Effects of methylphenidate on cognitive functions in children and adolescents with attention-deficit/hyperactivity disorder: evidence from a systematic review and a meta-analysis

Outcomes of a 12-week ecologically valid observational study of first treatment with methylphenidate in a representative clinical sample of drug naïve children with ADHD

Randomized placebo-controlled trials have reported efficacy of methylphenidate (MPH) for Attention-deficit/hyperactivity disorder (ADHD); however, selection biases due to strict entry criteria may limit the generalizability of the findings. Few ecologically valid studies have investigated effectiveness of MPH in representative clinical populations of children. This independently funded study aims to describe treatment responses and their predictors during the first 12 weeks of MPH treatment using repeated measurements of symptoms and adverse reactions (ARs) to treatment in 207 children recently diagnosed with ADHD. The children were consecutively included from the Child and Adolescent Mental Health Centre, Mental Health Services, The Capital Region of Denmark. The children (mean age, 9.6 years [range 7–12], 75.4% males) were titrated with MPH, based on weekly assessments of symptoms (18-item ADHD-rating scale scores, ADHD-RS-C) and ARs. At study-end 187 (90.8%) children reached a mean end-dose of 1.0 mg/kg/day. A normalisation/borderline normalisation on ADHD-RS-C was achieved for 168 (81.2%) children on the Inattention and/or the Hyperactivity-Impulsivity subscale in week 12, and 31 (15.0%) children were nonresponders, which was defined as absence of normalisation/borderline normalisation (n = 19) or discontinuation due to ARs (n = 12), and eight (3.8%) children dropped out from follow-up. Nonresponders were characterised by more severe symptoms of Hyperactivity-Impulsivity and global impairment before the treatment. ARs were few; the most prominent were appetite reduction and weight loss. A decrease in AR-like symptoms during the treatment period questions the validity of currently available standard instruments designed to measure ARs of MPH. This ecologically valid observational study supports prior randomized placebo-controlled trials; 81.2% of the children responded favourably in multiple domains with few harmful effects to carefully titrated MPH.

Clinical trial registration: ClinicalTrials.gov with registration number NCT04366609.

Cognition during active methamphetamine use versus remission

OBJECTIVE

To evaluate whether cognitive performance in adults with active methamphetamine use (MA-ACT) differs from cognitive performance in adults in remission from MA use disorder (MA-REM) and adults without a history of substance use disorder (CTLs).

METHOD

MA-ACT (n = 36), MA-REM (n = 48), and CTLs (n = 62) completed the Neuropsychological Assessment Battery (NAB).

RESULTS

The MA-ACT group did not perform significantly worse than CTLs on any NAB Index. The MA-REM group performed significantly (p < 0.050) worse than CTLs on the NAB Memory Index. The MA-ACT group performed significantly better than CTLs and the MA-REM group on the Executive Functions Index.

CONCLUSIONS

Some cognitive deficits are apparent during remission from MA use, but not during active use; this may result in clinical challenges for adults attempting to maintain recovery and continue with treatment.

Sevoflurane in electroconvulsive therapy: A systematic review and meta-analysis of randomised trials

Sevoflurane is the most commonly used inhaled anaesthetic in electroconvulsive therapy (ECT). The objective of this study was to provide an up-to-date and comprehensive review on how the use of sevoflurane affects seizure adequacy (seizure duration and postictal suppression index [PSI]) and circulatory dynamics in ECT. We performed a meta-analysis of RCTs that investigated seizure adequacy and circulatory dynamics in patients treated with ECT using sevoflurane (sevoflurane group) and intravenous anaesthetics (non-sevoflurane group). A total of 12 RCTs (377 patients and 1339 ECT sessions) were included. Sevoflurane significantly decreased the electroencephalogram (EEG) seizure durations in comparison with intravenous anaesthetics, whereas no significant difference was observed in PSI (EEG: 9 studies, standardized mean difference (SMD) = 0.74, 95% confidence interval (CI) = -1.11 to -0.38, p = 0.0002; PSI: 4 studies, SMD = -0.06, CI -0.13 to 0.25, p = 0.59). The use of sevoflurane in ECT significantly increased heart rate (HR) compared with intravenous anaesthetics (9 studies, SMD = 0.31, CI 012-0.51, p = 0.004). In the pre-planned subgroup analysis, sevoflurane significantly reduced seizure duration compared with other types of anaesthetics, including propofol, barbiturates and ketamine. Furthermore, it was found that the risk of adverse events in ECT with sevoflurane were not significantly different from intravenous anaesthetics (6 studies, risk ratio = 1.33, CI 0.95-1.86, p = 0.09), with agitaion being the most common adverse effects. The results of our study suggest that using sevoflurane for ECT significantly reduces seizure duration, increases maximum HR and brings about no difference in the adverse event risk compared with those using intravenous anaesthetics for ECT. Therefore, there may not be compelling evidence favouring sevoflurane use for ECT, except in cases where intravenous access is difficult.

