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Visual working memory (VWM) refers to the temporary storage and manipulation of visual information. Although visually different, objects we view and remember can share the same higher-level category information, such as an apple, orange, and banana all being classified as fruit. We study the influence of category information on VWM, focusing on the question of whether stimulus category coherence (i.e., whether all to-be-remembered items belong to the same semantic category) influences VWM performance. This question is addressed in two behavioral experiments using a change-detection paradigm and a rational analysis using an ideal observer based on a Bayesian model. Both experimental participants and the ideal observer often, but not always, performed numerically better on coherent trials (i.e., when all stimuli belonged to the same category). We hypothesize that the influence of category coherence information on VWM may be task-dependent and/or stimulus-dependent. In conditions when category coherence information is highly valuable for task performance, as indicated by the ideal observer, then participants tended to make use of it. However, when the ideal observer suggested this information was not crucial to performance, participants did not. In addition, both participants and the ideal observer showed a bias toward responding "same," and often showed a stronger influence of category coherence on change trials. The consistencies between participant and ideal observer responses suggest participants often behaved as they did because these behaviors are optimal (or approximately so) for maximizing task performance. This may help explain conflicting results reported in the scientific literature.

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Working memory capacity (WMC) refers to the ability to maintain information in short-term memory while attending to the immediate environment, and has been associated with emotional states. Yet, research on the link between WMC and emotion in naturalistic settings is growing and inconsistencies have been observed. In the current study (N = 109), we directly replicated the procedures of a prior experience sampling study (Garrison & Schmeichel, 2022), which found that higher WMC attenuates the relationship between stressful events in daily life and negative affect. We measured WMC in the laboratory and then measured the occurrence of stressful events, momentary emotional states, and coping responses to stress several times a day for six days. Higher WMC was associated with reduced momentary negative emotion, but this relationship did not depend on the occurrence of a stressful event. Exploratory analyses found that higher WMC was associated with a greater likelihood of planning as a coping response to stress and greater number of coping strategies reported per stressful event. However, coping did not mediate the link between WMC and momentary negative emotion. Our results contribute to the robustness and ecological validity of the link between WMC and reduced negative emotion in daily life.

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Working memory is the fundamental function of the various cognitive processes and abilities in the overall trajectory of development. Significant advances in multivariate analysis of human functional magnetic resonance imaging data have converged functional segregation models toward integrated representation-based models. However, due to the inherent limitations of the multi-voxel pattern analysis method, we are unable to determine whether the underlying neural representations are spatially similar in the brain. Our study attempts to answer this question by examining the spatial similarity of brain activity during the working memory task in children and adults. Our results reveal similar patterns of activity between the regions involved in working memory. This functional network of similar spatial patterns was observed in both normally developing children and adults. However, the between-region similarity was more pronounced in adults than in children and associated with better performance. We propose an exchange of similar information flows through the brain at an integrated level of working memory processes, underpinning the holistic nature of working memory representation.

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We commonly load visual working memory minimally when to-be-remembered information remains available in the external world. In visual search, this is characterised by participants frequently resampling previously encoded templates, which helps minimize cognitive effort and improves task performance. If all search templates have been rehearsed many times, they should become strongly represented in memory, possibly eliminating the benefit of reinspections. To test whether repetition indeed leads to less resampling, participants searched for sets of 1, 2, and 4 continuously available search templates. Critically, each unique set of templates was repeated 25 trials consecutively. Although the number of inspections and inspection durations initially decreased strongly when a template set was repeated, behaviour largely stabilised between the tenth and last repetition: Participants kept resampling templates frequently. In Experiment 2, participants performed the same task, but templates became unavailable after 15 repetitions. Strikingly, accuracy remained high even when templates could not be inspected, suggesting that resampling was not strictly necessary in later repetitions. We further show that seemingly 'excessive' resampling behaviour had no direct within-trial benefit to speed nor accuracy, and did not improve performance on long-term memory tests. Rather, we argue that resampling was partially used to boost metacognitive confidence regarding memory representations. As such, eliminating the benefit of minimizing working memory load does not eliminate the persistence with which we sample information from the external world - although the underlying reason for resampling behaviour may be different.

