Increases in intrusion errors and working memory deficit of poor comprehenders

Control of bottom-up attention in scene cognition contributes to visual working memory performance

Several studies have investigated the relationship between working memory and attention. However, most of the relevant studies so far investigated top-down attention; only a few have examined possible interactions between bottom-up attention and visual working memory. In the present study, we focused on the visual saliency of different parts of pictures as an index of the degree to which one's bottom-up attention can be drawn towards each of them. We administered the Picture Span Test (PST) to investigate whether salient parts of pictures can influence the performance of visual working memory. The task required participants to judge the semantic congruency of objects in pictures and remember specific parts of pictures. In Experiment 1, we calculated a saliency map for the PST stimuli and found that salient but task-irrelevant parts of pictures could evoke intrusion errors. In Experiment 2, we demonstrated that longer gazing time at target areas results in a higher probability of making correct recognition. In addition, frequent gaze fixation and high normalized scan-path saliency values in task-irrelevant areas were associated with intrusion errors. These results suggest that visual information processed by bottom-up attention may affect working memory.

The relationship between mind wandering and reading comprehension: A meta-analysis

Mind wandering (MW), a shift of attention away from external tasks toward internally generated thoughts, has been frequently associated with costs in reading comprehension (RC), although with some contrasting results and many reported potential intervening factors. The aim of the meta-analysis was to evaluate the relationship between MW and RC, considering the role of participants' and text's characteristics, as well as methodological issues in the measurement of the two constructs. From a set of 25 selected full texts (73 correlation coefficients), pooled correlation (r = -0.21) revealed a negative significant relationship. Using trait-based questionnaires to assess MW compared with online probes resulted in an average significant change of 0.30 in the correlation between MW and RC, leading to a null correlation. A significant effect of age was also found, with more negative correlations with increasing age. None of the other moderating variables considered (i.e., language, text type, text length, RC assessment, text difficulty, text interest, and working memory) resulted in a significant effect. From the present meta-analysis, we might suggest that MW and RC are partially overlapping and vary, within a swing effect, in relation to a set of shared factors, such as working memory, interest, and text length. There might also be side-specific factors that drive the movement of primarily one side of the swing, and future research should further consider the role of individual differences in RC. Implications for research and educational settings are discussed.

Saccade rate is associated with recall of items in working memory

Working memory has been shown to rely on theta oscillations' phase synchronicity for item encoding and recall. At the same time, saccadic eye movements during visual exploration have been observed to trigger theta-phase resets, raising the question of whether the neuronal substrates of mnemonic processing rely on motor-evoked responses. To quantify the relationship between saccades and working memory load, we recorded eye tracking and behavioral data from human participants simultaneously performing an n-back Sternberg auditory task and a hue-based catch detection task. In addition to task-specific interference in performance, we also found that saccade rate was modulated by working memory load in the Sternberg task's preresponse stage. Our results support the possibility of interplay between saccades and hippocampal theta during working memory retrieval of items.

Working Memory Beats Age: Evidence of the Influence of Working Memory on the Production of Children's Emotional False Memories

Emotional valence and working memory ability (WM) affect false memories’ production in adults. Whereas a number of studies have investigated the role of emotional valence in children’s tendency to produce spontaneous false memories, individual differences in WM have not been previously included. In the current article, we were interested in investigating whether emotion and WM would interact in influencing the propensity to incur inferential false memories for scripted events. Ninety-eight typically developing children (first-, third-, and eighth- graders) were administered the Emotional false memory paradigm – allowing to study false memories for negative, positive, and neutral events – and a WM task. Results showed that regardless of age, valence influenced false memories’ production, such that positive events protected against incurring distortions. Furthermore, WM interacted with valence, such that children with higher WM abilities produced fewer false memories for negative events. Concerning confidence judgments, only the youngest group of children claimed to be overconfident when committing false memories for negative and neutral events. Results are discussed in terms of the role of individual differences in higher cognitive abilities interacting with the emotional content of to-be-remembered events.

Individual Differences in Inhibitory Control: A latent Variable Analysis

Inhibitory control represents a central component of executive functions and focuses on the ability to actively inhibit or delay a dominant response to achieve a goal. Although various tasks exist to measure inhibitory control, correlations between these tasks are rather small, partly because of the task impurity problem. To alleviate this problem, a latent variable approach has been previously applied and two closely related yet separable functions have been identified: prepotent response inhibition and resistance to distractor interference. The goal of our study was a) to replicate the proposed structure of inhibitory control and b) to extend previous literature by additionally accounting for speed-accuracy trade-offs, thereby potentially increasing explained variance in the investigated latent factors. To this end, 190 participants completed six inhibitory control tasks (antisaccade task, Stroop task, stop-signal task, flanker task, shape-matching task, word-naming task). Analyses were conducted using standard scores as well as inverse efficiency scores (combining response times and error rates). In line with previous studies, we generally found low zero-order correlations between the six tasks. By applying confirmatory factor analysis using standard reaction time difference scores, we were not able to replicate a satisfactory model with good fit to the data. By using inverse efficiency scores, a two-related-factor and a one-factor model emerged that resembled previous literature, but only four out of six tasks demonstrated significant factor loadings. Our results highlight the difficulty in finding robust inter-correlations between commonly used inhibitory control tasks, even when applying a latent variable analysis and accounting for speed-accuracy trade-offs.

Mental imagery training in older adults: Which are benefits and individual predictors?