Practitioner's review: medication for children and adolescents with autism spectrum disorder (ASD) and comorbid conditions

Alleviating the multiple problems of children with autism spectrum disorder (ASD) and its comorbid conditions presents major challenges for the affected children, parents, and therapists. Because of a complex psychopathology, structured therapy and parent training are not always sufficient, especially for those patients with intellectual disability (ID) and multiple comorbidities. Moreover, structured therapy is not available for a large number of patients, and pharmacological support is often needed, especially in those children with additional attention deficit/hyperactivity and oppositional defiant, conduct, and sleep disorders.

Selective Effects of Methylphenidate on Attention and Inhibition in 22q11.2 Deletion Syndrome: Results From a Clinical Trial

BACKGROUND

Attention deficit and/or hyperactivity disorder (ADHD) is the most prevalent psychiatric disorder in children with 22q11.2 deletion syndrome (22q11DS) and frequently persists into adulthood. Although medication with stimulant has been demonstrated to be highly effective in idiopathic ADHD, evidence in 22q11DS is still scarce. Previous studies have shown safety and effectiveness of methylphenidate (MPH) on core symptoms of ADHD as well as improvement of associated cognitive deficits. However, only a limited number of cognitive domains have been explored.

METHODS

Twenty-three participants with 22q11DS and attention difficulties, aged 8-24 years, entered a clinical trial aiming to specify the effects of MPH on clinical symptoms, cognition, and daily-life behavior. The effects of treatment were compared with/without medication in a within-subject design. The trial included both participants naïve to the molecule and chronic users.

RESULTS

Benefit from the treatment was demonstrated through a decrease in core ADHD symptoms, specifically inattention symptoms, and improvement of cognitive measures of attention and inhibition. Conversely, no significant change was found for other executive functions (such as cognitive flexibility, working memory, initiation), learning, or memory. Moreover, no significant improvement on ecological measures of daily-life executive functioning was found, possibly because of the short treatment period. We replicated safety, and although very frequent, side effects were of mild intensity and comparable with previous findings.

CONCLUSIONS

This study extends the current knowledge on the effects of MPH in patients with 22q11DS. Treatment was found to be effective for core ADHD symptoms and cognitive measures of attention and inhibition.

Neurotherapeutics for Attention Deficit/Hyperactivity Disorder (ADHD): A Review

This review focuses on the evidence for neurotherapeutics for attention deficit/hyperactivity disorder (ADHD). EEG-neurofeedback has been tested for about 45 years, with the latest meta-analyses of randomised controlled trials (RCT) showing small/medium effects compared to non-active controls only. Three small studies piloted neurofeedback of frontal activations in ADHD using functional magnetic resonance imaging or near-infrared spectroscopy, finding no superior effects over control conditions. Brain stimulation has been applied to ADHD using mostly repetitive transcranial magnetic and direct current stimulation (rTMS/tDCS). rTMS has shown mostly negative findings on improving cognition or symptoms. Meta-analyses of tDCS studies targeting mostly the dorsolateral prefrontal cortex show small effects on cognitive improvements with only two out of three studies showing clinical improvements. Trigeminal nerve stimulation has been shown to improve ADHD symptoms with medium effect in one RCT. Modern neurotherapeutics are attractive due to their relative safety and potential neuroplastic effects. However, they need to be thoroughly tested for clinical and cognitive efficacy across settings and beyond core symptoms and for their potential for individualised treatment.

