Cognitive Working Memory Training (CWMT) in adolescents suffering from Attention-Deficit/Hyperactivity Disorder (ADHD): A controlled trial taking into account concomitant medication effects

Treating Executive Function in Youth With Attention Deficit Hyperactivity Disorder: A Review of Pharmacological and Non-Pharmacological Interventions

INTRODUCTION

Executive function (EF) deficits are common in youth with ADHD and pose significant functional impairments. The extent and effect of interventions addressing EF in youth with ADHD remain unclear.

METHODS

We conducted a systematic literature review using PRISMA guidelines. Included studies were randomized controlled trials of interventions to treat EF in youth with ADHD.

RESULTS

Our search returned 136 studies representing 11,443 study participants. We identified six intervention categories: nonstimulant pharmacological (N = 3,576 participants), neurological (N = 1,935), psychological (N = 2,387), digital (N = 2,416), physiological (N = 680), and combination (N = 366). The bulk of the evidence supported pharmacological interventions as most effective in mitigating EF, followed by psychological and digital interventions.

CONCLUSION

A breadth of treatments exists for EF in youth with ADHD. Pharmacological, psychotherapeutic, and digital interventions had the most favorable, replicable outcomes. A lack of outcome standardization across studies limited treatment comparison. More data on the persistence of intervention effects are necessary.

Effectiveness of executive functioning training among heterogeneous adolescent samples: A systematic review

The aim of the present systematic review was to discuss the reported efficacy of executive functioning training techniques among adolescents. A systematic review of the literature was conducted to retrieve and consolidate findings from articles evaluating executive functioning training techniques among adolescents. A total of 26 articles were located that examined the role of executive functioning training techniques among adolescents (age 10-19 years). Articles retrieved enabled comparison across psychiatric and medical diagnoses including attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), as well as adolescents with physical health concerns. Results revealed that among typically developing adolescents, executive functioning training was non-significant or yielded small effect size improvements in executive functioning as measured by behavioral and neuroimaging tasks among 62.5% of studies reviewed. In contrast, in those with medical conditions, ASD, ADHD, and conduct disorder, all but two studies reviewed yielded a medium to large effect size, supporting the effectiveness of EF training. Future research is needed to identify the long-term efficacy of these treatments, as well as their generalizability to real-world conditions.

Efficacy of non-pharmacological interventions on executive functions in children and adolescents with ADHD: A systematic review and meta-analysis

OBJECTIVE

Although front-line doctors recommend medications, this kind of treatment has limited efficacy in improving executive functions (EFs) in children and adolescents with attention-deficit/hyperactivity disorder (ADHD). This study explored the effects of non-pharmacological intervention on EFs in children and adolescents with ADHD.

METHODS

In accordance with the Preferred Reporting Items for Systematic Review and Meta-analyses guidelines, we searched seven electronic databases: APA PsycINFO, CINAHL Complete, EMBASE, ERIC, Medline, Pubmed, and Web of Science, from inception to March 2022. Two authors independently screened studies for eligibility, extracted data, and assessed bias risk using the Physiotherapy Evidence Database scale. Our analyses included randomized controlled trials and non-randomized comparison studies of non-pharmacological interventions and assessed EFs through neurocognitive tasks in children and adolescents between 5 and 18 years.

RESULTS

Sixty-seven studies with 3147 participants met the inclusion criteria. The final meta-analysis included 74 independent interventions categorized into six categories: cognitive training, EF-specific curriculum, game-based training, mindfulness practice, neurofeedback training, and physical exercise. Overall, non-pharmacological interventions (combined) produced significant moderate to large effects on overall EFs in children and adolescents with ADHD (g=0.673). Physical exercise had a large positive effect on domain-specific EFs, including inhibitory control (g=0.900) and cognitive flexibility (g=1.377). Cognitive training had a large training effect on working memory (g=0.907), and an EF-specific curriculum had a small to moderate beneficial effect on planning performance (g=0.532).

CONCLUSION

Non-pharmacological interventions, particularly physical exercise, cognitive training, and an EF-specific curriculum, appear to have beneficial effects on EFs in children and adolescents with ADHD.