OBJECTIVES

Strategic memory training involves explicit instructions in mnemonic methods to improve recall. Mental imagery is considered among the most effective encoding strategies. The aim of the present study was to assess the benefits of a strategic memory training based on mental imagery (originally proposed by Carretti et al., 2007) and to further investigate its potentials. The study represents a replication in a new and independent cultural setting and features valuable methodological amendments, while it also examines individual predictors of training efficacy.

DESIGN

A sample of 91 older volunteers (age 61-88), divided in training and control group, participated in the training. Specific training gain in the immediate word list recall (criterion task), as well as transfer effects on Letter-Number Sequencing (working memory [WM] task), long-term recall and recognition (LTM tasks) were tested at the pretest and at the posttest.

RESULTS

Analysis of variance showed posttraining effects in immediate word recall and long-term verbal recall, but no effects in WM task and long-term recognition. Regression analysis showed age to be the only significant predictor in one task, the immediate word recall.

CONCLUSIONS

Overall, proposed training can improve some aspects of memory performance by aiding in strategic use of mental imagery. Transfer to other tasks and contribution of individual predictors to training efficacy results limited, however. It seems that training benefits are evident when task similarity enables transfer-appropriate processing (as evidenced in gains of both recall tasks), while training efficacy relies on individual characteristics which contribute to the execution of some task components.

The role of BMI on cognition following acute physical activity in preadolescent children

BACKGROUND

There is an increasing prevalence of physical inactivity during childhood, concurrent with a rise in obesity rates, which is associated with a variety of health problems. However, the extent to which increased body mass index (BMI) influences acute physical activity (PA) benefits on cognition in childhood remains unknown. The aim of this study was to examine whether BMI influences the effects of acute PA on inhibitory control task performance.

METHODS

In a sample of 116 children pooled from four prior studies (ages 8-11; 51 females), demographic measures of age, sex, IQ, socioeconomic status, and aerobic fitness were considered along with BMI. Children participated in a counterbalanced, randomized crossover study, whereby they completed two different interventions; 20 minutes of treadmill walking (60-70% heart rate max) and restful reading (non-exercise control). Following each intervention, children performed a modified flanker task that manipulates inhibitory control demands. Correlations were conducted to determine the influence of demographic variables, fitness, and BMI on inhibitory control following each intervention. Subsequent hierarchical regression analyses were performed with significant demographic factors in the first step, aerobic fitness in the second step when significant, and BMI in the final step.

RESULTS

Analyses indicated that children exhibited improved task performance (p's ≤ 0.001) and decreased interference (p = 0.04) following the walking intervention compared to the restful reading control condition, indicating greater benefits following acute PA across task condition, with selectively greater benefits for the task condition requiring greater inhibitory control. Regression analyses revealed that greater BMI was related to decreased performance following acute PA (p = 0.001); an association not observed following restful reading (p's ≥ 0.11). These results suggest that BMI negatively influences the effect of acute exercise on performance.

CONCLUSION

Confirming previous studies, these findings indicate beneficial effects of acute PA on a flanker task that modulates inhibitory control requirements, but the effects are significantly greater for task conditions requiring greater amounts of inhibitory control. Further, these beneficial effects of PA appear to be blunted in children with higher BMI. These findings suggest that the acute benefits of PA on cognition may not be fully realized in children with higher BMI.

Working memory training format in older adults: individual versus group sessions

Working memory (WM) training has been shown to increase the performance of participants in WM tasks and in other cognitive abilities, but there has been no study comparing directly the impact of training format (individual vs. group) using the same protocol. Therefore, the aim of this study was to compare the efficacy of the Borella et al. three session verbal WM training offered in two different formats on target and transfer tasks. This study was conducted in two waves. In the first wave, participants were randomized into individual training (n = 11) and individual control conditions (n = 15). In the second wave, participants were randomized into group training (n = 16) and group control conditions (n = 17). Training consisted of three sessions of WM exercises and participants in the active control condition responded to questionnaires during the same time. There was significant improvement for both training conditions at post-test and maintenance at follow-up for the target task, other WM tasks, processing speed, and executive functions tasks. The ANOVA results showed that the training gains did not depend on the WM training format. However, the effect size analyses suggested that this intervention can be more effective, at short term and follow-up, when provided individually. To conclude, this study showed that providing this training collectively or individually does not change the training benefits, which increases the possibilities of its use in different contexts.

Electrophysiological correlates of the Categorization Working Memory Span task in older adults

Older adults typically show poor performance in tasks assessing working memory (WM), a crucial cognitive mechanism. The present study examined the electrophysiological correlates of a classic complex WM task often used in studies involving older adults, the Categorization Working Memory Span task (CWMS), by means of event-related potentials. Thirty-five healthy, right-handed older adults (64-75 years) were presented the CWMS task while a 38-channel EEG was measured, and the N1, P1, and word recognition potential (RP) were analyzed on four regions of interest (ROIs) of 5 electrodes each. Additionally, late positive components (P200 and P300) were analyzed in midline ROIs of 3 electrodes each. Participants also executed an n-back task (2-back condition) and an objective performance-based task (the Ability to solve Problems in Everyday life [APE]). At a behavioral level, significant correlations were found between the CWMS, the 2-back, and the APE tests. At a physiological level, N1 and word RP showed greater bilateral amplitude in posterior electrodes, but the better the CWMS and the 2-back performance, the greater the RP amplitude on posterior left sites. The CWMS task induced a clear P200 component, but its amplitude was not correlated with participants' behavioral performance. Altogether, notwithstanding that the bilateral RP pattern elicited by the CWMS is a clear marker of WM processing in older adults, better elderly performers on this complex WM test showed greater left hemisphere dominance to the automatic word RP.

