Low Working Memory Capacity Research Articles

Comparison of Resting-State Brain Activation between Healthy Normal and Low Auditory-Verbal Working Memory Capacity Participants

Working memory (WM) capacity is the ability to maintain attention and store information briefly in the mind. However, each individual has a limited WM capacity that varies from one person to another. An individual can be categorized as having either normal or low WM capacity. This study aimed to evaluate and compare brain activations of healthy individuals with low and normal auditory-verbal WM capacity. A total of 39 healthy male young adults were recruited from local universities for this study. They were categorized into the normal and low auditory-verbal WM capacity group based on their score in the Malay Version of Auditory Verbal Learning Test (MVAVLT). All participants underwent resting-state functional magnetic resonance imaging (rs-fMRI) scans. The functional data were analyzed using Statistical Parametric Mapping (SPM) and Wake Forest University (WFU) Pickatlas softwares. Brain activations and resting-state amplitude fluctuation (rsAF) were contrasted between groups to determine whether there were any significant differences caused by the different auditory-verbal WM capacity. The findings indicated that the low auditory-verbal WM capacity group showed significantly higher cortical activations in the left lingual gyrus, bilateral middle temporal gyrus, left calcarine, left superior frontal gyrus, and left precuneus as compared to normal auditory-verbal WM capacity group. It is suggested that the higher activation of these brain areas in low verbal-auditory WM capacity participants was attributed to the lower neural adaptability of the brain at rest.

Listening Effort in Cochlear Implant Users: The Effect of Speech Intelligibility, Noise Reduction Processing, and Working Memory Capacity on the Pupil Dilation Response.

This study aimed to evaluate the effect of speech recognition performance, working memory capacity (WMC), and a noise reduction algorithm (NRA) on listening effort as measured with pupillometry in cochlear implant (CI) users while listening to speech in noise. Speech recognition and pupil responses (peak dilation, peak latency, and release of dilation) were measured during a speech recognition task at three speech-to-noise ratios (SNRs) with an NRA in both on and off conditions. WMC was measured with a reading span task. Twenty experienced CI users participated in this study. With increasing SNR and speech recognition performance, (a) the peak pupil dilation decreased by only a small amount, (b) the peak latency decreased, and (c) the release of dilation after the sentences increased. The NRA had no effect on speech recognition in noise or on the peak or latency values of the pupil response but caused less release of dilation after the end of the sentences. A lower reading span score was associated with higher peak pupil dilation but was not associated with peak latency, release of dilation, or speech recognition in noise. In CI users, speech perception is effortful, even at higher speech recognition scores and high SNRs, indicating that CI users are in a chronic state of increased effort in communication situations. The application of a clinically used NRA did not improve speech perception, nor did it reduce listening effort. Participants with a relatively low WMC exerted relatively more listening effort but did not have better speech reception thresholds in noise.

The Association Between Sleep Quality and Working Memory of Medical Faculty Malikussaleh University Students

Background: Working memory is a form of storage of information that is relevant to the activity being worked out in a short time and a limited amount of information. The working memory capacity is influenced by sleep quality. Increased human activity in the modern era, causing less attention to the quality and quantity of sleep. Recent study showed that the prevalence of medical student who have poor sleep quality is quite high, reaching 76%. Poor quality of sleep will cause a person to think and work more slowly, make mistakes, and have a hard time remembering things. Objective: This research aims to know the relationship of sleep quality with working memory capacity in medical students of Malikussaleh University. Methods: This research was an analytical study with cross- sectional approach, and the Fisher test was used as the statistical test. Proportional stratified random sampling was used to obtained 71 samples of students who had qualified inclusion and exclusion criterias. Results: The results showed that 84,5% of students had poor quality of sleep and 56,3% of students had low working memory capacity. Statistical analysis by Fisher test showed the value of p < 0,05. Conclusion: there is an association between sleep quality and the capacity of working memory in the Faculty of Medicine students of Malikussaleh University.

Individual Differences in Working Memory Capacity Modulate Electrophysiological Correlates of Semantic Negative Priming From Single Words.

In the present study, event-related potentials (ERPs) were registered during a semantic negative priming (NP) task in participants with higher and lower working memory capacity (WMC). On each trial participants had to actively ignore a briefly presented single prime word, which was followed either immediately or after a delay by a mask. Thereafter, either a semantically related or an unrelated target word was presented, to which participants made a semantic categorization judgment. The ignored prime produced a behavioral semantic NP in delayed (but not in immediate) masking trials, and only for participants with a higher-WMC. Both masking type and WMC also modulated ERP priming effects. When the ignored prime was immediately followed by a mask (which impeded its conscious identification) a reliable N400 modulation was found irrespective of participants’ WMC. However, when the mask onset following the prime was delayed (thus allowing its conscious identification), an attenuation of a late positive ERP (LPC) was observed in related compared to unrelated trials, but only in the higher-WMC group showing reliable behavioral NP. The present findings demonstrate for the first time that individual differences in WMC modulate both behavioral measures and electrophysiological correlates of semantic NP.

