Effects of working memory training on neural correlates of Go/Nogo response control in adults with ADHD: A randomized controlled trial

Effects and feasibility of psychological interventions to reduce inattention symptoms in adults with ADHD: a systematic review

BACKGROUND

Adult ADHD is common, highly comorbid, and restricts daily functioning. However, only a minority of patients receive appropriate treatment.

AIMS

Primary objective: To identify psychological interventions that diminish inattention symptoms in adults with ADHD. Secondary objective: To evaluate feasibility aspects.

METHODS

A search in PubMed, Cochrane Library, PsycInfo, PSYNDEX, and Eric was conducted. Interventions were grouped in: ADHD coaching, neuro feedback, cognitive training, psychoeducation, and behavioral therapy. Inattention symptoms were evaluated using standardized mean differences. Study quality was rated with the Cochrane Risk of Bias tool. Feasibility was assessed by number and time of sessions, setting, and qualification of the provider.

RESULTS

A total of N = 2229 results were identified, 19 randomized controlled studies were included in the analysis. Behavioral therapy showed effects on inattention symptoms [SMD: 0.44-1.71] when compared to inactive controls. In terms of feasibility, longer interventions did not outperform shorter ones and individual sessions were not superior to group sessions. No effects were given for neuro feedback, cognitive training, and psychoeducation in comparison to controls.

CONCLUSION

For adults with ADHD behavioral therapy seems an effective intervention to reduce inattention symptoms. In terms of feasibility, brief interventions may be valuable for a primary care setting.

Computerized working memory training for adults with ADHD in a psychiatric outpatient context-a feasibility trial

This study investigated the feasibility (treatment completion, and acceptability) and preliminary effectiveness of computerized working memory (WM) training in a psychiatric outpatient context for adults with ADHD. Self-ratings, neuropsychological tests, and clinician's assessments were performed pre- and post-Cogmed WM training, as well as at the 2-month follow-up, which included 24 (age M = 36.75 SD = 8.37) participants. Of the 24 participants, 16 (66.67%) completed the 25 sessions within 7 weeks. Completers reported high treatment credibility, but a few spontaneously reported feeling stressed because of the time-consuming nature of the WM training (n = 4). Preliminary effectiveness analyses indicate fewer cognitive difficulties and increased neuropsychological performance in non-trained tests that remained stable at follow-up. Future development of WM training paradigms could investigate ways of making the perception of training experience less demanding regarding being time-consuming. The indication of preliminary effectiveness merits further randomized controlled studies in a clinical context.

Perspectives on heterogeneity-informed cognitive training for attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (AD/HD) is a heterogeneous neurodevelopmental condition, posing a severe threat to quality of life. Pharmacological therapies are the front-line treatment; however, their shortages encourage the development of alternative treatments for AD/HD. One promising method of developing alternative treatments is cognitive training (CT). A CT-based therapy was recently approved by the US Food and Drug Administration. However, due to heterogeneity in AD/HD, a CT protocol is unlikely to provide a one-size-fits-all solution for all patients with AD/HD. Therefore, this article highlights key aspects that need to be considered to further develop CT protocols for AD/HD, regarding training content, timing, suitability, and delivery mode. The perspectives presented here contribute to optimizing CT as an alternative option for treating AD/HD.

Tactile angle discriminability improvement: Contributions of working memory training and continuous attended sensory input

Perceptual learning is commonly assumed to enhance perception through continuous attended sensory input. However, learning is generalizable to performance in untrained stimuli and tasks. Although previous studies have observed a possible generalization effect across tasks as a result of working memory (WM) training, comparisons of the contributions of WM training and continuous attended sensory input to perceptual learning generalization are still rare. Therefore, we compared which factors contributed most to perceptual generalization and investigated which skills acquired during WM training led to tactile generalization across tasks. Here, a Braille-like dot pattern matching n-back WM task was used as the WM training task, with four workload levels (0, 1, 2, and 3-back levels). A tactile angle discrimination (TAD) task was used as a pre- and posttest to assess improvements in tactile perception. Between tests, four subject groups were randomly assigned to four different workload n-back tasks to consecutively complete three sessions of training. The results showed that tactile n-back WM training could enhance TAD performance, with the 3-back training group having the highest TAD threshold improvement rate. Furthermore, the rate of WM capacity improvement on the 3-back level across training sessions was correlated with the rate of TAD threshold improvement. These findings suggest that continuous attended sensory input and enhanced WM capacity can lead to improvements in TAD ability, and that greater improvements in WM capacity can predict greater improvements in TAD performance.