The Contribution of Executive Functions in Predicting Mathematical Creativity in Typical Elementary School Classes: A Twofold Role for Updating

The goal of the current study was to investigate the role of executive functions in mathematical creativity. The sample included 278 primary school children (ages 8–13). Two models were compared: the starting model tested whether executive functions (shifting, updating, and inhibition), domain-general creativity, and mathematical ability directly predicted mathematical creativity. The second model, which fitted the data best, included the additional assumption that updating influences mathematical creativity indirectly through mathematical ability and domain-general creativity. Updating was positively related to mathematical creativity. Additionally, updating was positively related to mathematical ability and domain-general creativity. Inhibition, shifting, domain-general creativity and mathematical ability did not have a significant contribution to either model but did positively correlate with mathematical creativity. This study reports the first empirical evidence that updating is a predictor of mathematical creativity in primary school children and demonstrates that creativity is a higher order cognitive process, activating a variety of cognitive abilities.

Readers Recruit Executive Functions to Self-Correct Miscues During Oral Reading Fluency

Reading fluency undoubtedly underlies reading competence; yet, the role of executive functions (EF) is less well understood. Here, we investigated the relationship between children's reading fluency and EF. Children's (n = 82) reading and language performance was determined by standardized assessments and EF by parental questionnaire. Results revealed that production of more miscues was explained by poorer reading and language performance and EF. Yet, self-correcting a miscue was predicted by better EF, beyond reading and language abilities. Intriguingly, EF partially mediated the relationship between reading and self-correction, suggesting that self-correction reflects parallel recruitment and coordination of domain-specific and domain-general processes.

Verbal working memory training in older adults: an investigation of dose response

The WM training protocol proposed by Borella et al. found specific and transfer effects among seniors, however, the studies were carried out in the same socio-cultural context and variations in the procedure were never tested. The present study aimed at analyzing the efficacy of Borella et al.'s training, in terms of short and long-term benefits, in a different socio-cultural context (Study 1), and the effect of change in the training's length (duplicating the number of sessions (Study 2). Participants were randomly assigned to a trained group (N = 18 for Study 1, and N = 23 for Study 2) and active control group (N = 28 for Study 1, and N = 27 for Study 2), and evaluated at pre, post-test and six-month follow-up for verbal WM task (criterion task), and for visuospatial and verbal WM, inhibition, processing speed, executive function, and fluid intelligence measures (transfer tasks). The trained groups had higher performance in all tasks when compared with active control groups after training and at 6 month follow-up. The longer training (Study 2) generated similar gains as the original protocol, with some advantage in far transfer tasks at post-test and follow-up. Study limitations include the small sample sizes. In conclusion, this training was effective in a different socio-cultural context and adding three sessions to the protocol did not significantly change training impact.

Working memory, negative affect and personal assets: How do they relate to mathematics and reading literacy?

Introduction

Research has recently focused on the relationships between working memory, negative affect (e.g., general anxiety, depressive symptoms) and personal assets (e.g., self-concept, academic and competence dimensions, and ego-resiliency), and their influence on mathematics and reading literacy. Although these variables have been amply explored, previous research has usually considered each of these aspects in isolation.

Method

In the present study, 143 schoolchildren in sixth to eighth grade were tested on general anxiety, depressive symptoms, working memory, self-concept (academic and competence scales), ego-resiliency, and mathematics and reading literacy.

Results

Variance partitioning showed that all predictors, i.e., working memory, negative affect (i.e., general anxiety and depressive symptoms), and personal assets (i.e., self-concept, academic and competence dimensions, and ego-resiliency) explained a unique and shared portion of the variance in mathematics and reading literacy.

Conclusions

Our findings point to the importance of investigating the relationship between these factors. Underlying implications and directions for future research are discussed.

Cognitive and Personality Components Underlying Spoken Idiom Comprehension in Context. An Exploratory Study

In this exploratory study, we investigated whether and to what extent individual differences in cognitive and personality variables are associated with spoken idiom comprehension in context. Language unimpaired participants were enrolled in a cross-modal lexical decision study in which semantically ambiguous Italian idioms (i.e., strings with both a literal and an idiomatic interpretation as, for instance, break the ice), predictable or unpredictable before the string offset, were embedded in idiom-biasing contexts. To explore the contributions of different cognitive and personality components, participants also completed a series of tests respectively assessing general speed, inhibitory control, short-term and working memory, cognitive flexibility, crystallized and fluid intelligence, and personality. Stepwise regression analyses revealed that online idiom comprehension was associated with the participants' working memory, inhibitory control and crystallized verbal intelligence, an association modulated by idiom type. Also personality-related variables (State Anxiety and Openness to Experience) were associated with idiom comprehension, although in marginally significant ways. These results contribute to the renewed interest on how individual variability modulates language comprehension, and for the first time document contributions of individual variability on lexicalized, high frequency multi-word expressions as idioms adding new knowledge to the existing evidence on metaphor and sarcasm.

Categorization Working Memory Span Task: Validation study of two Brazilian alternate versions

BACKGROUND

The Categorization Working Memory Span Task (CWMS task) is a complex working memory (WM) span test that has been used previously to assess age and individual differences in WM as well as the relationship between WM and complex aspects of cognition such as listening comprehension. Two alternate versions of the task have been developed to be used as outcome variables in WM training protocol, which mirrors the task involved in the CWMS task.

