light on their relationship.

Differential working memory function between phonological and visuospatial strategies: a magnetoencephalography study using a same visual task.

Previous studies have reported that, in working memory, the processing of visuospatial information and phonological information have different neural bases. However, in these studies, memory items were presented via different modalities. Therefore, the modality in which the memory items were presented and the strategy for memorizing them were not rigorously distinguished. In the present study, we explored the neural basis of two working memory strategies. Nineteen right-handed young adults memorized seven sequential directions presented visually in a task in which the memory strategy was either visuospatial or phonological (visuospatial/phonological condition). Source amplitudes of theta-band (5-7 Hz) rhythm were estimated from magnetoencephalography during the maintenance period and further analyzed using cluster-based permutation tests. Behavioral results revealed that the accuracy rates showed no significant differences between conditions, while the reaction time in the phonological condition was significantly longer than that in the visuospatial condition. Theta activity in the phonological condition was significantly greater than that in the visuospatial condition, and the cluster in spatio-temporal matrix with p < 5% difference extended to right prefrontal regions in the early maintenance period and right occipito-parietal regions in the late maintenance period. The theta activity results did not indicate strategy-specific neural bases but did reveal the dynamics of executive function required for phonological processing. The functions seemed to move from attention control and inhibition control in the prefrontal region to inhibition of irrelevant information in the occipito-parietal region.

Cognitive stimulation of executive functions through computational thinking

The healthy development of cognitive functions, including executive functions, has been shown to depend mainly on the experiences and learning opportunities of people, especially during childhood. Over the past few years, researchers have been studying the impacts of diverse types of interventions on children’s cognitive development in which computational thinking programs are a recent field. This pilot study evaluated the effect of computational thinking training based on the “Programming for Children” program on the executive functions of children aged 10 and 11 years: working memory, inhibition, and planning (N = 30). The results showed that children in the experimental group improved on tests of visuospatial working memory, cognitive inhibition, and sequential planning compared with the control group. However, tests of verbal working memory, memory strategy, and visual spatial planning did not show any observed changes. Although this was an exploratory study, and its findings should be interpreted cautiously due to the small sample size, the findings support the relevance and feasibility of conducting similar larger studies with larger samples.

Stress specifically deteriorates working memory in peripheral neuropathic pain and fibromyalgia.

This study aimed to explore the influence of chronic stress, measured through hair cortisol, on executive functions in individuals with chronic pain. We expected that there would be significant differences in chronic stress and executive functioning between pain patients and healthy controls, as well as between primary and secondary pain classifications. We also hypothesized that hair cortisol concentration was predictive of worse performance on tests of executive functions, controlling for objective and subjective covariates. For this study, 122 participants provided a hair sample (n = 40 with fibromyalgia; n = 24 with peripheral neuropathic pain; n = 58 matched healthy controls). Eighty-four of these participants also completed highly detailed testing of executive functions (n = 40 with fibromyalgia; n = 24 with peripheral neuropathic pain; n = 20 healthy controls). To assess differences in stress levels and executive functions, t-tests were used to compare patients with controls as well as fibromyalgia with peripheral neuropathic pain. Then, univariate regressions were used to explore associations between stress and executive functioning in both chronic pain classifications. Any significant univariate associations were carried over to hierarchical multivariate regression models. We found that patients with chronic pain had significantly higher cortisol levels than healthy controls, but all groups showed similar executive functioning. Hierarchical multiple regression analyses disclosed that in a model controlling for age, sex and pain medication usage, hair cortisol levels explained 8% of the variance in spatial working memory strategy in individuals with chronic pain. The overall model explained 24% of the variance in spatial working memory. In a second model using imputed data, including both objective and subjectively reported covariates, hair cortisol levels explained 9% of the variance, and the full model 31% of the variance in spatial working memory performance. Higher levels of cortisol indicated worse performance. In this study, an applied measure of chronic stress, namely hair cortisol, explained a substantial part of the variance on a spatial working memory task. The current results have important implications for understanding and treating cognitive impairments in chronic pain.

Exploring the neurobiology of Merge at a basic level: insights from a novel artificial grammar paradigm.

Human language allows us to generate an infinite number of linguistic expressions. It's proposed that this competence is based on a binary syntactic operation, Merge, combining two elements to form a new constituent. An increasing number of recent studies have shifted from complex syntactic structures to two-word constructions to investigate the neural representation of this operation at the most basic level. This fMRI study aimed to develop a highly flexible artificial grammar paradigm for testing the neurobiology of human syntax at a basic level. During scanning, participants had to apply abstract syntactic rules to assess whether a given two-word artificial phrase could be further merged with a third word. To control for lower-level template-matching and working memory strategies, an additional non-mergeable word-list task was set up. Behavioral data indicated that participants complied with the experiment. Whole brain and region of interest (ROI) analyses were performed under the contrast of "structure > word-list." Whole brain analysis confirmed significant involvement of the posterior inferior frontal gyrus [pIFG, corresponding to Brodmann area (BA) 44]. Furthermore, both the signal intensity in Broca's area and the behavioral performance showed significant correlations with natural language performance in the same participants. ROI analysis within the language atlas and anatomically defined Broca's area revealed that only the pIFG was reliably activated. Taken together, these results support the notion that Broca's area, particularly BA 44, works as a combinatorial engine where words are merged together according to syntactic information. Furthermore, this study suggests that the present artificial grammar may serve as promising material for investigating the neurobiological basis of syntax, fostering future cross-species studies.