NEW & NOTEWORTHY Perceptual learning is not always specific to the trained task and stimuli. We demonstrate that both continuous attended sensory input and improved WM capacity can be used to enhance tactile angle discrimination (TAD) ability. Moreover, WM capacity improvement is important in generalizing the training effect to the TAD ability. These findings contribute to understanding the mechanism of perceptual learning generalization across tasks.

Electroencephalography complexity in resting and task states in adults with attention-deficit/hyperactivity disorder

Analysing EEG complexity could provide insight into neural connectivity underlying attention-deficit/hyperactivity disorder symptoms. EEG complexity was calculated through multiscale entropy and compared between adults with attention-deficit/hyperactivity disorder and their peers during resting and go/nogo task states. Multiscale entropy change from the resting state to the task state was also examined as an index of the brain’s ability to change from a resting to an active state. Thirty unmedicated adults with attention-deficit/hyperactivity disorder were compared with 30 match-paired healthy peers on the multiscale entropy in the resting and task states as well as their multiscale entropy change. Results showed differences in multiscale entropy between individuals with attention-deficit/hyperactivity disorder and their peers during the resting state as well as the task state. The multiscale entropy measured from the comparison group was larger than that from the attention-deficit/hyperactivity disorder group in the resting state, whereas the reverse pattern was found during the task state. Our most robust finding showed that the multiscale entropy change from individuals with attention-deficit/hyperactivity disorder was smaller than that from their peers, specifically at frontal sites. Interestingly, individuals without attention-deficit/hyperactivity disorder performed better with decreasing multiscale entropy changes, demonstrating higher accuracy, faster reaction time and less variability in their reaction times. These data suggest that multiscale entropy could not only provide insight into neural connectivity differences between adults with attention-deficit/hyperactivity disorder and their peers but also into their behavioural performance.

A preliminary randomized, controlled trial of executive function training for children with autism spectrum disorder

LAY ABSTRACT

Executive function, which is a set of thinking skills that includes stopping unwanted responses, being flexible, and remembering information needed to solve problems, is a challenge for many children on the autism spectrum. This study tested whether executive function could be improved with a computerized executive function training program under the guidance of a coach who reinforced the use of executive function skills. Seventy children with autism spectrum disorder from age 7 to 11 years of age participated in the study. They were randomly assigned to receive training or to a waiting group. The tests most likely to determine whether the training may be effective were chosen from a larger battery before the study started and included one task measuring brain responses, two measures of executive function in the lab, and a parent questionnaire. Changes in social functioning and repetitive behaviors were also explored. All children assigned to training completed the program and families generally reported the experience was positive. Brain responses of the training group changed following training, but not within the waiting group during a similar time period. Children who received training did not exhibit behavioral changes during the two the lab-based tasks. Parent report on questionnaires indicated that neither group showed a significant change in their broad use of executive function in other settings. Yet, children who received training were reported to have fewer restricted and repetitive behaviors following training. These initial findings suggest that short executive function training activities are feasible and may improve some functioning of school-aged children on the autism spectrum.

Objective assessment of impulse control disorder in patients with Parkinson's disease using a low-cost LEGO-like EEG headset: a feasibility study

Background

Patients with Parkinson’s disease (PD) can develop impulse control disorders (ICDs) while undergoing a pharmacological treatment for motor control dysfunctions with a dopamine agonist (DA). Conventional clinical interviews or questionnaires can be biased and may not accurately diagnose at the early stage. A wearable electroencephalogram (EEG)-sensing headset paired with an examination procedure can be a potential user-friendly method to explore ICD-related signatures that can detect its early signs and progression by reflecting brain activity.