OBJECTIVES

(1) To translate and adapt the CWMS task for Brazilian Portuguese; (2) to test the equivalence of its 2 alternate versions; (3) to examine temporal stability; (4) to examine the influence of age and schooling on CWMS task; (5) to establish its relationship with other tests of WM.

METHODS

Eighty-one older adults completed version A, and 86 completed version B of the CWMS task. After 6 months, a subsample (n = 85) completed the same version of the task.

RESULTS

Versions A and B of the task generated comparable scores. Both versions had adequate temporal stability, which was higher for the CWMS total recall, which is the classical variable in this task to represent WM performance, when compared to the other variables generated by the test. The CWMS task variables were moderately correlated with schooling and other cognitive tests (Mini Mental State Examination, Letter-Number Sequencing, Spatial Span Backward, Digit Span Forward).

CONCLUSIONS

The 2 versions of the CWMS task were equivalent and stable temporally. The task was influenced by schooling and global cognition.

Inhibition, Updating Working Memory, and Shifting Predict Reading Disability Symptoms in a Hybrid Model: Project KIDS

Recent achievement research suggests that executive function (EF), a set of regulatory processes that control both thought and action necessary for goal-directed behavior, is related to typical and atypical reading performance. This project examines the relation of EF, as measured by its components, Inhibition, Updating Working Memory, and Shifting, with a hybrid model of reading disability (RD). Our sample included 420 children who participated in a broader intervention project when they were in KG-third grade (age M = 6.63 years, SD = 1.04 years, range = 4.79-10.40 years). At the time their EF was assessed, using a parent-report Behavior Rating Inventory of Executive Function (BRIEF), they had a mean age of 13.21 years (SD = 1.54 years; range = 10.47-16.63 years). The hybrid model of RD was operationalized as a composite consisting of four symptoms, and set so that any child could have any one, any two, any three, any four, or none of the symptoms included in the hybrid model. The four symptoms include low word reading achievement, unexpected low word reading achievement, poorer reading comprehension compared to listening comprehension, and dual-discrepancy response-to-intervention, requiring both low achievement and low growth in word reading. The results of our multilevel ordinal logistic regression analyses showed a significant relation between all three components of EF (Inhibition, Updating Working Memory, and Shifting) and the hybrid model of RD, and that the strength of EF's predictive power for RD classification was the highest when RD was modeled as having at least one or more symptoms. Importantly, the chances of being classified as having RD increased as EF performance worsened and decreased as EF performance improved. The question of whether any one EF component would emerge as a superior predictor was also examined and results showed that Inhibition, Updating Working Memory, and Shifting were equally valuable as predictors of the hybrid model of RD. In total, all EF components were significant and equally effective predictors of RD when RD was operationalized using the hybrid model.

Examining the role of rehearsal in old-old adults' working memory

We investigated the role of rehearsal in verbal working memory (WM) and whether WM capacity can be improved by a rehearsal instruction in very old age. In two experiments, we tested a total of 78 old-old adults (75 years and above) in one experimental session consisting of three assessment phases. First, participants worked on three different WM span tasks to assess their baseline performance. In the next phase, half of the participants received a rehearsal instruction to practice on two of the WM tasks, whereas the other half received no strategy instruction (Experiment 1) or worked on a filler task (Experiment 2). In the final phase, participants again worked on the three WM tasks. In Experiment 1, we found significant improvements for the WM tasks over time in both groups. However, we could not find a specific improvement for the rehearsal instruction due to a high spontaneous strategy use in the control group. When minimizing spontaneous strategy use in Experiment 2 by changing the task material, we found larger improvements in the instruction compared to the control group. However, we still found substantial spontaneous strategy use in the control group. The results indicate that rehearsal, as an essential component of verbal WM, is still intact and efficient in old-old adults. Furthermore, the spontaneous strategy use indicates that old-olds use their existing skills to cope with increasing WM demands. Finally, old-old adults benefited from an explicit rehearsal instruction showing potentials to boost WM capacity in this age group.

The Role of Interference Control in Working Memory: A Study with Children at Risk of Adhd

The study aimed to test whether the impairment in a working memory task observed in children at risk of ADHD was due to a lack of control of interfering information being processed whilst carrying out the memory task. Two groups of children at risk of ADHD with or without a learning disability (reading impairment) were compared to a control group in a working memory task. Activation of irrelevant items was tested with a lexical decision task presented immediately after the final recall in about half of the trials. Results showed a poor working memory performance in children at risk of ADHD and reading disability associated with a larger activation of irrelevant information than that of control children. Results indicated that the to-be-excluded and interfering items are still highly accessible to working memory in children that fail the working memory task. The examination of working memory and interference control of children at risk of ADHD with a learning disability revealed a counterintuitive picture of children with poor working memory showing better recall/activation of processed information. This picture is consistent with a view of working memory related to an efficient inhibitory control that influences cognitive functioning.