Baseline performance moderates stimulant effects on cognition in youth with ADHD

Attention-deficit/hyperactivity disorder is associated with impaired cognitive functioning and increased delay discounting (i.e., a stronger preference for immediate reward). At the group level, stimulant medication improves cognition and delay discounting, yet not all children exhibit problems in these domains, and previous work has not examined whether stimulant-induced improvements are moderated by baseline performance. To address this question in the current study, 82 children with attention-deficit/hyperactivity disorder (9-12 years old) attended a week-long research camp. On the baseline day (Monday), participants completed tasks of inhibitory control, visuospatial working memory, reaction time variability, and delay discounting. Children then completed a 3-day, randomized, double-blind, placebo-controlled trial of ∼1 mg/kg and 2 mg/kg long-acting methylphenidate (mean doses = 39.1 and 74.3 mg, respectively), during which they were readministered the battery of tasks. Cognitive composites (mean of inhibitory control, working memory, and reaction time variability performance) were created for the baseline and medication evaluation phases. As predicted, the extent to which cognition was improved with medication compared with placebo and with 2 mg/kg compared with 1 mg/kg was greatest among children with poorer baseline cognitive function. Children with stronger baseline cognition exhibited less improvement with methylphenidate compared with placebo and did not benefit from the 2 compared with the 1 mg/kg dose. In contrast, medication-related improvement in delay discounting was unrelated to baseline discounting. Given that improving cognitive function is one potential mechanisms by which stimulants exert their therapeutic effects, this study has significant implications for understanding how and for whom stimulant medication works. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Does Methylphenidate Work in Children and Adolescents with Attention Deficit Hyperactivity Disorder?

OBJECTIVE

Attention deficit hyperactivity disorder (ADHD) is a common psychiatric disorder diagnosed in increasing proportions of children and adolescents. The psychostimulant methylphenidate has been considered the first-line pharmacological treatment for children and adolescents with ADHD for more than 60 years. Considering recent publications on methylphenidate for ADHD, we here give an overview of its effects in children and adolescents with ADHD, elicited by a well-disputed Cochrane review and narratively synthesise the evidence in the field.

METHOD

We searched for systematic reviews and meta-analyses that investigated methylphenidate as an intervention for children and adolescence with ADHD compared with placebo or no treatment. We assessed the quality of the evidence using AMSTAR II.

RESULTS

We found 24 eligible systematic reviews and meta-analyses of which 11 were rated as high- quality evidence according to AMSTAR II. The evidence claiming that methylphenidate is beneficial in treating children and adolescents with ADHD was of very low certainty. The underreporting of adverse events in randomised clinical trials may impede an adequate depiction of the balance between benefits and harms.

CONCLUSIONS

It appears that there is uncertain evidence on group-level to support the claim that methylphenidate is beneficial in treating children and adolescents with ADHD. Future randomised clinical trials and systematic reviews should include individual participant data, which would allow us to assess intervention effects across modifiers, like age, sex, ADHD subtypes, comorbidities, and dose.

Exploring the Effects of Pharmacological, Psychosocial, and Alternative/Complementary Interventions in Children and Adolescents With Attention-Deficit/Hyperactivity Disorder: Meta-Regression Approach

BACKGROUND

There have been various therapies for attention-deficit/hyperactivity disorder (ADHD), but the previous meta-analysis of ADHD efficacy remains unclear. This study aims to systemically meta-regress the effect sizes (ES) of psychostimulant pharmacotherapy (methylphenidate and lisdexamfetamine), non-stimulant pharmacotherapy (atomoxetine and alpha-2 agonists), psychosocial therapy (parental behavioral therapy [PBT]), combination therapy (psychostimulant plus PBT), and alternative/complementary interventions to determine the right treatment for ADHD.

METHODS

We searched various ADHD interventions from the MEDLINE and PubMed databases (National Center for Biotechnology Information) between January 1, 1980, and July 30, 2018. Following the meta-analysis of random effects, the meta-regression analyses were used to explore factors potentially influencing treatment efficacy. The confounding variables included type of treatment, type of study, age, type of symptom scale used, and year of publication.