Methods

A stereotypical Go/NoGo test that targets impulse inhibition was performed on 59 individuals, including healthy controls, patients with PD, and patients with PD diagnosed by ICDs. We conducted two Go/NoGo sessions before and after the DA-pharmacological treatment for the PD and ICD groups. A low-cost LEGO-like EEG headset was used to record concurrent EEG signals. Then, we used the event-related potential (ERP) analytical framework to explore ICD-related EEG abnormalities after DA treatment.

Results

After the DA treatment, only the ICD-diagnosed PD patients made more behavioral errors and tended to exhibit the deterioration for the NoGo N2 and P3 peak amplitudes at fronto-central electrodes in contrast to the HC and PD groups. Particularly, the extent of the diminished NoGo-N2 amplitude was prone to be modulated by the ICD scores at Fz with marginal statistical significance (r = − 0.34, p = 0.07).

Conclusions

The low-cost LEGO-like EEG headset successfully captured ERP waveforms and objectively assessed ICD in patients with PD undergoing DA treatment. This objective neuro-evidence could provide complementary information to conventional clinical scales used to diagnose ICD adverse effects.

Visuospatial Working Memory Capacity in the Brain After Working Memory Training in College Students With ADHD: A Randomized Controlled Trial

Objective: ADHD has been associated with persistent problems of working memory. This study investigated the efficacy of an intensive and adaptive computerized working memory treatment (CWMT) at behavioral and neural levels. Method: College students (n = 89; 40 females) with ADHD were randomized into a standard-length CWMT (45 min/session, 25 sessions, n = 29), shortened-length CWMT (15 min/session, 25 sessions, n = 32), and a waitlist group (n = 28). Both CWMT groups received treatment for 5 days a week for 5 weeks. Lab sessions before and after CWMT assessed electroencephalography (EEG) indicators of working memory, behavioral indicators of working memory performance, and ADHD symptomatology. Results: No evidence was found for neural or any other behavioral transfer effects of improvement for the CWMT treatment groups over the active control or waitlist group. Conclusion: Our study does not provide evidence for the benefits of CWMT at neural or behavioral levels.

Randomized Controlled Trial of Working Memory Intervention in Congenital Heart Disease

OBJECTIVES

To evaluate the efficacy of Cogmed Working Memory Training compared with the standard of care to improve executive function and social outcomes in adolescents with congenital heart disease (CHD) who underwent open-heart surgery in infancy and to identify factors associated with changes in outcomes following the intervention.

STUDY DESIGN

In a single-center, randomized controlled trial, adolescents (13-16 years) with CHD were randomly assigned to either Cogmed (home-based 45-minutes sessions for 5-8 weeks) or to a control group. The primary outcome was working memory. Secondary outcomes included inhibitory control and cognitive flexibility as well as parent-reported executive function, symptoms of attention deficit hyperactivity disorder, and social outcomes. All measures were assessed at baseline, post-treatment (1-3 weeks post-training) and at 3-month follow-up. Data were analyzed using an intention-to-treat approach.

RESULTS

Sixty adolescents with CHD participated (28 assigned to Cogmed). No improvement at the post-treatment or 3-month follow-up assessments was found for the primary outcome measure of working memory. Compared with the control group, participants assigned to the intervention demonstrated benefits in inhibitory control and attention at the 3-month follow-up (P = .02) and in parent-reported cognitive regulatory skills at post-treatment and 3-month follow-up (P = .02 and P = .04, respectively). Preterm birth, biventricular CHD, and history of attention deficit hyperactivity disorder diagnosis were associated with improved response to the intervention.

CONCLUSIONS

Cogmed intervention produced improvements in the self-regulatory control abilities of adolescents with CHD. The training did not enhance other areas of executive function or behavioral outcomes. Further studies are needed to evaluate the longer-term potential benefits to other domains.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02759263.

Brain Mapping Performance as an Occupational Therapy Assessment Aid in Attention Deficit Hyperactivity Disorder

IMPORTANCE

Brain mapping performance (BMP) may provide strong predictors to analyze primary functional outcomes and support occupational therapy with clients with attention deficit hyperactivity disorder (ADHD).