What Happens to Information to be Suppressed in Working–Memory Tasks? Short and Long Term Effects

The study explored, from an individual differences point of view, what happens to information to be suppressed in a working–memory task at short and long term. In particular, it was examined whether control mechanisms of irrelevant information in working memory imply their complete elimination from working memory or just the modulation of their activation. To this end, we compared the fate of irrelevant information in groups of subjects with high and low reading comprehension (Experiments 1 and 2) and subjects with high and low working memory (Experiments 1, 2, 3, and 4). All the experiments presented a working–memory task devised by De Beni, Palladino, Pazzaglia, and Cornoldi (1998), which required participants to process lists of words, to tap when a word from a particular category was presented, and then to recall only the last items in each list. Results confirmed that participants with high reading comprehension also have higher working memory and make less intrusion errors due to irrelevant items that have to be processed but then discarded. Furthermore, it was found that participants with low working memory have slightly better implicit (Experiment 1) and explicit memory (Experiments 3 and 4) of highly activated irrelevant information. Nevertheless, in a long–term recognition test, participants with high and low reading comprehension/working memory presented a similar pattern of memory for different types of irrelevant information (Experiment 2), whereas in a short–term memory recognition test, low–span participants presented a facilitation effect in the time required for the recognition of highly activated irrelevant information (Experiment 4). It was concluded that efficient working–memory performance is related to the temporary reduction of activation of irrelevant information but does not imply its elimination from memory.

Old-Fashioned Responses in an Updating Memory Task

Errors in a running memory task are analysed. Participants were presented with a variable-length list of items and were asked to report the last four items. It has been proposed (Morris & Jones, 1990) that this task requires two mechanisms: the temporal storage of the target set by the articulatory loop and its updating by the central executive. Two implicit assumptions in this proposal are (a) the preservation of serial order, and (b) participants’ capacity to discard earlier items from the target subset as list presentation is running, and new items are appended. Order preservation within the updated target list and the inhibition of the outdated list items should imply a relatively higher rate of location errors for items from the medial positions of the target list and a lower rate of intrusion errors from the outdated and inhibited items from the pretarget positions. Contrary to these expectations, for both consonants (Experiment 1) and words (Experiment 2) we found recency effects and a relatively high rate of intrusions from the final pretarget positions, most of them from the very last. Similar effects were apparent with the embedded four-item lists for catch trials. These results are clearly at odds with the presumed updating by the central executive.

Auditory and cognitive performance in elderly musicians and nonmusicians

Musicians represent a model for examining brain and behavioral plasticity in terms of cognitive and auditory profile, but few studies have investigated whether elderly musicians have better auditory and cognitive abilities than nonmusicians. The aim of the present study was to examine whether being a professional musician attenuates the normal age-related changes in hearing and cognition. Elderly musicians still active in their profession were compared with nonmusicians on auditory performance (absolute threshold, frequency intensity, duration and spectral shape discrimination, gap and sinusoidal amplitude-modulation detection), and on simple (short-term memory) and more complex and higher-order (working memory [WM] and visuospatial abilities) cognitive tasks. The sample consisted of adults at least 65 years of age. The results showed that older musicians had similar absolute thresholds but better supra-threshold discrimination abilities than nonmusicians in four of the six auditory tasks administered. They also had a better WM performance, and stronger visuospatial abilities than nonmusicians. No differences were found between the two groups' short-term memory. Frequency discrimination and gap detection for the auditory measures, and WM complex span tasks and one of the visuospatial tasks for the cognitive ones proved to be very good classifiers of the musicians. These findings suggest that life-long music training may be associated with enhanced auditory and cognitive performance, including complex cognitive skills, in advanced age. However, whether this music training represents a protective factor or not needs further investigation.

Recovery of Working Memory Following Pediatric Traumatic Brain Injury: A Longitudinal Analysis

In a prospective longitudinal study, the trajectory of verbal and visual-spatial working memory (WM) development was examined 2-, 6-, 12-, and 24-months following complicated-mild to severe pediatric traumatic brain injury (TBI; n = 55) relative to an orthopedic injury comparison group (n = 47). Individual growth curve modeling revealed an interaction of age, severity, and time for verbal, but not visual-spatial WM. The youngest children with severe TBI had the lowest scores and slowest verbal WM growth. WM outcome is best understood in light of age at injury and TBI severity. Findings support the early vulnerability hypothesis and highlight the need for long-term follow-up.

How working memory relates to children's reading comprehension: the importance of domain-specificity in storage and processing

Working memory is considered a well-established predictor of individual variation in reading comprehension in children and adults. However, how storage and processing capacities of working memory in both the phonological and semantic domain relate to reading comprehension is still unclear. In the current study, we investigated the contribution of phonological and semantic storage, and phonological and semantic processing to reading comprehension in 123 Dutch children in fifth grade. We conducted regression and mediation analyses to find out to what extent variation in reading comprehension could be explained by storage and processing capacities in both the phonological and the semantic domain, while controlling for children's decoding and vocabulary. The analyses included tasks that reflect storage only, and working memory tasks that assess processing in addition to storage. Regression analysis including only storage tasks as predictor measures, revealed semantic storage to be a better predictor of reading comprehension than phonological storage. Adding phonological and semantic working memory tasks as additional predictors to the model showed that semantic working memory explained individual variation in reading comprehension over and above all other memory measures. Additional mediation analysis made it clear that semantic storage contributed indirectly to reading comprehension via semantic working memory, indicating that semantic storage tapped by working memory, in addition to processing capacities, explains individual variation in reading comprehension. It can thus be concluded that semantic storage plays a more important role in children's reading comprehension than previously thought.