Working memory differences in prosodic imitation

Speakers strongly vary in their imitation abilities, but the factors underlying this variation are still unclear. This study examined whether individual differences in working memory affect the accuracy of imitation of phonological and phonetic aspects of French prosody. Thirty-six French native speakers were asked to listen to twenty sentences extracted from a read and a spontaneous speech corpus, and to repeat the words and the way the utterances were said. Overall, obligatory phonological events (boundary tones and the H* tone of LH* rises) were more accurately reproduced than optional phonological ones (the Hi tone of LHi rises) and their speaker-specific phonetic details. Speakers with higher working memory capacities were more accurate in phonological imitation of both obligatory and optional phonological events, possibly because of their increased capacity in retaining the prosodic characteristics of the utterances. Imitating read speech, which was richer in terms of number of LHi rises, was slightly more difficult for speakers with low working memory capacities. There was no relation between working memory and imitation of phonetic aspects, which showed more idiosyncratic patterns of imitation. Our findings indicate that working memory constraints should be taken into account in modelling prosodic imitation, along with linguistic and task-specific factors.

Modulation of Visual Working Memory Performance via Different Theta Frequency Stimulations.

Previous studies have found that transcranial alternating current stimulation (tACS) can significantly enhance individuals’ working memory performance. However, it is still unclear whether the memory performance enhancement was attributed to the quantity or the quality of working memory. The current study applies tACS over the right parietal cortex at slower (4 Hz) and faster (7 Hz) frequencies to participants with high and low working memory capacities in a color recall memory task. This enabled us to explore the tACS effects on the quantity and quality of the working memory for individuals with different memory capacities. The results revealed that slower frequency (4 Hz) tACS enhanced the quality of memory representations, and faster frequency (7 Hz) tACS principally impaired the quantity of working memory. The underlying mechanism of this effect might be that tACS at different frequencies modulate the memory resources, which then selectively affect the quantity and quality of memory representations. Importantly, individual traits, as well as memory strategies, may be crucial factors to consider when testing the effect of tACS on working memory performance.

Capacity differences in working memory based on resting state brain networks

Herein, we compared the connectivity of resting-state networks between participants with high and low working memory capacity groups. Brain network connectivity was assessed under both resting and working memory task conditions. Task scans comprised dual-task (reading sentences while memorizing target words) and single-task (reading sentences) conditions. The low capacity group showed relatively stronger connectivity during resting-state in most brain regions, and the high capacity group showed a stronger connectivity between the medial prefrontal and posterior parietal cortices. During task performance, the dorsal attention and salience networks were relatively strongly connected in the high capacity group. In the comparison between dual- and single-task conditions, increased coupling between the anterior cingulate cortex and other attentional control-related areas were noted in the high capacity group. These findings suggest that working memory differences are related with network connectivity variations in attentional control-associated regions during both resting and task performance conditions.

Spatial Separation and Working Memory Capacity Affect Selective Visual Attention in the Periphery.

The current study aimed to examine the effects of spatial separation and working memory capacity on selective visual attention. We investigated differences in the ability to identify the two covertly attended stimuli that appeared either along one of the meridians (e.g., both along the horizontal) or along two of the meridians (e.g., one along the horizontal and one along the vertical) in the attention-window task. Two visual stimuli in the periphery could be perceived along wider extents of the attentional focus’ meridians (horizontal, vertical, and diagonal) when they were located along the same meridian (e.g., horizontal) compared to two different ones (e.g., horizontal and vertical). Subjects with high working memory capacity outperformed subjects with lower working memory capacity in both conditions and stimuli presented on two meridians were less accurately perceived. The findings support the proposal that individual differences in working memory capacity are important for selective spatial visual attention.

The development of metacognitive accuracy in working memory across childhood.