OBJECTIVE

To clarify the value of quantitative electroencephalography to indicate BMP in children with ADHD.

DESIGN

One-year cross-sectional study.

SETTING

Brain Computer Interface Laboratory, Mahidol University, Salaya, Nakhon Pathom, Thailand.

PARTICIPANTS

Thai school-age children with and without ADHD (N = 305).

OUTCOMES AND MEASURES

We used θ relative power in concordance with stepwise multiple regression analysis. Outcomes included measures of 12 brain locations that were compared between children with and without ADHD.

RESULTS

Significant differences were found between the groups, especially for Cz, T3, Fp1, Fz, F4, and F7. According to BMP, the group with ADHD had higher emotional awareness and language comprehension than the group without ADHD.

CONCLUSIONS AND RELEVANCE

Occupational therapy practitioners can use BMP as a valuable tool for setting occupational goals to help children with ADHD improve their social-emotional learning performance in school and in the community. BMP may provide an evaluation to support occupational therapy services for clients with ADHD. The result can be applied in clinical settings by quantitative electroencephalography training.

WHAT THIS ARTICLE ADDS

BMP can be used as a neuropsychological and behavioral assessment tool for setting SMART (specific, measurable, attainable, relevant, and time-oriented) goals for occupational therapy services for clients with ADHD.

Neurophysiological indices of the transfer of cognitive training gains to untrained tasks

Targeted training of working memory (WM) may improve performance and modulate brain function in untrained cognitive modalities. Demanding cognitive training protocols that do not target WM may also improve performance on untrained cognitive tests, but the delineation between transfer effects that are unique to WM training and effects that are shared among different cognitive training modalities has not been well-established. To address this, we examined the effects of twenty sessions of either WM training (visual n-back task with letter stimuli) or selective attention training (visual search task with letter array stimuli) on brain function during untrained WM and cognitive control tasks. Event-related potentials (ERPs) were obtained at baseline (pretest) and after the training period (posttest) for two untrained tasks - a Spatial 3-back task measuring spatial WM, and a Go/NoGo Flanker task measuring cognitive control. The n-back training group had more pronounced pretest-to-posttest performance improvements on the Spatial 3-back task compared to the search training group. N-back training was also associated with pretest-to-posttest enhancement of N1 amplitude and reduced N2 latency on trials of the task in which where there was a stimulus match, as well as enhancement of a late positive potential (550-750 msec post-stimulus) for all trials of the task. These ERP effects suggest that n-back training resulted in enhancement of attention to spatial locations, earlier onset of conflict monitoring processes, and changes in the engagement of neural activity during the retention interval, respectively. Both groups had faster reaction time on Go trials of the Go/NoGo Flanker task at posttest compared to pretest. Relatively subtle training-related effects were observed for N2 amplitude on this task, in line with the notion that training (particularly n-back training) was associated with improved conflict monitoring. Further, search training resulted in earlier onset of P2 and P3 latency at posttest compared to pretest. Taken together, the ERP findings for both tasks identify specific cognitive processes that are associated with transfer to untrained tasks after distinct forms of cognitive training.

Cognitive rehabilitation in children with attention deficit- hyperactivity disorder: Transferability to untrained cognitive domains and behavior

Transferability of cognitive rehabilitation is a crucial point for efficacy. The purpose of the present study is to determine the transfer effect of cognitive rehabilitation to the untrained cognitive domains and behavior in children with attention deficit- hyperactivity disorder (ADHD). Thirty children with ADHD randomly allocated into two intervention and control groups. The intervention group received cognitive rehabilitation in 12-15 sessions. Analyses indicated that the experimental group shows an improvement in the trained domain. The result found a lack of near transfer to selective attention and inhibitory control with a successful far transfer effect to the risky decision making and delay discounting. Furthermore, the transfer occurred to behavioral symptoms of the intervention group. Attention and working memory training decrease delay discounting and delay discounting. The near transfer is not a prerequisite of far transfer. Cognitive rehabilitation can transfer horizontally to other cognitive domains at the same level and vertically to behaviors in a top-down manner.