Inhibición y actualización en comprensión de textos: una revisión

El presente trabajo describe un conjunto de investigaciones en las que se indagan las relaciones entre funciones ejecutivas y comprensión de textos. Se revisan específicamente de qué forma se asocian los procesos de actualización e inhibición con la construcción de un significado global del texto por parte del lector en un contexto determinado. Se seleccionaron investigaciones a través de las base de datos Redalyc, Scielo, Pepsic y Dialnet, bajos los descriptores “funciones ejecutivas” y “comprensión lectora”. El corpus de investigaciones revisado no afirma en todos los casos que la inhibición sea discriminante de la comprensión exitosa. La actualización, en cambio, parece ser un buen predictor de la comprensión lectora en todos los trabajos revisados. Se puntualiza que los instrumentos diversos con que se han indagado ambas funciones ejecutivas limitan la comparación de resultados. Se propone para futuros estudios, realizar evaluaciones con similares instrumentos que permitan arribar a resultados comparables que sean la base para la evaluación y la intervención en comprensión de textos.

Control of information in working memory: Encoding and removal of distractors in the complex-span paradigm

The article reports four experiments with complex-span tasks in which encoding of memory items alternates with processing of distractors. The experiments test two assumptions of a computational model of complex span, SOB-CS: (1) distractor processing impairs memory because distractors are encoded into working memory, thereby interfering with memoranda; and (2) free time following distractors is used to remove them from working memory by unbinding their representations from list context. Experiment 1 shows that distractors are erroneously chosen for recall more often than not-presented stimuli, demonstrating that distractors are encoded into memory. Distractor intrusions declined with longer free time, as predicted by distractor removal. Experiment 2 shows these effects even when distractors precede the memory list, ruling out an account based on selective rehearsal of memoranda during free time. Experiments 3 and 4 test the notion that distractors decay over time. Both experiments show that, contrary to the notion of distractor decay, the chance of a distractor intruding at test does not decline with increasing time since encoding of that distractor. Experiment 4 provides additional evidence against the prediction from distractor decay that distractor intrusions decline over an unfilled retention interval. Taken together, the results support SOB-CS and rule out alternative explanations. Data and simulation code are available on Open Science Framework: osf.io/3ewh7.

Distracted While Reading? Changing to a Hard-to-Read Font Shields against the Effects of Environmental Noise and Speech on Text Memory

The purpose of this study was to investigate the distractive effects of background speech, aircraft noise and road traffic noise on text memory and particularly to examine if displaying the texts in a hard-to-read font can shield against the detrimental effects of these types of background sounds. This issue was addressed in an experiment where 56 students read shorter texts about different classes of fictitious creatures (i.e., animals, fishes, birds, and dinosaurs) against a background of the aforementioned background sounds respectively and silence. For half of the participants the texts were displayed in an easy-to-read font (i.e., Times New Roman) and for the other half in a hard-to-read font (i.e., Haettenschweiler). The dependent measure was the proportion correct answers on the multiple-choice tests that followed each sound condition. Participants’ performance in the easy-to-read font condition was significantly impaired by all three background sound conditions compared to silence. In contrast, there were no effects of the three background sound conditions compared to silence in the hard-to-read font condition. These results suggest that an increase in task demand—by displaying the text in a hard-to-read font—shields against various types of distracting background sounds by promoting a more steadfast locus-of-attention and by reducing the processing of background sound.

Location negative priming effects in children with developmental dyslexia: An event-related potential study

As the reading process is inseparable from working memory, inhibition, and other higher cognitive processes, the deep cognitive processing defects that are associated with dyslexia may be due to defective distraction inhibition systems. In this study, we used event-related potential technology to explore the source of negative priming effects in children with developmental dyslexia and in a group of healthy children for comparison. We found that the changes in the average response times in the negative priming and control conditions were consistent across the two groups, while the negative priming effects differed significantly between the groups. The magnitude of the negative priming effect was significantly different between the two groups, with the magnitude being significantly higher in the control group than it was in the developmental dyslexia group. These results indicate that there are deficits in distraction inhibition in children with developmental dyslexia. In terms of the time course of processing, inhibition deficits in the dyslexia group appeared during early-stage cognition selection and lasted through the response selection phase. Regarding the cerebral cortex locations, early-stage cognition selection was mainly located in the parietal region, while late-stage response selection was mainly located in the frontal and central regions. The results of our study may help further our understanding of the intrinsic causes of developmental dyslexia.

Children's comprehension skill and the understanding of nominal metaphors

According to Levorato and Cacciari's global elaboration model, understanding figurative language is explained by the same processes and background knowledge that are required for literal language. In this study, we investigated the relation between children's comprehension skill and the ability to understand referential nominal metaphors. Two groups of poor versus good comprehenders (8- to 10-year-olds) matched for word reading and vocabulary skills were invited to identify the referent of nouns used metaphorically or literally in short texts. Compared with good comprehenders, performance of poor comprehenders showed a substantial decrease in the metaphoric condition. Moreover, their performance was strongly affected by the degree of semantic incongruence between the terms of the nominal metaphor. These findings are discussed in relation to several factors, in particular the ability to use contextual information and semantic processing.

Subtypes and comorbidity in mathematical learning disabilities: Multidimensional study of verbal and visual memory processes is key to understanding

A large body of research suggests that mathematical learning disability (MLD) is related to working memory impairment. Here, I organize part of this literature through a meta-analysis of 36 studies with 665 MLD and 1049 control participants. I demonstrate that one subtype of MLD is associated with reading problems and weak verbal short-term and working memory. Another subtype of MLD does not have associated reading problems and is linked to weak visuospatial short-term and working memory. In order to better understand MLD we need to precisely define potentially modality-specific memory subprocesses and supporting executive functions, relevant for mathematical learning. This can be achieved by taking a multidimensional parametric approach systematically probing an extended network of cognitive functions. Rather than creating arbitrary subgroups and/or focus on a single factor, highly powered studies need to position individuals in a multidimensional parametric space. This will allow us to understand the multidimensional structure of cognitive functions and their relationship to mathematical performance.