Growth in working memory capacity, the number of items kept active in mind, is thought to be an important aspect of childhood cognitive development. Here, we focused on participants' awareness of the contents of their working memory, or meta-working memory, which seems important because people can put cognitive abilities to best use only if they are aware of their limitations. In two experiments on the development of meta-working memory in children between 6 and 13 years old and adults, participants were to remember arrays of colored squares and to indicate if a probe item was in the array. On many trials, before the probe recognition test, they reported a metajudgment, how many items they thought they remembered. We compared meta-working memory judgments to actual performance and looked for associations between these measures on individual and trial-by-trial levels. Despite much lower working memory capacity in younger children there was little change in meta-working memory judgments across age groups. Consequently, younger participants were much less realistic in their metajudgments concerning their working memory capability. Higher cognitive capacity was associated with more accurate meta-working memory judgments within an age group. Trial-by-trial tuning of metajudgments was evident only in young adults and then only for small array set sizes. In sum, meta-working memory ability is a sophisticated skill that develops with age and may be an integral aspect of the development of working memory across the school years. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Making the rich richer: Frontoparietal tDCS enhances transfer effects of a single-session distractor inhibition training on working memory in high capacity individuals but reduces them in low capacity individuals

Working memory (WM) performance depends on the ability to extract relevant while inhibiting irrelevant information from entering the WM storage. This distractor inhibition ability can be trained and is known to induce transfer effects on WM performance. Here we asked whether transfer on WM can be boosted by transcranial direct current stimulation (tDCS) during a single-session distractor inhibition training. As WM performance is ascribed to the frontoparietal network, in which prefrontal areas are associated with inhibiting distractors and posterior parietal areas with storing information, we placed the anode over the prefrontal and the cathode over the posterior parietal cortex during a single-session distractor inhibition training. This network-oriented stimulation protocol should enhance inhibition processes by shifting the neural activity from posterior to prefrontal regions. WM improved after a single-session distractor inhibition training under verum stimulation but only in subjects with a high WM capacity. In subjects with a low WM capacity, verum tDCS reduced the transfer effects on WM. We assume tDCS to strengthen the frontostriatal pathway in individuals with a high WM capacity leading to efficient inhibition of distractors. In contrast, the cathodal stimulation of the posterior parietal cortex might have hindered usual compensational mechanism in low capacity subjects, i.e. maintaining also irrelevant information in memory. Our results thus stress the need to adjust tDCS protocols to well-founded knowledge about neural networks and individual cognitive differences.

Age-related Differences in the Effects of Working Memory Capacity and Cognitive Load on Word Recognition: An Eye Tracking Study

Objectives: The purpose of the study was to identify the impact of age-related working memory capacity and cognitive load to word recognition using an eye tracker.Methods: A total of 48 participants (24 young, 24 elderly adults) who were divided according to working memory capacity (high, low) participated in the study. This study consisted of a digit load and word recognition task.Results: First, the elderly group had lower accuracy and slower response times than the young group. There was a significant difference between working memory capacity and cognitive load in response time. In the group with low working memory capacity, the response time increased under lower cognitive load, which was different from the group with a high working memory capacity. Next, the elderly group had a lower proportion of fixation than the young group by time interval. In addition, there was a significant interaction between group and cognitive load by time interval. In particular, the proportion of fixation decreased over time under a high cognitive load while the proportion of fixation increased under a low cognitive load in the elders, because the inhibition and switching abilities were weakened which made the elders unable to process information efficiently.Conclusion: The study results showed significant effects between working memory capacity and cognitive load in response time and proportion of fixation. This implies that complex factors influence language processing, which makes measuring accuracy insufficient. Thus, this research confirms the correlation among aging, working memory, and cognitive load through both online and offline measurement.

Tailoring explicit and implicit instruction methods to the verbal working memory capacity of students with special needs can benefit motor learning outcomes in physical education

This study examined the effects of explicit versus implicit instructions and feedback methods on motor learning and perceived competence of 9-to 13-year old students with special educational needs practicing a balancing task during physical education. The aim was to test if and how the effects of type of instruction and feedback methods were influenced by students' verbal and visuospatial working memory capacities. The students significantly increased their balancing performance and perceived competence from pre- to posttest, with no differences between groups. The relation between type of instruction and feedback methods and learning outcomes was significantly influenced by verbal working memory capacity, not by visuospatial working memory capacity. Physical education teachers may need to align their instructions with verbal working memory capacity, by providing implicit instructions and feedback methods in students with low verbal working memory capacity and explicit instruction and feedback methods in students with high verbal working memory capacity.