Neuropsychological classification based on brain mapping performance in Thai children with and without ADHD

This study investigated the cognitive strengths and weaknesses of Attention Deficit Hyperactivity Disorder (ADHD) patients by using quantitative electroencephalography (QEEG) to analyze brain mapping outcomes in relation to neuropsychological assessments. A total of 305 participants with and without ADHD were recruited. The theta relative power of QEEG was analyzed using stepwise multiple regression, and twelve scalp regions were compared between groups using independent t-tests. Increased power was found at the T5 scalp region in the ADHD group and at the F4 region in the non-ADHD group. Decreased power was found at the F7 region in the ADHD group and at the F3 region in the non-ADHD group. Six of the twelve brain locations had significantly higher theta relative power in the ADHD group than in the non-ADHD group. These brain mapping outcomes can be easily translated to neuropsychological functions, such as attention, executive function, memory, spatial ability, and language, to better understand or predict the potential behavior of ADHD patients.

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.

Is Computerized Working Memory Training Effective in Healthy Older Adults? Evidence from a Multi-Site, Randomized Controlled Trial

BACKGROUND

Developing effective interventions to attenuate age-related cognitive decline and prevent or delay the onset of dementia are major public health goals. Computerized cognitive training (CCT) has been marketed increasingly to older adults, but its efficacy remains unclear. Working memory (WM), a key determinant of higher order cognitive abilities, is susceptible to age-related decline and a relevant target for CCT in elders.

OBJECTIVE

To evaluate the efficacy of CCT focused on WM compared to an active control condition in healthy older adults.

METHODS

Eighty-two cognitively normal adults from two sites (USA and Sweden) were randomly assigned to Cogmed Adaptive or Non-Adaptive (active control) CCT groups. Training was performed in participants' homes, five days per week over five weeks. Changes in the performance of the Cogmed trained tasks, and in five neuropsychological tests (Trail Making Test Part A and Part B, Digit Symbol, Controlled Oral Word Association Test and Semantic Fluency) were used as outcome measures.

RESULTS

The groups were comparable at baseline. The Adaptive group showed robust gains in the trained tasks, and there was a time-by-group interaction for the Digit Symbol test, with significant improvement only after Adaptive training. In addition, the magnitude of the intervention effect was similar at both sites.

CONCLUSION

Home-based CCT Adaptive WM training appears more effective than Non-Adaptive training in older adults from different cultural backgrounds. We present evidence of improvement in trained tasks and on a demanding untrained task dependent upon WM and processing speed. The benefits over the active control group suggest that the Adaptive CCT gains were linked to providing a continuously challenging level of WM difficulty.

Effects of Integrated Brain, Body, and Social (IBBS) intervention on ERP measures of attentional control in children with ADHD

A primary goal of this study was to examine the impact of an Integrated Brain, Body, and Social (IBBS) intervention (multi-faceted treatment consisting of computerized cognitive training, physical exercise, and behavior management) on ERPs of attentional control (P3 & N2) in children with ADHD. The secondary goal was to test the differences between children with and without ADHD on ERP and Go/No-Go behavioral measures. A total of twenty-nine participants (M age = 7.14 years; 52% male; 41.4% white) recruited from the IBBS efficacy study comparing IBBS to Treatment-As-Usual (TAU) completed a Go/No-Go task before and after treatment as brain activity was recorded using EEG. Thirty-four matched healthy controls (HC) completed the same EEG procedures at a single time point. Following treatment, the Go P3 latency was significantly earlier for the IBBS group relative to the TAU group. No treatment effects were found on any behavioral measures. Prior to treatment, there was a significant difference between the ADHD group and HC group for the N2 difference wave. Children with ADHD also showed slower reaction times on behavioral measures. Although this pilot study did not reveal robust treatment effects, it suggests that IBBS may prevent the worsening of attentional systems in the brain and larger studies are needed for replication purposes.