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Introduction: Working memory (WM) as one of the executive functions is an essential neurocognitive ability for daily life. Findings have suggested that aging is often associated with working memory and neural decline, but the brain structures and resting-state brain networks that mediate age-related differences in WM remain unclear. Methods: A sample consisting of 252 healthy participants in the age range of 20 to 70years was used. Several cognitive tasks, including the n-back task and the forward and backward digit span tests were used. Also, resting-state functional imaging, as well as structural imaging using a 3T MRI scanner, were performed, resulting in 85 gray matter volumes and five resting-state networks, namely the anterior and posterior default mode, the right and left executive control, and the salience networks. Also, mediation analyses were used to investigate the role of gray matter volumes and resting-state networks in the relationship between age and WM. Results: Behaviorally, aging was associated with decreased performance in the digit span task. Also, aging was associated with a decreased gray matter volume in 80 brain regions, and with a decreased activity in the anterior default mode network, executive control, and salience networks. Importantly, the path analysis showed that the GMV of the medial orbitofrontal, precentral, parieto-occipital, amygdala, middle occipital, posterior cingulate, and thalamus areas mediated the age-related differences in the forward digit span task, and the GMV of superior temporal gyrus mediated the age-related differences in the backward digit span task. Discussion: This study identified the brain structures mediating the relationship between age and working memory, and we hope that our research provides an opportunity for early detection of individuals at risk of age-related memory decline.

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Social hierarchies exist in all societies and impact cognitive functions, brain mechanisms, social interactions, and behaviors. High status individuals often exhibit enhanced working memory (WM) performance compared to lower status individuals. This study examined whether individual differences in social dominance, as a predictor of future status, relate to WM abilities. Five hundred and twenty-five students completed the Personality Research Form dominance subscale questionnaire. From this sample, students with the highest and lowest scores were invited to participate in the study. Sixty-four participants volunteered to take part and were subsequently categorized into high- and low-dominance groups based on their dominance subscale questionnaire (PRF_d) scores. They performed a Sternberg WM task with set sizes of 1, 4, or 7 letters while their EEG was recorded. Event-related potential (ERP) and power spectral analysis revealed significantly reduced P3b amplitude and higher event-related synchronization (ERS) of theta and beta during encoding and retrieval phases in the high-than low-dominance group. Despite these neural processing differences, behavioral performance was equivalent between groups, potentially reflecting comparable cognitive load demands of the task across dominance levels. Further, there were similar P3b patterns for each set-size within groups. These findings provide initial evidence that individual differences in social dominance trait correlate with WM functioning, as indexed by neural processing efficiency during WM performance.

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The ability to prepare and maintain an optimal level of preparedness for action, across some unknown duration, is critical for human behavior. Temporal preparation has historically been analyzed in the context of reaction time (RT) experiments where the interval varies between the start of the trial, or foreperiod (FP), and the required response. Two main findings have come out of such paradigms: the variable FP effect (longer RTs to shorter vs. longer FPs) and the sequential FP effect (longer RTs when shorter FPs follow longer FPs). Several theoretical views of these FP effects have been proposed with some suggesting a dissociation while others argue for an implicit process driven by memory traces. One possible method to test these views of FP effects is to examine how individual differences in working memory capacity (WMC) moderate such effects. To this end, I reanalyzed data from three studies in which participants completed measures of WMC and a simple RT task with a variable FP. Results suggest that individual differences in WMC were related to the magnitude of the variable FP and the sequential FP effect in two of three individual studies. A "mega-analysis" provided supportive evidence for a relationship between WMC and both forms of FP effects. The present combined experimental-individual differences study provides a novel approach to better understand how and why individuals vary in temporal preparation ability. Through leveraging several large-scale databases unseen in FP research, I provide a new way of understanding FP effects and response timing more generally.

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In order to understand how prefrontal cortex provides the benefits of working memory (WM) for visual processing we examined the influence of WM on the representation of visual signals in V4 neurons in two macaque monkeys. We found that WM induces strong ß oscillations in V4 and that the timing of action potentials relative to this oscillation reflects sensory information- i.e., a phase coding of visual information. Pharmacologically inactivating the Frontal Eye Field part of prefrontal cortex, we confirmed the necessity of prefrontal signals for the WM-driven boost in phase coding of visual information. Indeed, changes in the average firing rate of V4 neurons could be accounted for by WM-induced oscillatory changes. We present a network model to describe how WM signals can recruit sensory areas primarily by inducing oscillations within these areas and discuss the implications of these findings for a sensory recruitment theory of WM through coherence.