SLD with and without ADHD: Comparison of cognitive profiles

A quarter of children with Specific Learning Disorder (SLD) have a comorbid attention deficit hyperactivity disorder (ADHD), which impacts the testing of intelligence. ADHD is therefore treated before proceeding with the assessment of intelligence. It is expected that the treatment of ADHD will mitigate its effects on intelligence testing. Though this is frequently done in clinical practice, we could not find any study comparing IQ profiles of children having SLD with and without ADHD after treating ADHD to look for any changes between them. Therefore, we planned this study to compare the cognitive profiles of children having SLD with and without ADHD and describe any difference in their profiles. It was a retrospective cross-sectional study. We compared 695 children having SLD with treated ADHD to 721 children having SLD without ADHD on their WISC III profiles. We found that children having SLD with treated ADHD scored significantly lower on Digit Span and Coding. We suggest routine use of Cognitive Working Memory Training, peer tutoring, and task modifications in children having SLD with ADHD along with medicines and remedial education for better outcomes.

Meta-analysis of the efficacy of digital therapies in children with attention-deficit hyperactivity disorder

Background

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that commonly occurs in childhood. The aim of this meta-analysis was to summarize the available evidence for the efficacy of digital therapeutics in children and adolescents with ADHD.

Methods

We searched the MEDLINE, EMBASE, Cochrane Library (Cochrane Database of Systematic Reviews), and Web of Science (science and social science citation index) databases for relevant studies and used Stata 15.0 software to carry out the meta-analysis.

Results

A total of 31 studies involving 2169 participants (1665 boys and 504 girls) aged 4-17 years old were included in the final analysis. The meta-analysis results showed that digital interventions improved the symptoms of inattention with an effect value of -0.20 (95% confidence interval [CI] -0.36, -0.04) and decreased the continuous performance task (CPT) reaction time (effect, -0.40, 95% CI -0.73, -0.07) in ADHD patients. The score for impulsive hyperactivity was slightly decreased (effect, -0.07, 95% CI -0.23, 0.09). Moreover, executive function was improved (effect, 0.71, 95% CI 0.37, 1.04). The capability of working memory appeared to be increased (effect, 0.48, 95% CI 0.21, 0.76) between the two groups. Visual appraisal of the sensitivity analysis suggested the absence of heterogeneity, and no obvious publication bias was detected.

Discussion

Based on the existing literature evidence, we conclude that digital therapy can be a promising therapeutic strategy for ADHD patients.

Combined effect of transcutaneous auricular vagus nerve stimulation and 0.1 Hz slow-paced breathing on working memory

Background

Previous research has found that transcutaneous auricular vagus nerve stimulation (taVNS) can improve working memory (WM) performance. It has also been shown that 0.1 Hz slow-paced breathing (SPB, i.e., breathing at a rate of approximately 6 breaths/min) can significantly influence physical state and cognitive function via changes in autonomic afferent activity. In the present study, we investigated the synergistic effects of taVNS and SPB on WM performance.

Methods

A total of 96 healthy people participated in this within-subjects experiment involving four conditions, namely taVNS, SPB, combined taVNS with SPB (taVNS + SPB), and sham. Each participant underwent each intervention for 30 min and WM was compared pre- and post-intervention using the spatial and digit n-back tasks in a random order four times. Permutation-based analysis of variance was used to assess the interaction between time and intervention.

Results

For the spatial 3-back task, a significant interaction between time and intervention was found for the accuracy rate of matching trials (mACC, p = 0.03). Post hoc analysis suggested that both taVNS and taVNS + SPB improved WM performance, however, no significant difference was found in the SPB or sham groups.

Conclusion

This study has replicated the effects of taVNS on WM performance reported in previous studies. However, the synergistic effects of combined taVNS and SPB warrant further research.

The effect of comprehensive working memory training on executive functions and behavioral symptoms in children with attention deficit-hyperactivity disorder (ADHD)

This study aimed to evaluate the effect of working memory training on executive functions and behavioral symptoms in children with ADHD. Thirty children with ADHD were randomly assigned to active control or Active Memory Intervention (AMIN) group. Executive functions and rating scales were used for assessment in three baseline, post-intervention, and 1-month follow-up sessions. The results show AMIN improves working memory and inhibitory control as well as ameliorates ADHD symptoms at home and school. Working memory training is beneficial and transferable intervention in children with ADHD.