Neural processing of working memory in adults with ADHD in a visuospatial change detection task with distractors

Individuals with Attention-Deficit Hyperactivity Disorder (ADHD) are often characterized by deficits in working memory (WM), which manifest in academic, professional, and mental health difficulties. To better understand the underlying mechanisms of these presumed WM deficits, we compared adults with ADHD to their peers on behavioral and neural indices of WM. We used a visuospatial change detection task with distractors which was designed to assess the brain’s ability to effectively filter out distractors from WM, in addition to testing for effects of WM load. Twenty-seven unmedicated adults with ADHD were compared to 27 matched peers on event-related potential (ERP) measures of WM, i.e., the contralateral delay activity (CDA). Despite severe impairments in everyday life functioning, findings showed no difference in deficits in behavioral tests of working memory for adults with ADHD compared to their peers. Interestingly, there were differences in neural activity between individuals with ADHD and their peers showing that the CDA of individuals with ADHD did not distinguish between high, distractor, and low memory load conditions. These data suggest, in the face of comparable behavioral performance, a difference in neural processing efficiency, wherein the brains of individuals with ADHD may not be as selective in the allocation of neural resources to perform a WM task.

Motor dysfunction as research domain across bipolar, obsessive-compulsive and neurodevelopmental disorders

Although genuine motor abnormalities (GMA) are frequently found in schizophrenia, they are also considered as an intrinsic feature of bipolar, obsessive-compulsive, and neurodevelopmental disorders with early onset such as autism, ADHD, and Tourette syndrome. Such transnosological observations strongly suggest a common neural pathophysiology. This systematic review highlights the evidence on GMA and their neuroanatomical substrates in bipolar, obsessive-compulsive, and neurodevelopmental disorders. The data lends support for a common pattern contributing to GMA expression in these diseases that seems to be related to cerebello-thalamo-cortical, fronto-parietal, and cortico-subcortical motor circuit dysfunction. The identified studies provide first evidence for a motor network dysfunction as a correlate of early neurodevelopmental deviance prior to clinical symptom expression. There are also first hints for a developmental risk factor model of these mental disorders. An in-depth analysis of motor networks and related patho-(physiological) mechanisms will not only help promoting Research Domain Criteria (RDoC) Motor System construct, but also facilitate the development of novel psychopharmacological models, as well as the identification of neurobiologically plausible target sites for non-invasive brain stimulation.

Computer-assisted rehabilitation of attention in pediatric multiple sclerosis and ADHD patients: a pilot trial

BACKGROUND

The treatment of cognitive deficits is challenging in pediatric onset multiple sclerosis (POMS) and in patients with attention deficit hyperactivity disorder (ADHD). We performed a pilot double-blind RCT to evaluate the efficacy of a home-based computerized-program for retraining attention in two cohorts of POMS and ADHD patients.

METHODS

POMS and ADHD patients failing in at least 2/4 attention tests on a neuropsychological battery were randomized to specific or nonspecific computerized training (ST, nST), performed in one-hour sessions, twice/week for 3 months. The primary outcome was the effect of the training on global neuropsychological performances measured by the cognitive impairment index (CII). The efficacy of the intervention was evaluated in each disease group by using repeated measures ANOVA.

RESULTS

Sixteen POMS (9 females, age 15.75 ± 1.74 years) and 20 ADHD (2 females, age 11.19 ± 2.49 years) patients were enrolled. In POMS patients the ST exposure was associated to a significantly more pronounced improvement of the CII (p < 0.0001) and on cognitive test exploring attention, concentration, planning strategies and visuo-spatial memory performances in comparison to nST exposure. In ADHD patients the difference between the ST and nST on the CII was not statistical significant (p = 0.06), but a greater effect of the ST was found only on cognitive test exploring attention and delayed recall of visuo-spatial memory performances.

CONCLUSIONS

Our data suggest that a cognitive rehabilitation program that targets attention is a suitable tool for improving global cognitive functioning in POMS patients, whereas it has a less pronounced transfer effect in ADHD patients.

TRIAL REGISTRATION

ClinicalTrials.gov; NCT03190902 ; registration date: June 15, 2017; retrospectively registered.