RESULTS

A total of 107 trials (n = 9883 participants) were included. After adjustment, compared with the psychostimulant therapy (28 trial, 2134 participants), non-stimulant pharmacotherapy (28 trials, 4991 participants) and alternative/complement intervention (25 trials, 1195 participants) were less effective by the ES of -0.384 (P = .004) and -0.419 (P = .028), respectively. However, compared with psychostimulant, PBT (19 trials, 1122 participants; ES = -0.308, P = .095) and the combination of psychostimulant and PBT (7 trials, 441participants; ES = -0.196, P = .209) did not differ significantly.

CONCLUSIONS

Psychostimulant therapy surpassed non-stimulant pharmacotherapy and alternative/complement intervention. Psychostimulant therapy, PBT, and the combination of psychostimulant therapy and PBT appear to be similar in efficacy according to this meta-regression.

Efficacy and acceptability of pharmacological, psychosocial, and brain stimulation interventions in children and adolescents with mental disorders: an umbrella review

Top-tier evidence on the safety/tolerability of 80 medications in children/adolescents with mental disorders has recently been reviewed in this jour-nal. To guide clinical practice, such data must be combined with evidence on efficacy and acceptability. Besides medications, psychosocial inter-ventions and brain stimulation techniques are treatment options for children/adolescents with mental disorders. For this umbrella review, we systematically searched network meta-analyses (NMAs) and meta-analyses (MAs) of randomized controlled trials (RCTs) evaluating 48 medications, 20 psychosocial interventions, and four brain stimulation techniques in children/adolescents with 52 different mental disorders or groups of mental disorders, reporting on 20 different efficacy/acceptability outcomes. Co-primary outcomes were disease-specific symptom reduction and all-cause discontinuation ("acceptability"). We included 14 NMAs and 90 MAs, reporting on 15 mental disorders or groups of mental disorders. Overall, 21 medications outperformed placebo regarding the co-primary outcomes, and three psychosocial interventions did so (while seven outperformed waiting list/no treatment). Based on the meta-analytic evidence, the most convincing efficacy profile emerged for amphetamines, methylphenidate and, to a smaller extent, behavioral therapy in attention-deficit/hyperactivity disorder; aripiprazole, risperidone and several psychosocial interventions in autism; risperidone and behavioral interventions in disruptive behavior disorders; several antipsychotics in schizophrenia spectrum disorders; fluoxetine, the combination of fluoxetine and cognitive behavioral therapy (CBT), and interpersonal therapy in depression; aripiprazole in mania; fluoxetine and group CBT in anxiety disorders; fluoxetine/selective serotonin reuptake inhibitors, CBT, and behavioral therapy with exposure and response prevention in obsessive-compulsive disorder; CBT in post-traumatic stress disorder; imipramine and alarm behavioral intervention in enuresis; behavioral therapy in encopresis; and family therapy in anorexia nervosa. Results from this umbrella review of interventions for mental disorders in children/adolescents provide evidence-based information for clinical decision making.

Association of Pharmacological Interventions With Symptom Burden Reduction in Patients With Mild Traumatic Brain Injury: A Systematic Review

Importance

Mild traumatic brain injury (TBI) is experienced by 55.9 million people globally each year. The symptoms of mild TBI are diverse and sometimes long-lasting, requiring frequent use of pharmacological interventions to mitigate them. A thorough understanding of the data supporting pharmacological interventions is important for decision-making among clinicians treating this common injury.

Objective

To systematically review studies of pharmacological interventions and their associations with symptom burden reduction among patients with mild TBI and to use an evidence-based model to identify potential directions for future research that may aid in clinical decision-making.