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Ischemic stroke is followed by an increased susceptibility to bacterial infections, which exacerbate histological stroke outcome, neurological deficits and memory impairment due to increased neuroinflammation and neurotransmitter dysfunction. Pharmacological activation of nicotinic acetylcholine receptors was suggested to mitigate brain inflammatory responses in ischemic stroke. The functional responses associated with nicotinic acetylcholine receptor activation were unknown. In this study, male NMRI mice subjected to transient intraluminal middle cerebral artery occlusion (MCAO) were intraperitoneally exposed to vehicle treatment or Escherichia coli lipopolysaccharide (LPS; 4 mg/kg)-induced sepsis-like state 24 h post-MCAO, followed by intraperitoneal administration of vehicle or nicotine (0.5 mg/kg) 30 min later. Over 96 h, rectal temperature, neurological deficits, spontaneous locomotor activity, working memory, ischemic injury, synaptic plasticity, and brain inflammatory responses were evaluated by temperature measurement, behavioral analysis, infarct volumetry, electrophysiological recordings, and polymerase-chain reaction analysis. LPS-induced sepsis induced hypothermia, increased general and focal neurological deficits, reduced spontaneous exploration behavior, reduced working memory, and increased infarct volume post-MCAO. Additional treatment with nicotine attenuated LPS-induced hypothermia, reduced neurological deficits, restored exploration behavior, restored working memory, and reduced infarct volume. Local field potential recordings revealed that LPS-induced sepsis decreased long-term potentiation (LTP) in the dentate gyrus post-MCAO, whereas concomitant nicotine exposure restored LTP in the contralateral dentate gyrus. LPS-induced sepsis increased microglial/ macrophage Iba-1 mRNA and astrocytic GFAP mRNA levels post-MCAO, whereas add-on nicotine treatment reduced astrocytic GFAP mRNA. Taken together, these findings indicate that acute nicotine exposure enhances functional stroke recovery. Future studies will have to evaluate the effects of (1) chronic nicotine exposure, a clinically relevant vascular risk factor, and (2) the cessation of nicotine exposure, which is widely recommended post-stroke, but might have detrimental effects in the early stroke recovery phase.

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During visual search, representations in working memory (WM) can guide the deployment of attention toward memory-matching visual input. Although previous studies have demonstrated that multisensory interactions facilitate WM and visual search, it remains unclear whether multisensory interaction influences attentional capture by WM. To address this issue, the present study adopted a dual-task paradigm, pairing a visual search task with a WM task, in which the memory modality was manipulated to be either visual or audiovisual. The results revealed that memory-driven attentional capture was observed under the visual and the audiovisual condition. Additionally, the capture effects and response time (RT) costs under the audiovisual condition were weaker than those under the visual condition, even on the trials with the earliest RTs. Furthermore, RT benefits under the audiovisual condition were comparable with those under the visual condition. These findings suggest that multisensory interactions can enhance cognitive control, leading to robust strategic effects and improved search performance. In this process, cognitive control tends to suppress the attentional capture by WM-matching distractors rather than enhance the attentional capture by WM-matching targets. The present study offers new insights into the influence of multisensory interactions on attentional capture by WM.

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This study aimed to analyze the frequency of unexpected subclinical spikes (USCS) in pediatric patients who underwent high-density electroencephalogram (HD-EEG). Of the 4481 successful HD-EEG studies, 18.5% (829) were abnormal, and 49.7% of these abnormal studies showed SCS, of which 64.1% were USCS. USCS were found to be correlated with attention/concentration deficits and executive dysfunction, often accompanied by the dual psychiatric diagnosis of ADHD. MRI revealed abnormal findings in 32.6% of the subjects with USCS, such as abnormal signal or signal hyperintensity in brain parenchyma, temporal or arachnoid cysts, and vascular malformations. Moreover, the USCS group who received neuropsychiatric testing scored lower than the population mean on Full-Scale Intelligence Quotient, Working Memory Index, and Processing Speed Index. This study highlights the potential of USCS as biomarkers that can lead to changes in clinical management and outcomes, provide valuable information about pathophysiological mechanisms, and suggest potential treatment pathways.

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OBJECTIVE: To investigate the neural mechanisms underlying working memory (WM) deficits in children with ADHD. METHOD: WM was compared between thirty-four children with ADHD and thirty-four matched controls using neuropsychological tests, spatial and verbal versions of modified delayed matching-to-sample (DMTS) tasks, and the event-related potential technique. RESULTS: Children with ADHD demonstrated poor behavioral performance, delayed P3 latencies in high-load spatial modified DMTS tasks during encoding, and delayed P2 and N2 latencies during retrieval in spatial modified DMTS tasks. In high-load verbal modified DMTS tasks during encoding, they showed a smaller P3 amplitude. DISCUSSION: Pronounced deficits in the central executive system in children with ADHD were exhibited by neuropsychological tests and the modified DMTS task. Children with ADHD exhibited a slowing of processing speed during encoding. Under high-load conditions, they showed a reduced P3 amplitude during retrieval, suggesting reduced neural resource allocation was available when the central executive of the working memory was heavily loaded.