Strategy and Core Cognitive Training Effects on Working Memory Performance: A Systematic Review and Meta-Analysis

ABSTRACT The field of cognitive training (CT) has been researched for over a century. However, there is still a debate regarding its ability to produce cognitive improvement, especially in working memory (WM) indices. This meta-analysis examined whether there is an advantage in training gains by comparing the results of two specific WM training approaches, Core Training (CRT) and Strategy Training (ST). Meta-analytic techniques were used to summarize 28 independent effect sizes from 24 studies with 1521 subjects, calculated only from studies that compared both training approaches in a single study. We found moderate effect sizes of trained tasks improvement with a clear advantage to ST over CRT, from which younger trainees benefitted the most. However, this advantage has almost disappeared for untrained tasks due to the limited improvement each approach produced on its own.

Working Memory and Processing Speed Predict Math Skills in Pediatric Brain Tumor Survivors.

Childhood brain tumor (BT) survivors are at risk for working memory (WM) and processing speed (PS) deficits, which impact other cognitive domains. This study aimed to characterize WM, PS, and untimed mathematics calculation performance in pediatric BT survivors at least 2 years post-diagnosis, identify medical factors associated with deficits in mathematics, and examine whether WM and/or PS predict mathematics performance in this clinical sample. Retrospective data were gathered from 72 BT survivors between 7 and 21 years of age ( M =13.64y, SD =4.01y) for a clinical neuropsychologic evaluation. All participants completed Wechsler measures of WM and PS and a measure of untimed mathematics calculation. WM, PS, and the mathematics calculation were significantly lower than the normative mean. Math scores were not correlated with any of the examined medical factors. PS was negatively correlated with the Neurological Predictor Scale and positively correlated with age at diagnosis. Both WM and PS were associated with math outcomes and accounted for 30.4% and 19.2% of the variance, respectively. The findings indicate that WM and PS contribute to mathematics performance in pediatric BT survivors. Examining mathematics performance should be a part of clinical neuropsychological evaluations. Interventions to improve mathematics performance in this population should also focus on WM and compensatory strategies for slowed PS.

Age and sex impact on visuospatial working memory (VSWM), mental rotation, and cognitive strategies during navigation

This study assessed the impact of sex and typical aging on visuospatial working memory (VSWM), mental rotations, and navigational strategies using behavioral information. Fifty healthy participants regrouped in older (OA) and young adults (YA) performed the Walking Corsi test (WalCT) and the Redrawn Mental Rotation Test (MRT) to explore mental rotation abilities. We recorded kinematic data such as locomotion trajectories, and spatial orientations during navigation. We created a new method of data analysis for the WalCT performances and compared it with the classical approach. This original method allowed us to identify cognitive strategies based on errors analysis. Our data suggested that VSWM and mental rotation capacities in locomotion were modulated by age (YA scored higher than OA), and sex (Young Adult Males (YA-M) having higher performance than Young Adult Females (YA-F). We observed a preferential use of cognitive strategies related to sex; YA-F relied more on egocentric strategies whereas YA-M relied more on allocentric strategies. The preferential use of cognitive strategies in the YA group was not observed in the OA group producing more random errors per sequence. The results suggest the effects that age and sex have on VSWM, cognitive strategies, and mental rotation during navigation and highlight the importance of navigational strategies training.

A Haptic Nonverbal Cognitive Test for Children and Adolescents With Visual Impairment

Introduction: The objective of the current study was to design and pilot-test a nonverbal intelligence test for children and adolescents with visual impairment (i.e., blindness and low vision) aged 10 to 16 years. Method: A three-dimensional haptic matrix test of nonverbal cognitive abilities (3-DHMT-CA), initially developed for adults with visual impairment, was adapted and administered to 25 juveniles with severe low vision or blindness and 25 sighted peers. The test consisted of 22 tactual matrices with a missing element, and juveniles were asked to understand the logical scheme underlying each matrix and to complete it. Convergent validity was assessed in the sighted group with the Standard Progressive Matrices. Divergent validity was measured with the Verbal Comprehension Index (VCI) and the Working Memory Index (WMI) of the Italian version of the Wechsler Intelligence Scale for Children–Fourth Edition. Between-group differences were analyzed with Student’s t-test and ANOVA. Results: Results show a high correlation with the convergent measure (with the Standard Progressive Matrices), and the moderate correlations with divergent measures (VCI and WMI). Between-group differences showed significantly higher scores for sighted peers than juveniles with visual impairment at 3-DHMT-CA, and non-significant differences at VCI and WMI. Discussion: This haptic nonverbal cognitive test showed good psychometric properties, but it needs to be validated in a larger sample with a qualitative analysis of solution strategies because juveniles with visual impairment seem to use different verbal and working memory strategies. Implications for Practitioners: The 3-DHMT-CA and the haptic two-hands modality seem to be suitable to test nonverbal cognitive abilities in juveniles with visual impairment. Practitioners should focus on empowering verbal and working memory abilities, since they may affect nonverbal cognitive abilities as well.