Evidence Review

A systematic review was performed in PubMed, Scopus, and Web of Science. Search strings modified for the advanced search interfaces of each search engine were developed in consultation with a librarian and included combinations of search terms, such as brain concussion, post-concussion syndrome, mild traumatic brain injury, and pharmacological treatment. Articles published between January 1, 2000, and July 1, 2020, were analyzed. Studies were included if (1) they were clinical studies with discrete analyses of participants with mild TBI or complicated mild TBI, (2) they were assessments of a pharmacological intervention, (3) they included human participants, and (4) they were published in a peer-reviewed journal in the English language. Studies were excluded if the severity of TBI among participants could not be ascertained (ie, inadequate definition of mild TBI) and the inclusion criteria for the study required intracranial hemorrhage. A total of 23 studies examining 20 pharmacological interventions met the inclusion criteria. Risk of bias was assessed using the Cochrane Risk of Bias for Randomized Trials (for randomized clinical trials) and the Cochrane Risk of Bias in Non-Randomized Studies of Interventions (for all other studies). Data were analyzed from June to September 2020.

Findings

A total of 1495 articles were identified; of those, 131 articles were excluded as duplicates. Titles and abstracts were screened for inclusion and exclusion criteria among the remaining 1364 articles, and 134 of those articles received a full-text review. After exclusions, 23 studies (11 randomized clinical trials, 7 prospective observational studies, 3 retrospective observational studies, and 2 case studies) examining 20 pharmacological interventions were identified for inclusion in the systematic review. Studies included 22 distinct participant populations comprising 8277 participants with mild TBI and 45 participants without TBI. Among 23 total studies, 8 studies specifically addressed the pediatric population, 9 studies had a low risk of bias, and 16 studies reported symptom burden reduction. Of the 20 pharmacological interventions examined in the studies, methylphenidate, sertraline hydrochloride, ondansetron, amitriptyline, and melatonin were the only medications included in multiple studies.

Conclusions and Relevance

This systematic review found a limited number of high-quality, clinically meaningful studies, particularly among children and individuals in the acute stage of injury; therefore, performing an evidence-based analysis that would inform clinical decision-making was not possible. Future studies are needed to focus on standardizing measures and increasing sample sizes (including large multicenter clinical trials) to generate a body of research that may provide additional options for the treatment of patients with mild TBI.

Do effects of methylphenidate on cognitive performance last beyond treatment? A randomized placebo-controlled trial in boys and men with ADHD

Methylphenidate (MPH) is the first-choice pharmacological treatment for treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) across the lifespan. However, it is unclear whether MPH affects cognitive development, while recent (pre-) clinical studies suggest effects on the developing brain. The present randomized, placebo-controlled trial aims to determine whether MPH has short-term, age-dependent effects on cognitive performance in ADHD after a 1-week washout. Effects of 16 weeks MPH treatment were assessed after a one-week washout on cognitive functioning. Boys (age=10-12) and men (age=23-40) with ADHD were assigned to MPH treatment (boys n=25, men n=24) or placebo (boys n=25, men n=24). Outcome measures were working memory, response inhibition, response speed, episodic memory, and delay aversion. Differences in task performances over time (pre-, mid-, and post-treatment, following a 1-week wash-out) were compared between age and treatment conditions with mixed ANOVAs. MPH improved working memory and response speed, but only during treatment. No lasting age*treatment effects were observed post intervention. Overall, the results from the present randomized, placebo-controlled trial show that the effects of MPH on cognition do not extend past treatment in children or adults. While treatment with MPH improves cognition during treatment, these effects appear transient after 16-weeks of treatment. (Title trial: "Effects of methylphenidate on the developing brain"; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3103).

Effects of computerized cognitive training as add-on treatment to stimulants in ADHD: a pilot fMRI study

The neurofunctional effects of Cognitive training (CT) are poorly understood. Our main objective was to assess fMRI brain activation patterns in children with ADHD who received CT as an add-on treatment to stimulant medication. We included twenty children with ADHD from a clinical trial of stimulant medication and CT (10 in medication + CT and 10 in medication + non-active training). Between-group differences were assessed in performance and in brain activation during 3 fMRI paradigms of working memory (N-back: 0-back, 1-back, 2-back, 3-back), sustained attention (Sustained Attention Task - SAT: 2 s, 5 s and 8 s delays) and inhibitory control (Go/No-Go). We found significant group x time x condition interactions in working memory (WM) and sustained attention on brain activation. In N-back, decreases were observed in the BOLD signal change from baseline to endpoint with increasing WM load in the right insula, right putamen, left thalamus and left pallidum in the CT compared to the non-active group; in SAT - increases in the BOLD signal change from baseline to endpoint with increasing delays were observed in bilateral precuneus, right insula, bilateral associative visual cortex and angular gyrus, right middle temporal, precentral, postcentral, superior frontal and middle frontal gyri in the CT compared to the non-active group. CT in ADHD was associated with changes in activation in task-relevant parietal and striato-limbic regions of sustained attention and working memory. Changes in brain activity may precede behavioral performance modifications in working memory and sustained attention, but not in inhibitory control.