A Systematic Review of Commercial Cognitive Training Devices: Implications for Use in Sport

Background: Cognitive training (CT) aims to develop a range of skills, like attention and decision-making, through targeted training of core cognitive functions. While CT can target context specific skills, like movement anticipation, much CT is domain general, focusing on core abilities (e.g., selective attention) for transfer to a range of real-world tasks, such as spotting opponents. Commercial CT (CCT) devices are highly appealing for athletes and coaches due to their ease of use and eye-catching marketing claims. The extent to which this training transfers to performance in the sporting arena is, however, unclear. Therefore, this paper sought to provide a systematic review of evidence for beneficial training effects of CCT devices and evaluate their application to sport. Methods: An extensive search of electronic databases (PubMed, PsychInfo, GoogleScholar, and SportDiscus) was conducted to identify peer-reviewed evidence of training interventions with commercially available CT devices. Forty-three studies met the inclusion criteria and were retained for quality assessment and synthesis of results. Seventeen studies assessed transfer effects beyond laboratory cognitive tests, but only 1 directly assessed transfer to a sporting task. Results: The review of evidence showed limited support for far transfer benefits from CCT devices to sporting tasks, mainly because studies did not target the sporting environment. Additionally, a number of methodological issues with the CCT literature were identified, including small sample sizes, lack of retention tests, and limited replication of findings by researchers independent of the commercial product. Therefore, evidence for sporting benefits is currently limited by the paucity of representative transfer tests and a focus on populations with health conditions. Conclusions: Currently there is little direct evidence that the use of CCT devices can transfer to benefits for sporting performance. This conclusion, however, stems more from a lack of experimental studies in the sporting field and a lack of experimental rigor, rather than convincing null effects. Subsequently, there is an opportunity for researchers to develop more reliable findings in this area through systematic assessment in athletic populations and major methodological improvements.

Linking ADHD to the Neural Circuitry of Attention

Attention deficit hyperactivity disorder (ADHD) is a complex condition with a heterogeneous presentation. Current diagnosis is primarily based on subjective experience and observer reports of behavioral symptoms - an approach that has significant limitations. Many studies show that individuals with ADHD exhibit poorer performance on cognitive tasks than neurotypical controls, and at least seven main functional domains appear to be implicated in ADHD. We discuss the underlying neural mechanisms of cognitive functions associated with ADHD, with emphasis on the neural basis of selective attention, demonstrating the feasibility of basic research approaches for further understanding cognitive behavioral processes as they relate to human psychopathology. The study of circuit-level mechanisms underlying executive functions in nonhuman primates holds promise for advancing our understanding, and ultimately the treatment, of ADHD.

Age-related connectivity differences between attention deficit and hyperactivity disorder patients and typically developing subjects: a resting-state functional MRI study

Attention deficit and hyperactivity disorder (ADHD) is a disorder characterized by behavioral symptoms including hyperactivity/impulsivity among children, adolescents, and adults. These ADHD related symptoms are influenced by the complex interaction of brain networks which were under explored. We explored age-related brain network differences between ADHD patients and typically developing (TD) subjects using resting state fMRI (rs-fMRI) for three age groups of children, adolescents, and adults. We collected rs-fMRI data from 184 individuals (27 ADHD children and 31 TD children; 32 ADHD adolescents and 32 TD adolescents; and 31 ADHD adults and 31 TD adults). The Brainnetome Atlas was used to define nodes in the network analysis. We compared three age groups of ADHD and TD subjects to identify the distinct regions that could explain age-related brain network differences based on degree centrality, a well-known measure of nodal centrality. The left middle temporal gyrus showed significant interaction effects between disease status (i.e., ADHD or TD) and age (i.e., child, adolescent, or adult) (P < 0.001). Additional regions were identified at a relaxed threshold (P < 0.05). Many of the identified regions (the left inferior frontal gyrus, the left middle temporal gyrus, and the left insular gyrus) were related to cognitive function. The results of our study suggest that aberrant development in cognitive brain regions might be associated with age-related brain network changes in ADHD patients. These findings contribute to better understand how brain function influences the symptoms of ADHD.