Neural Evidence for Different Types of Position Coding Strategies in Spatial Working Memory.

Sustained neural activity during the delay phase of spatial working memory tasks is compelling evidence for the neural correlate of active storage and maintenance of spatial information, however, it does not provide insight into specific mechanisms of spatial coding. This activity may reflect a range of processes, such as maintenance of a stimulus position or a prepared motor response plan. The aim of our study was to examine neural evidence for the use of different coding strategies, depending on the characteristics and demands of a spatial working memory task. Thirty-one (20 women, 23 ± 5 years) and 44 (23 women, 21 ± 2 years) participants performed a spatial working memory task while we measured their brain activity using fMRI in two separate experiments. Participants were asked to remember the position of a briefly presented target stimulus and, after a delay period, to use a joystick to indicate either the position of the remembered target or an indicated non-matching location. The task was designed so that the predictability of the response could be manipulated independently of task difficulty and memory retrieval process. We were particularly interested in contrasting conditions in which participants (i) could use prospective coding of the motor response or (ii) had to rely on retrospective sensory information. Prospective motor coding was associated with activity in somatomotor, premotor, and motor cortices and increased integration of brain activity with and within the somatomotor network. In contrast, retrospective sensory coding was associated with increased activity in parietal regions and increased functional connectivity with and within secondary visual and dorsal attentional networks. The observed differences in activation levels, dynamics of differences over trial duration, and integration of information within and between brain networks provide compelling evidence for the use of complementary spatial working memory strategies optimized to meet task demands.

Modeling mean estimation tasks in within-trial and across-trial contexts.

The mean estimation task, which explicitly asks observers to estimate the mean feature value of multiple stimuli, is a fundamental paradigm in research areas such as ensemble coding and cue integration. The current study uses computational models to formalize how observers summarize information in mean estimation tasks. We compare model predictions from our Fidelity-based Integration Model (FIM) and other models on their ability to simulate observed patterns in within-trial weight distribution, across-trial information integration, and set-size effects on mean estimation accuracy. Experiments show non-equal weighting within trials in both sequential and simultaneous mean estimation tasks. Observers implicitly overestimated trial means below the global mean and underestimated trial means above the global mean. Mean estimation performance declined and stabilized with increasing set sizes. FIM successfully simulated all observed patterns, while other models failed. FIM's information sampling structure provides a new way to interpret the capacity limit in visual working memory and sub-sampling strategies. As a model framework, FIM offers task-dependent modeling for various ensemble coding paradigms, facilitating research synthesis across different studies in the literature.

Effects of Ketamine and Midazolam on Simultaneous EEG/fMRI Data During Working Memory Processes

Reliable measures of cognitive brain activity from functional neuroimaging techniques may provide early indications of efficacy in clinical trials. Functional magnetic resonance imaging and electroencephalography provide complementary spatiotemporal information and simultaneous recording of these two modalities can remove inter-session drug response and environment variability. We sought to assess the effects of ketamine and midazolam on simultaneous electrophysiological and hemodynamic recordings during working memory (WM) processes. Thirty participants were included in a placebo-controlled, three-way crossover design with ketamine and midazolam. Compared to placebo, ketamine administration attenuated theta power increases and alpha power decreases and midazolam attenuated low beta band decreases to increasing WM load. Additionally, ketamine caused larger blood-oxygen-dependent (BOLD) signal increases in the supplementary motor area and angular gyrus, and weaker deactivations of the default mode network (DMN), whereas no difference was found between midazolam and placebo. Ketamine administration caused positive temporal correlations between frontal-midline theta (fm-theta) power and the BOLD signal to disappear and attenuated negative correlations. However, the relationship between fm-theta and the BOLD signal from DMN areas was maintained in some participants during ketamine administration, as increasing theta strength was associated with stronger BOLD signal reductions in these areas. The presence of, and ability to manipulate, both positive and negative associations between the BOLD signal and fm-theta suggest the presence of multiple fm-theta components involved in WM processes, with ketamine administration disrupting one or more of these theta-linked WM strategies.

Developing EFL Vocabulary Learning Among Faculty of Education Students thorough Using Working Memory Strategy

Developing EFL Vocabulary Learning Among Faculty of Education Students thorough Using Working Memory Strategy