Artificial Cognitive Systems Applied in Executive Function Stimulation and Rehabilitation Programs: A Systematic Review

This article presents a systematic review of studies on cognitive training programs based on artificial cognitive systems and digital technologies and their effect on executive functions. The aim has been to identify which populations have been studied, the characteristics of the implemented programs, the types of implemented cognitive systems and digital technologies, the evaluated executive functions, and the key findings of these studies. The review has been carried out following the PRISMA protocol; five databases have been selected from which 1889 records were extracted. The articles were filtered following established criteria, to give a final selection of 264 articles that have been used for the purposes of this study in the analysis phase. The findings showed that the most studied populations were school-age children and the elderly. The most studied executive functions were working memory and attentional processes, followed by inhibitory control and processing speed. Many programs were commercial, customizable, gamified, and based on classic tasks. Some more recent initiatives have begun to incorporate user-machine interfaces, robotics, and virtual reality, although studies on their effects remain scarce. The studies recognize multiple benefits of computerized neuropsychological stimulation and rehabilitation programs for executive functions in different age groups, but there is a lack of studies in specific population sectors and with more rigorous research designs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13369-022-07292-5.

Hospital-Based Modified Cogmed Working Memory Training for Youth With ADHD

OBJECTIVE

This study evaluated a modified working memory training program, Cogmed, for ADHD youth.

METHOD

Forty youth were randomized to modified Cogmed training (MCT) or treatment as usual (CON). MCT was delivered in an outpatient mental health clinic in 3 weekly 35-minute sessions with a dedicated coach for 10 weeks. Participants completed assessments at baseline, after the intervention, and again 3 months later.

RESULTS

After controlling for baseline, groups were comparable on working memory, academics, and ADHD symptoms. The MCT group was rated by parents and teachers as having fewer executive function challenges and youth endorsed better self-concept compared with the CON group.

CONCLUSIONS

MCT was associated with some improvement, which could not be attributed to increased working memory capacity and may reflect other facets of the program. Results question the usefulness of Cogmed but highlight considerations for optimizing adherence, engagement, and the therapeutic alliance in interventions for ADHD youth.

Can Neurocognitive Outcomes Assist Measurement-Based Care for Children with Attention-Deficit/Hyperactivity Disorder? A Systematic Review and Meta-Analyses of the Relationships Among the Changes in Neurocognitive Functions and Clinical Outcomes of Attention-Deficit/Hyperactivity Disorder in Pharmacological and Cognitive Training Interventions

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental conditions among school-age children. Early intervention and ongoing evaluation of treatment effectiveness are essential to minimize the life-long negative impact of ADHD. Neurocognitive functions have been reported to improve with pharmacological and cognitive training interventions for children with ADHD. We evaluated the value of measuring change in neurocognitive functions following ADHD interventions as a treatment outcome. We systematically reviewed randomized control trials of two distinctive types of ADHD interventions-pharmacological treatments and cognitive training-and summarized the changes in neurocognitive and clinical outcomes using a series of meta-analyses. Both pharmacological and cognitive training interventions showed positive effects on some aspects of neurocognitive functions. However, there were no significant correlations between changes in neurocognitive function (e.g., inhibition) and changes in ADHD behavioral symptoms (e.g., impulsive behavior). Although the associations between changes in neurocognitive function and clinical outcomes are not well studied, based on current findings, it is not suitable to use change in neurocognitive outcomes as a proxy for change in ADHD clinical symptom-based outcomes. There is, however, notable value in monitoring changes in neurocognitive function associated with ADHD interventions to achieve the following aims: (1) understanding full treatment effect on children with ADHD, (2) identifying ancillary indicators of subclinical changes, and (3) provision of objective and less biased measures of treatment effects. These findings are important evidence that changes in neurocognitive function could be a co-occurring objective indication that parallels the clinical effects of ADHD treatments.

Which Factor Is More Relevant to the Effectiveness of the Cognitive Intervention? A Meta-Analysis of Randomized Controlled Trials of Cognitive Training on Symptoms and Executive Function Behaviors of Children With Attention Deficit Hyperactivity Disorder

Objective: Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by developmentally inappropriate inattention, hyperactivity, and impulsivity. Multiple cognitive training appeared to be more effective than working memory training, but the evidence remains insufficient, particularly for the subgroup symptoms and executive function behaviors at home. Further analysis of the impact of factors on the effectiveness would facilitate the development of cognitive training.