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

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With the increasing aging population, contemporary society faces the imperative to develop approaches that efficiently delay the age-related decline in working memory capacity, which is a critical area within cognitive aging research. Nevertheless, there is insufficient evidence to support the efficacy of verbal working memory training across various sensory modalities (visual, auditory, and audiovisual) in enhancing the verbal working memory capacity of older adults. In this study, 60 healthy older adults (mean age = 67.07 ± 3.79 years, comprising 34 women and 26 men, mean education = 15.55 ± 2.53 years) were randomly assigned to one of four groups: visual verbal working memory (V-VWM) group, auditory verbal working memory (A-VWM) group, visual-auditory verbal working memory (VA-VWM) group, and a control group. The training duration spanned 12 days. We also investigated whether baseline level and education predicted the outcomes. Findings indicated that V-VWM training had a large effect on improving V-VWM task performance (Cohen's d = 1.765), A-VWM training showed a substantial effect on A-VWM task performance (Cohen's d = 1.904), and VA-VWM training demonstrated a significant effect on VA-VWM task performance (Cohen's d = 2.319) over pretest scores in older adults. Enhancements achieved through V-VWM training exhibited near transfer effects, improving performance in both A-VWM and VA-VWM tasks. In contrast, gains from A-VWM training were selectively transferred to the VA-VWM task. Furthermore, VA-VWM training led to improvements not only in V-VWM and A-VWM tasks but also extended to verbal operation span task with a significant 29.7 % increase. However, no significant transfer effects were observed for the DSF and DSB tasks across the three training groups. The maintenance effect of VA-VWM training persisted for two weeks across tasks involving VA-VWM, V-VWM, and A-VWM. The baseline of VWM span score influence the effect of V-VWM training and transfer effect of VA-VWM training. Education level did not predict the training effects of V-VWM, A-VWM, and VA-VWM. These findings highlight the nuanced effects of sensory-specific verbal working memory training in older adults, emphasizing the potential of tailored interventions to enhance specific aspects of cognitive function, while also highlighting the promising applications of mobile device training in enhancing cognitive skills among the elderly.

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Network neuroscience explores the brain's connectome, demonstrating that dynamic neural networks support cognitive functions. This study investigates how distinct cognitive abilities-working memory and cognitive inhibitory control-are supported by unique brain network configurations constructed by estimating whole-brain networks using mutual information. The study involved 195 participants who completed the Sternberg Item Recognition task and Flanker tasks while undergoing electroencephalography recording. A mixed-effects linear model analyzed the influence of network metrics on cognitive performance, considering individual differences and task-specific dynamics. The findings indicate that working memory and cognitive inhibitory control are associated with different network attributes, with working memory relying on distributed networks and cognitive inhibitory control on more segregated ones. Our analysis suggests that both strong and weak connections contribute to cognitive processes, with weak connections potentially leading to a more stable and support networks of memory and cognitive inhibitory control. The findings indirectly support the network neuroscience theory of intelligence, suggesting different functional topology of networks inherent to various cognitive functions. Nevertheless, we propose that understanding individual variations in cognitive abilities requires recognizing both shared and unique processes within the brain's network dynamics.

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In four experiments, we describe the first finding of a Metrical Hebb Effect. Participants are shown to exhibit a Hebb Repetition Effect for repeating, list-wide stress patterns across sequences of familiar words, even though the lexical items within the "repeating" lists do not themselves repeat. Experiment 1 established the presence of a Hebb effect for metrical patterns, demonstrating significant learning of list-wide metrical patterns over successive presentations. Experiment 2 investigated the effect's longevity, showing persistence of learned metrical information after a spacing of three non-repeating lists. Experiment 3 revealed that the effect did not persist over a longer spacing, of eight intervening lists. Experiment 4 investigated the learning mechanism, suggesting that chunking, rather than item-position binding, might account for the observed learning of metrical patterns. The authors propose that metrical-pattern learning represents a process of gradual integration of sequences of weak and strong stress accents, into higher-level units representing the stress patterns within, and across, words. We briefly discuss some implications of the Metrical Hebb Effect for phonological word-form learning, and for speech perception and production.