Differential Treatment Effects of Methylphenidate and Atomoxetine on Executive Functions in Children with Attention-Deficit/Hyperactivity Disorder

Objectives: This study aimed to compare the efficacy of methylphenidate and atomoxetine on improving executive functions among children with attention-deficit/hyperactivity disorder (ADHD). Methods: This was an open-label, head-to-head, 3-month, randomized clinical trial with two-arm parallel-treatment groups: osmotic-release oral system methylphenidate (OROS-MPH; n = 79) and atomoxetine once daily (n = 78). Three major domains of executive functions were assessed, including response selection/inhibition, flexibility, and planning/working memory. The neuropsychological measures included the Conners' continuous performance test and the Cambridge Neuropsychological Test Automated Battery. Results: We found that both treatment groups showed improvement in executive functions (p-value <0.05 for the major indices of each domain). In addition, OROS-MPH was associated with a greater magnitude of improvement in the response selection/inhibition; the slope for detectability improvement in the Conners' continuous performance test was 0.06 for atomoxetine and 0.15 for OROS-MPH (p-value <0.01); the slope in rapid visual information processing was 2.22 for atomoxetine and 3.45 for OROS-MPH (p-value <0.05). Conclusion: Both OROS-MPH and atomoxetine improved various domains of executive functions in children with ADHD. There is greater improvement in response selection/inhibition among patients treated with OROS-MPH than those with atomoxetine. This trial was registered with ClinicalTrials.gov (no. NCT00916786).

Overdiagnosis of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents: A Systematic Scoping Review

IMPORTANCE

Reported increases in attention-deficit/hyperactivity disorder (ADHD) diagnoses are accompanied by growing debate about the underlying factors. Although overdiagnosis is often suggested, no comprehensive evaluation of evidence for or against overdiagnosis has ever been undertaken and is urgently needed to enable evidence-based, patient-centered diagnosis and treatment of ADHD in contemporary health services.

OBJECTIVE

To systematically identify, appraise, and synthesize the evidence on overdiagnosis of ADHD in children and adolescents using a published 5-question framework for detecting overdiagnosis in noncancer conditions.

EVIDENCE REVIEW

This systematic scoping review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Extension for Scoping Reviews and Joanna Briggs Methodology, including the PRISMA-ScR Checklist. MEDLINE, Embase, PsychINFO, and the Cochrane Library databases were searched for studies published in English between January 1, 1979, and August 21, 2020. Studies of children and adolescents (aged ≤18 years) with ADHD that focused on overdiagnosis plus studies that could be mapped to 1 or more framework question were included. Two researchers independently reviewed all abstracts and full-text articles, and all included studies were assessed for quality.

FINDINGS

Of the 12 267 potentially relevant studies retrieved, 334 (2.7%) were included. Of the 334 studies, 61 (18.3%) were secondary and 273 (81.7%) were primary research articles. Substantial evidence of a reservoir of ADHD was found in 104 studies, providing a potential for diagnoses to increase (question 1). Evidence that actual ADHD diagnosis had increased was found in 45 studies (question 2). Twenty-five studies showed that these additional cases may be on the milder end of the ADHD spectrum (question 3), and 83 studies showed that pharmacological treatment of ADHD was increasing (question 4). A total of 151 studies reported on outcomes of diagnosis and pharmacological treatment (question 5). However, only 5 studies evaluated the critical issue of benefits and harms among the additional, milder cases. These studies supported a hypothesis of diminishing returns in which the harms may outweigh the benefits for youths with milder symptoms.