Time-based prospective memory difficulties in children with ADHD and the role of time perception and working memory

Time-based prospective memory (PM) is the ability to remember to perform an intended action at a given time in the future. It is a competence that is crucial for effective performance in everyday life and may be one of the main causes of problems for individuals who have difficulty in planning and organizing their life, such as children with attention deficit/hyperactivity disorder (ADHD). This study systematically examines different aspects of time-based PM performance in a task that involves taking an action at a given future time in a group of 23 children with ADHD who were compared with a matched group of typically-developing (TD) children. The children were asked to watch a cartoon and then answer a questionnaire about its content (ongoing task). They were also asked to press a key every 2 minutes while watching the cartoon (PM task). The relationships of time perception and verbal working memory with PM performance were examined by administering appropriate tasks. The results showed that the children with ADHD were less accurate than the TD children in the PM task and exhibited less strategic time-monitoring behavior. Time perception was found to predict PM accuracy, whereas working memory was mainly involved in time-monitoring behavior, but this applied more to the TD group than to the ADHD group, suggesting that children with ADHD are less able to use their cognitive resources when meeting a PM request.

Does processing speed mediate the effect of pediatric traumatic brain injury on working memory?

OBJECTIVE

Processing speed (PS) and working memory (WM), core abilities that support learning, are vulnerable to disruption following traumatic brain injury (TBI). Developmental increases in WM are related to age-related changes in PS. The purpose of this study was to investigate whether WM deficits in children with TBI are mediated by PS.

METHOD

The performance of children with complicated mild, moderate, and severe TBI (n = 77) was examined relative to an orthopedic injury (n = 30) and a healthy comparison group (n = 40) an average of 4 years after injury (range 8 months to 12 years). Coding was utilized as a measure of PS, while the WM measures included complex verbal and visual-spatial span tasks with parallel processing requirements. Mediation analysis examined whether TBI might have an indirect effect on WM through PS.

RESULTS

Children in the TBI group performed more poorly than the combined comparison groups on coding and visual-spatial WM. Verbal WM scores were lower in TBI and the healthy comparison relative to the orthopedic group. TBI severity group differences were found on coding, but not WM measures. The relation between coding and both the WM tasks was similar. Bootstrap regression analyses suggested that PS, as measured by coding, might partially mediate the effect of group performance on WM.

CONCLUSIONS

TBI disrupts core PS and WM abilities that scaffold more complex abilities. Importantly, slowed PS was associated with WM deficits commonly identified following pediatric TBI. Implications of our findings regarding the relation between PS and WM may suggest interventions for children and adolescents following TBI.

Mathematics Anxiety, Working Memory, and Mathematics Performance in Secondary-School Children

Mathematics anxiety (MA) has been defined as “a feeling of tension and anxiety that interferes with the manipulation of numbers and the solving of math problems in a wide variety of ordinary life and academic situations.” Previous studies have suggested that a notable proportion of children in primary and secondary school suffer from MA, which is negatively correlated with calculation skills. The processing efficiency and attentional control theories suggest that working memory (WM) also plays an important part in such anxious feelings. The present study aimed to analyze the academic achievement and cognitive profiles of students with high math anxiety (HMA) and low math anxiety (LMA). Specifically, 32 students with HMA and 34 with LMA matched for age, gender, generalized anxiety, and vocabulary attending sixth to eighth grades were selected from a larger sample. The two groups were tested on reading decoding, reading comprehension, mathematics achievement, and on verbal short-term memory and WM. Our findings showed that HMA students were weak in several measures of mathematics achievement, but not in reading and writing skills, and that students with HMA reported lower scores on short-term memory and WM performances (with associated difficulties in inhibiting irrelevant information) than children with LMA. In addition, a logistic regression showed that weaknesses in inhibitory control and fact retrieval were the strongest variables for classifying children as having HMA or LMA.

What component of executive functions contributes to normal and impaired reading comprehension in young adults?

The purpose of this study was two-fold: (a) to examine what component of executive functions (EF) - planning and working memory - predicts reading comprehension in young adults (Study 1), and (b) to examine if less skilled comprehenders experience deficits in the EF components (Study 2). In Study 1, we assessed 178 university students (120 females; mean age=21.82 years) on planning (Planned Connections, Planned Codes, and Planned Patterns), working memory (Listening Span, Digit Span Backward, and Digit Memory), and reading comprehension (Nelson-Denny Reading Test). The results of structural equation modeling indicated that only planning was a significant predictor of reading comprehension. In Study 2, we assessed 30 university students with a specific reading comprehension deficit (19 females; mean age=23.01 years) and 30 controls (18 females; mean age=22.77 years) on planning (Planned Connections and Crack the Code) and working memory (Listening Span and Digit Span Backward). The results showed that less skilled comprehenders performed significantly poorer than controls only in planning. Taken together, the findings of both studies suggest that planning is the preeminent component of EF that is driving its relationship with reading comprehension in young adults.