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Using a person-centered approach, we aimed to identify different executive functioning profiles to assess heterogeneity across individuals within the same school grade through latent profile analysis. A sample of 150 Grade 2 (7-8 years old), 150 Grade 6 (11-12 years old), and 150 Grade 10 (15-16 years old) children and adolescents were assessed on 11 different executive tasks representative of the three main executive functioning subcomponents (i.e., inhibition, cognitive flexibility, and working memory), fluid intelligence, processing speed, problem-solving, and reading comprehension. Three different executive functioning profiles of different patterns of interactions based on inhibition, cognitive flexibility, and working memory within and between grades were identified. Moreover, these profiles were differentially related to reading comprehension and mathematical achievement. Second, as expected, we did not find these profiles to be associated with sociodemographic variables such as chronological age or sex. Still, fluid intelligence and processing speed were differentially related to the different profiles at each grade. We also found that the executive functioning profiles interacted with each cognitive skill (i.e., fluid intelligence and processing speed) in predicting reading comprehension and math achievement. These findings provide valuable insights for developing preventive and intervention strategies in education.

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Theories of visual working memory have seen significant progress through the use of continuous reproduction tasks. However, these tasks have mainly focused on studying visual features, with limited examples existing in the auditory domain. Therefore, it is unknown to what extent newly developed memory models reflect domain-general limitations or are specific to the visual domain. To address this gap, we developed a novel methodology: the Auditory Reproduction Task (ART). This task utilizes Shepard tones, which create an infinite rising or falling tone illusion by dissecting pitch chroma and height, to create a 1-360° auditory circular space. In Experiment 1, we validated the perceptual circularity and uniformity of this auditory stimulus space. In Experiment 2, we demonstrated that auditory working memory shows similar set size effects to visual working memory-report error increased at a set size of 2 relative to 1, caused by swap errors. In Experiment 3, we tested the validity of ART by correlating reproduction errors with commonly used auditory and visual working memory tasks. Analyses revealed that ART errors were significantly correlated with performance in both auditory and visual working memory tasks, albeit with a stronger correlation observed with auditory working memory. While these experiments have only scratched the surface of the theoretical and computational constraints on auditory working memory, they provide a valuable proof of concept for ART. Further research with ART has the potential to deepen our understanding of auditory working memory, as well as to explore the extent to which existing models are tapping into domain-general constraints.

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EFL listening comprehension has been a stark challenge for language learners, but little is known about the combined effect of individual differences, such as working memory capacity, and metacognitive intervention. Thus, the present experimental study investigates the effect of metacognitive intervention on the listening performance and metacognitive awareness of high- and low-WMC EFL learners. For this purpose, Oxford Placement Tests were distributed among 120 male Iranian EFL learners, of which 94 were identified as intermediate. Then, backward visual digit span tests were administered to measure their working memory capacity. Based on the median of all scores, 80 learners were selected and randomly assigned to two experimental groups and two control groups each with 20 participants. Next, their performance on the International English Language Testing System and the Metacognitive Awareness Listening Questionnaire was measured before and after the 8-session metacognitive intervention. Results showed that high-WMC experimental learners had a higher gain with a large effect size in terms of listening performance compared with all the other groups. In addition, the experimental group learners reported the significantly higher use of the metacognitive strategies with a moderate effect size. Interestingly, low-WMC learners' listening performance and metacognitive awareness also improved as a result of the intervention. Our findings bear pedagogical significance in that individual differences in WMC should be considered more in both EFL language classes and the future line of research involving the metacognitive intervention.

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The Tactual Span assesses tactile working memory (WM) using both hands while applying forward and backward conditions. The study objectives were to validate a one-hand version of the Tactual Span and to evaluate WM laterality in the tactile modality. Of the 145 participants, 80 performed the Tactual Span with their right hand, and 65 performed it with their left hand. Moreover, all participants performed two span tasks in the visuo-spatial and auditory modalities, each encompassing forward and backward conditions. Results revealed adequate Cronbach's alpha values for each hand in both conditions of the Tactual Span, along with a positive correlation between forward and backward conditions in each hand. However, overall performance on the Tactual Span was poorer compared to performance on the Auditory and Visuo-spatial Spans. Furthermore, in the forward condition, there was a correlation between the Auditory Span and the Tactual Span, but only for the right hand. In the backward condition, the Auditory Span correlated with the Tactual Span in both hands. The findings indicate that there is no effect of hand laterality in tactile WM, showing the two hands are related to each other in their WM function. Additionally, the one-hand version of the Tactual Span is deemed useful for evaluating tactile WM and can therefore be used in empirical and clinical settings for neuropsychological assessment purposes.