Methods: We searched PubMed, Cochrane Library, Psyche, Embase, Chinese Biomedical Literature Database, CNKI, and Weifang Database, and included randomized controlled trials (RCTs) of children with ADHD undergoing cognitive intervention. Metaanalysis and univariate metaregression were performed by STATE. The risk of bias was assessed with the Cochrane risk of bias tool 2.0 by the two investigators separately. This study was registered with INPLASY, number INPLASY202140065.

Results: We included 17 RCTs in the systematic review, with a combined 1,075 participants. For metaanalyses of both subgroups of ADHD symptoms and the executive function behaviors, the test of published bias failed to reach the p < 0.05 level. When all of the training are considered together, cognitive training can improve the presentation of inattention symptoms [SMD = −0.390, 95%CI (−0.675, −0.104)] and executive function behaviors (SMD = −0.319, 95%CI (−0.527, −0.111)]. In the subgroup analysis, the effects of working memory training on both presentations were not statistically significant. In contrast, the multiple cognitive training had significant effects on the presentation of inattention symptoms [SMD = −0.507, 95% CI (−0.722, −0.292)], hyperactivity/impulsivity [SMD = −0.305, 95% CI (−0.518, −0.09)], and the executive function behaviors [SMD = −0.499, 95%CI (−0.707, −0.290)]. In addition, metaregression analysis showed that only training frequency did significantly impact the symptoms of ADHD and the executive function behaviors.

Conclusion: This study showed that improvements in symptoms and executive function behaviors were related to the domains of cognitive intervention. The findings suggest that multiple domains of cognitive training and moderate training frequency may have wider clinical benefits. All the above results highlight further research in refining the executive functions of children with ADHD and developing individually tailored cognitive intervention on homes based for children with vulnerable executive functions.

Systematic Review Registration: [http://inplasy.com/], [INPLASY202140065].

Assessing the feasibility of a classroom-based visual attention training program targeting academics for students with extremely low IQ

BACKGROUND

This feasibility study investigated the viability of implementing a cognitive-based training program (NeuroTracker) and assessing its potential effects on academic performance for adolescents with extremely low IQ.

METHODS

Twenty-six adolescents aged between 11 and 16 years with a Wechsler-based IQs in the extremely low range (MIQ = 56.00, SDIQ = 13.89) completed 15 training sessions on either the NeuroTracker or an active control task; math and reading performance were assessed using clinically validated instruments before and after training. Recruitment and retention rates, adherence, and properties of the academic measures were assessed.

RESULTS

All recruited participants completed 15 training sessions within a 6-week period. Eighty-three percent of participants meeting initial inclusion criteria completed all stages of the study from baseline to post-intervention assessments. Some limitations of the academic measures were identified.

CONCLUSIONS

Results suggest that implementing NeuroTracker as a classroom-based intervention and using clinically validated outcome measures is feasible with this population.

Dual n-back working memory training evinces superior transfer effects compared to the method of loci

Working memory (WM) training is a prevalent intervention for multiple cognitive deficits, however, the transfer effects to other cognitive tasks from gains in WM induced by different training techniques still remains controversial. Therefore, the current study recruited three groups of young adults to investigate the memory training transference, with N-back group (NBG) (n = 50) training on dual n-back task, Memory Palace group (MPG) (n = 50) on method of loci, and a blank control group (BCG) (n = 48) receiving no training. Our results showed that both training groups separately improved WM capacity on respective trained task. For untrained tasks, both training groups enhanced performance on digit-span task, while on change detection task, significant improvement was only observed in NBG. In conclusion, while both techniques can be used as effective training methods to improve WM, the dual n-back task training method, perhaps has a more prominent transfer effect than that of method of loci.

Working memory training effects across the lifespan: Evidence from human and experimental animal studies

Working memory refers to a cognitive function that provides temporary storage and manipulation of the information necessary for complex cognitive tasks. Due to its central role in general cognition, several studies have investigated the possibility that training on working memory tasks could improve not only working memory function but also increase other cognitive abilities or modulate other behaviors. This possibility is still highly controversial, with prior studies providing contradictory findings. The lack of systematic approaches and methodological shortcomings complicates this debate even more. This review highlights the impact of working memory training at different ages on humans. Finally, it demonstrates several findings about the neural substrate of training in both humans and experimental animals, including non-human primates and rodents.