Episodic future thinking: the role of working memory and inhibition on age-related differences

The ability to remember past events and imagine future events (episodic future thinking-EFT) has been shown to decline with aging. However, only few studies have analyzed the cognitive mechanisms involved in EFT in both young and older adults. The present study examined the role of working memory and inhibition on age-related differences between young and older adults in EFT, in response to short sentences reflecting common events, some of which were repeated in both conditions (past and future). Thirty-seven young and 36 older adults completed an adapted version of the autobiographical interview, in which sentences were presented. Results showed that processing resources explained a significant part of the variance in the amount of details; in particular, inhibition explained the amount of external details produced in the future condition. In addition, using sentences, the older group did not differ from the young adults in terms of the proportion of internal details recalled in the past condition, whereas they produced a lower proportion of internal details in the future condition. The effect of using structured material was reinforced by repeating some sentences in the past. Further, only older adults rated the remembered episodes as more emotionally salient and relevant than the imagined ones. Age-related differences between young and older adults in EFT appear to depend on the type of material used, on basic mechanisms of cognition, and are characterized by both quantitative and qualitative differences.

Executive Functions Differentially Contribute to Fourth Graders’ Mathematics, Reading, and Spelling Skills

Executive functions (EFs; working memory [WM], inhibition, and shifting) are widely known to play a critical role in school achievement. Among these EFs, WM appears to be implicated in numeracy and literacy. The contribution of inhibition and shifting to school achievement is less clear. Given the existing divergences in the literature and the importance of the interindividual differences in these domains, it seems important to assess EFs and scholastic skills in the same elementary school children. However, studies providing such an assessment are scarce. We explored whether EFs differentially contribute to mathematics, reading, and spelling skills in fourth-grade children (N = 71). The results revealed that (a) WM and inhibition accounted for unique variance in mathematics skills, (b) WM and shifting accounted for unique variance in reading skills, and (c) only shifting accounted for unique variance in spelling skills. The implications of these findings for children and teachers are discussed.

[Formula: see text]Working memory outcomes following traumatic brain injury in children: A systematic review with meta-analysis

The aim of this review is to systematically examine the literature concerning multicomponent working memory (WM)-comprising a central executive (CE), two storage components (phonological loop, PL and visuo-spatial sketchpad, VSSP), and episodic buffer (EB)-in pediatric traumatic brain injury (TBI). Electronic searches were conducted of MEDLINE, PsychINFO and EMBASE up to October 2014 with the inclusion criteria of children and adolescents with TBI, and quantitative methods to assess at least one component of WM. Meta-analytic procedures calculated pooled effect sizes for WM outcomes. Of the studies examined, 27 met the inclusion criteria. Children with TBI exhibited deficits in the CE and PL, but not in the VSSP, and no study could be found which examined the EB. Qualitative analysis found that greater TBI severity was associated with poorer CE functioning in five out of nine studies. Differences in patterns of brain activation were evident in four out of five fMRI studies that examined WM in TBI children and controls. Deficits in CE were associated with poorer mathematical skills in the only study that examined relations between WM and academic deficits. Notwithstanding the heterogeneity of the studies reviewed, TBI places children at risk of WM deficits. Moreover, this meta-analysis suggests that various components of WM have differential vulnerability to pediatric TBI, with significant deficits found in the CE and PL, but not in the VSSP (although the VSSP has rarely been examined to date). Future studies should be theoretically driven, employ tasks assessing all components of the WM model and examine the functional ramifications (including academic outcomes) of WM deficits in this population.

University Students With Poor Reading Comprehension: The Hidden Cognitive Processing Deficit

The present study aimed to examine the nature of the working memory and general cognitive ability deficits experienced by university students with a specific reading comprehension deficit. A total of 32 university students with poor reading comprehension but average word-reading skills and 60 age-matched controls with no comprehension difficulties participated in the study. The participants were assessed on three verbal working memory tasks that varied in terms of their processing demands and on the Das-Naglieri Cognitive Assessment System, which was used to operationalize intelligence. The results indicated first that the differences between poor and skilled comprehenders on working memory were amplified as the processing demands of the tasks increased. In addition, although poor comprehenders as a group had average intelligence, they experienced significant difficulties in simultaneous and successive processing. Considering that working memory and general cognitive ability are highly correlated processes, these findings suggest that the observed differences between poor and skilled comprehenders are likely a result of a deficient information processing system.

Working memory affects false memory production for emotional events

Whereas a link between working memory (WM) and memory distortions has been demonstrated, its influence on emotional false memories is unclear. In two experiments, a verbal WM task and a false memory paradigm for negative, positive or neutral events were employed. In Experiment 1, we investigated individual differences in verbal WM and found that the interaction between valence and WM predicted false recognition, with negative and positive material protecting high WM individuals against false remembering; the beneficial effect of negative material disappeared in low WM participants. In Experiment 2, we lowered the WM capacity of half of the participants with a double task request, which led to an overall increase in false memories; furthermore, consistent with Experiment 1, the increase in negative false memories was larger than that of neutral or positive ones. It is concluded that WM plays a critical role in determining false memory production, specifically influencing the processing of negative material.

Time and interference: Effects on working memory

This study tested predictions from the time-based resource-sharing (TBRS) model with a classical verbal working memory (WM) task, where target and non-target information interfere strongly with each other. Different predictions can be formulated according to the dominant perspectives (TBRS and interference hypothesis) on the role of inhibitory control in WM task performance. Here, we aimed to trace the activation of irrelevant information, examining priming effects in a lexical decision task immediately following WM recall. Results indicate the roles of both time and interference constraints in determining task performance. In particular, the role of time available seemed crucial at the highest WM loads (i.e., 3 and 4 memoranda). These were also associated with a higher activation of no-longer-relevant information but, in this case, independently from time available for processing.