Impact of translation difficulty and working memory capacity on processing of translation units: evidence from Chinese-to-English translation

ABSTRACT This study aims to examine how the source text’s (ST) translation difficulty and subject’s working memory (WM) capacity impact the number and size of translation units (TUs). Based on the data collected through key-logging of 38 students translating two relatively easy and difficult texts, the number of production TUs (PTU) at all levels and sizes of average production TU (APTU) were calculated and compared. It was found that while translating the difficult text, the subjects used more 1-to-6-word TUs, but their APTU sizes were not clearly reduced. The number of PTUs at each level did not vary with WM capacity in the translation of either the easy or the difficult text, but the APTU size of subjects with high WM capacity was larger than that of those with low WM capacity. However, in the translation of the difficult text, the size of APTU of subjects with high WM capacity was significantly reduced compared to those with low WM capacity, thus neutralizing the difference between the two groups in the translation of the relatively easy text.

Interacting effects of frontal lobe neuroanatomy and working memory capacity to older listeners' speech recognition in noise

Many older adults are struggling with understanding spoken language, particularly when background noise interferes with comprehension. In the present study, we investigated a potential interaction between two well-known factors associated with greater speech-in-noise (SiN) reception thresholds in older adults, namely a) lower working memory capacity and b) age-related structural decline of frontal lobe regions.In a sample of older adults (N = 25) and younger controls (N = 13) with normal pure-tone thresholds, SiN reception thresholds and working memory capacity were assessed. Furthermore, T1-weighted structural MR-images were recorded to analyze neuroanatomical traits (i.e., cortical thickness (CT) and cortical surface area (CSA)) of the cortex.As expected, the older group showed greater SiN reception thresholds compared to the younger group. We also found consistent age-related atrophy (i.e., lower CT) in brain regions associated with SiN recognition, namely the superior temporal lobe bilaterally, the right inferior frontal and precentral gyrus, as well as the left superior frontal gyrus. Those older participants with greater atrophy in these brain regions showed greater SiN reception thresholds. Interestingly, the association between CT in the left superior frontal gyrus and SiN reception thresholds was moderated by individual working memory capacity. Older adults with greater working memory capacity benefitted more strongly from thicker frontal lobe regions leading to better SiN recognition.Overall, our results fit well into the literature showing that age-related structural decline in auditory- and cognition-related brain areas is associated with greater SiN reception thresholds in older adults. However, we highlight that this association changes as a function of individual working memory capacity. We therefore believe that future interventions to improve SiN recognition in older adults should take into account the role of the frontal lobe as well as individual working memory capacity.

The Working Memory Network and Its Association with Working Memory Performance in Survivors of non-CNS Childhood Cancer

ABSTRACT Childhood cancer and its treatment puts survivors at risk of low working memory capacity. Working memory represents a core cognitive function, which is crucial in daily life and academic tasks. The aim of this functional MRI (fMRI) study was to examine the working memory network of survivors of childhood cancer without central nervous system (CNS) involvement and its relation to cognitive performance. Thirty survivors (aged 7–16 years, ≥ 1 year after cancer treatment) and 30 healthy controls performed a visuospatial working memory task during MRI, including a low- and a high-demand condition. Working memory performance was assessed using standardized tests outside the scanner. When cognitive demands increased, survivors performed worse than controls and showed evidence for slightly atypical working memory-related activation. The survivor group exhibited hyperactivation in the right-hemispheric superior parietal lobe (SPL) in the high- compared to the low-demand working memory condition, while maintaining their performance levels. Hyperactivation in the right SPL coincided with poorer working memory performance outside the scanner in survivors. Even in survivors of childhood cancer without CNS involvement, we find neural markers pointing toward late effects in the cerebral working memory network. Abbreviations fMRI: Functional magnetic resonance imaging; CNS: Central nervous system; MNI: Montreal Neurological Institute; SES: Socioeconomic status; SPL: Superior parietal lobe

Impact of tDCS on working memory training is enhanced by strategy instructions in individuals with low working memory capacity

Interventions to improve working memory, e.g. by combining task rehearsal and non-invasive brain stimulation, are gaining popularity. Many factors, however, affect the outcome of these interventions. We hypothesize that working memory capacity at baseline predicts how an individual performs on a working memory task, by setting limits on the benefit derived from tDCS when combined with strategy instructions; specifically, we hypothesize that individuals with low capacity will benefit the most. Eighty-four participants underwent two sessions of an adaptive working memory task (n-back) on two consecutive days. Participants were split into four independent groups (SHAM vs ACTIVE stimulation and STRATEGY vs no STRATEGY instructions). For the purpose of analysis, individuals were divided based on their baseline working memory capacity. Results support our prediction that the combination of tDCS and strategy instructions is particularly beneficial in low capacity individuals. Our findings contribute to a better understanding of factors affecting the outcome of tDCS when used in conjunction with cognitive training to improve working memory. Moreover, our results have implications for training regimens, e.g., by designing interventions predicated on baseline cognitive abilities, or focusing on strategy development for specific attentional skills.