Effects and Moderators of Computer-Based Training on Children's Executive Functions: A Systematic Review and Meta-Analysis

Computer-based training has attracted increasing attention from researchers in recent years. Several studies have found that computer-based training resulted in improved executive functions (EFs) in adults. However, it remains controversial whether children can benefit from computer-based training and what moderator could influence the training effects. The focus of the present meta-analysis was to examine the effects of computer-based training on EFs in children: working memory, cognitive flexibility, and inhibitory control. A thorough search of published work yielded a sample of 36 studies with 216 effect sizes. The results indicated that computer-based training showed moderate training effects on improving EFs in children (g = 0.35, k = 36, p < 0.001), while training effects of working memory were significantly higher. Furthermore, we found near-transfer effects were marginally significantly higher than far-transfer effects. The standard training method was significantly more effective than training with game elements. In computer-based training, typically developing children had significantly better training effects than atypically developing children. Some additional factors, such as the number of training sessions and age, also modulated the training effects. In conclusion, the present study investigated the effects and moderators of computer-based training for children's EFs. The results provided evidence that computer-based training (especially standard training) may serve as an efficient way to improve EFs in children (especially typically developing individuals). We also discussed some directions for future computer-based training studies.

Early Attentional Modulation by Working Memory Training in Young Adult ADHD Patients during a Risky Decision-Making Task

Background: Working memory (WM) deficits and impaired decision making are among the characteristic symptoms of patients affected by attention deficit/hyperactivity disorder (ADHD). The inattention associated with the disorder is likely to be due to functional deficits of the neural networks inhibiting irrelevant sensory input. In the presence of unnecessary information, a good decisional process is impaired and ADHD patients tend to take risky decisions. This study is aimed to test the hypothesis that the level of difficulty of a WM training (WMT) is affecting the top-down modulation of the attentional processes in a probabilistic gambling task. Methods: Event-related potentials (ERP) triggered by the choice of the amount wagered in the gambling task were recorded, before and after WMT with a the dual n-back task, in young ADHD adults and matched controls. For each group of participants, randomly assigned individuals were requested to perform WMT with a fixed baseline level of difficulty. The remaining participants were trained with a performance-dependent adaptive n-level of difficulty. Results: We compared the ERP recordings before and after 20 days of WMT in each subgroup. The analysis was focused on the time windows with at least three recording sites showing differences before and after training, after Bonferroni correction ( p < 0.05 ). In ADHD, the P1 wave component was selectively affected at frontal sites and its shape was recovered close to controls' only after adaptive training. In controls, the strongest contrast was observed at parietal level with a left hemispheric dominance at latencies near 900 ms, more after baseline than after adaptive training. Conclusion: Partial restoration of early selective attentional processes in ADHD patients might occur after WMT with a high cognitive load. Modified frontal sites' activities might constitute a neural marker of this effect in a gambling task. In controls, conversely, an increase in late parietal negativity might rather be a marker of an increase in transfer effects to fluid intelligence.

Effects of working memory intervention on students with reading comprehension difficulties

ABSTRACT Purpose: to investigate the effectiveness of a working memory-based intervention proposal for reading comprehension. Methods: 43 children divided into two groups according to their performance in a reading comprehension test - G1: children with reading comprehension difficulty; G2: children with no difficulties. All the children were evaluated regarding reading, writing, sentence reading comprehension, and phonological working memory - PWM (repetition of pseudo-words and digits). After this evaluation, children from G1 participated in an intervention program (15 meetings) that stimulated the PWM. Following the intervention, all the children were reevaluated. The results were compared intra- and intergroup, and pertinent statistical tests were applied, by adopting the significance level lower than 0.05%. Results: after the intervention program, the children of G1 showed a significant improvement in all tests. In the intergroup analysis, at the time of evaluation, G1 was different from G2 in reading, writing and reading comprehension. In the reevaluation, G1 equaled G2 in reading and got closer to G2 in writing and reading comprehension. Conclusion: PWM training brought benefits to children with academic difficulties. Thus, these strategies could be used in the classroom, aiming to promote learning.