Mathematical reasoning structure of junior high school students in solving problems based on their working memory capacity

Mathematical reasoning has a clear structure. In mathematical reasoning structure, working memory capacity is considered as something important. This study aimed at knowing the mathematical reasoning structure of junior high school students in solving problems reviewed based on working memory capacity. This research was a qualitative research. This study was carried out in state Junior High School in Makale. The selection of research subjects was done by providing tests to measure students’ working memory capacity. The test used was O-SPAN Test and the researcher chose 1 student with high category working memory capacity and 1 student with low category working memory capacity. Then the researcher gave a test to investigate the reasoning structure. Mathematical reasoning structure of research participant with low working memory capacity showed the stage of problematic situation, strategy choice, conclusion could be done. However, for the stage of strategy is implemented, subject implemented the strategy in one way and could not find a maximum result. Subject with low working memory capacity could provide conclusions but could not give verification arguments showing the strategy used was correct or reasonable and could solve the problem. Mathematical reasoning structure of research subject with high working memory capacity fulfilled the four mathematical reasoning structures namely problematic situation, strategy choice, implemented strategy, and conclusion.

METACOGNITIVE INTERVENTION AND AWARENESS: LISTENERS WITH LOW WORKING MEMORY CAPACITY

ABSTRACT This study investigated the effect of the Metacognitive Intervention (MI) on the listening performance and metacognitive awareness of upper-intermediate learners of English as a Foreign Language (EFL) with low Working Memory Capacity (WMC). 136 male learners aged between 15 and 25 years formed the original pool of this study, and 94 were identified as upper-intermediate learners learning English at the English Language Institute (ELI) in Iran. They were further given the visual Digit Span Test (DST). Based on their scores and the median, 60 low-WMC learners were selected and randomly assigned to experimental (N = 30) and control (N = 30) groups. The experimental group received the MI through the pedagogical cycle for 10 sessions, whereas the control group followed a traditional approach. The participants in both groups were asked to take the International English Language Testing System (IELTS) listening tests and complete the Metacognitive Awareness Listening Questionnaire (MALQ) before and after the intervention. The results suggested that the experimental group had a higher gain with a moderate effect size in terms of listening performance than the control group. In addition, the MALQ revealed the significantly higher use of directed attention, mental translation, and person knowledge by the experimental group.

Neural Correlates of Mental Rotation in Preschoolers With High or Low Working Memory Capacity: An fNIRS Study.

This study explored the differentiated neural correlates of mental rotation (MR) in preschoolers with high and low working memory capacity using functional near-infrared spectroscopy (fNIRS). Altogether 38 Chinese preschoolers (M = 5.0 years, SD = 0.69 years) completed the Working Memory Capacity (WMC) test, the Mental Rotation (MR), and its Control tasks (without MR). They were divided into High-WMC (N1 = 9) and Low-WMC (N2 = 18) groups based on the WMC scores. The behavioral and fNIRS results indicated that: (1) there were no significant differences in MR task performance between the High-WMC (Mmr = 23.44, SD = 0.88) and Low-WMC group (Mmr = 23.67, SD = 0.59); (2) the Low-WMC group activated BA6, BA8, BA 9, and BA 44, whereas the High-WMC group activated BA8, BA10 and BA 44 during mental rotation; (3) significant differences were found in the activation of BA44 and BA9 between the High-WMC and Low-WMC groups during mental rotation; and (4) the High-WMC and Low-WMC groups differed significantly in the activation of BA 9 and BA10 during the control tasks, indicating that both areas might be responsible for the group differences in working memory.

Do working memory capacity and test anxiety modulate the beneficial effects of testing on new learning?

Although testing has repeatedly been shown to be one of the most effective strategies for consolidating retention of studied information (the backward testing effect) and facilitating mastery of new information (the forward testing effect), few studies have explored individual differences in the beneficial effects of testing. The current study recruited a large sample (1,032 participants) to explore the potential roles of working memory capacity and test anxiety in the enhancing effects of testing on new learning, and the converse influence of testing on test anxiety. The results demonstrated that administering interim tests during learning appears to be an effective technique to potentiate new learning, regardless of working memory capacity and test anxiety. At a final test on all studied materials, individuals with low working memory capacity benefited more from interim testing than those with high working memory capacity. These testing effects are minimally modulated by levels of trait/state test anxiety, and low-stake interim testing neither reduced nor increased test anxiety. Overall, the results imply that low-stake interim tests can be administered to boost new learning irrespective of learners' level of WMC, test anxiety, and of possible reactive effects of testing on test anxiety. (PsycInfo Database Record (c) 2020 APA, all rights reserved).