CONCLUSIONS AND RELEVANCE

This review found evidence of ADHD overdiagnosis and overtreatment in children and adolescents. Evidence gaps remain and future research is needed, in particular research on the long-term benefits and harms of diagnosing and treating ADHD in youths with milder symptoms; therefore, practitioners should be mindful of these knowledge gaps, especially when identifying these individuals and to ensure safe and equitable practice and policy.

Cognitive mechanisms of methylphenidate in ADHD: Do improvements in sustained attention mediate behavioral improvements in the natural environment?

The relation between sustained attention in the laboratory and behaviors exhibited in naturalistic settings among children with Attention Deficit/Hyperactivity Disorder (ADHD) remains unclear. Additionally, research on stimulant medication effects in these areas and their association with one another remains scarce. Twenty-one children with ADHD and 21 children without ADHD completed a novel continuous performance test (CPT) involving high cognitive demands (e.g., visual search). Participants with ADHD also attended a Summer Treatment Program and received three doses of stimulant medication (placebo, low, and high). Their behavior in classroom and peer settings was observed and recorded, and they completed the CPT in each medication condition. The CPT measures of bias and sensitivity were used in analyses. Results indicated that children with ADHD had impaired overall performance and worse bias during the second half of the task compared to controls. Methylphenidate improved both naturalistic behavior and overall CPT performance but did not specifically improve the sustained attention deficit. Despite improvements in overall CPT performance, medication-related improvement in CPT performance did not mediate medication-related improvement in observed behavior in classroom or recreational settings. As such, our findings suggest that although children with ADHD do demonstrate a sustained attention deficit, salutary psychostimulant effects on CPT performance are not indicative of, or causally linked to, psychostimulant effects on presenting problems in naturalistic settings.

Methylphenidate for attention problems in epilepsy patients: Safety and efficacy

Children with attention deficit hyperactivity disorder (ADHD) have an increased risk of seizures, and children with epilepsy have an increased prevalence of ADHD. Adults with epilepsy often have varying degrees of attentional dysfunction due to multiple factors, including anti-seizure medications, frequent seizures, interictal discharges, underlying lesions, and psychiatric comorbidities. Currently, there are no approved medications for the treatment of epilepsy-related attentional dysfunction. Methylphenidate (MPH) is a stimulant, FDA-approved for the treatment of ADHD, and often used for ADHD in the setting of pediatric epilepsy. Large database and registry studies indicate safety of MPH in children with ADHD and epilepsy, with no significant effect on seizure frequency. Small single-dose and open-label studies suggest efficacy of MPH in adults with epilepsy-related attention deficits. Methylphenidate represents a possible treatment for attentional dysfunction due to epilepsy, but large, randomized, placebo-controlled, double-blinded studies are needed.

The Visuo-Motor Attention Test in Boys with Attention Deficit Hyperactivity Disorder (ADHD): Methylphenidate-Placebo Randomized Controlled Trial

To assess the visuomotor attention ability in children with ADHD and controls and their response to placebo and Methylphenidate (MPH) treatment. 36 boys with ADHD and 36 age matched typical controls were administered the visuomotor attention test (VMAT) as a baseline and following a week of MPH(IR) or placebo administered to the study group, in a randomized crossover design. A significant difference between the study and control groups was found on several VMAT measures. No performance difference between ADHD dimensional sub-types was observed at the baseline assessment. Under MPH treatment a significant improvement in VMAT measures was observed and particularly in the combined and predominantly hyperactive (C\HI) type. The VMAT results obtained in the present study are consistent with previous findings. ADHD subtypes appear similarly short of visuomotor attention resources; a visuomotor test can be used in the assessment of gains derived from MPH treatment.

Attention-deficit/hyperactivity disorder and the explore/exploit trade-off

The ability to maximize rewards and minimize the costs of obtaining them is vital to making advantageous explore/exploit decisions. Exploratory decisions are theorized to be greater among individuals with attention-deficit/hyperactivity disorder (ADHD), potentially due to deficient catecholamine transmission. Here, we examined the effects of ADHD status and methylphenidate, a common ADHD medication, on explore/exploit decisions using a 6-armed bandit task. We hypothesized that ADHD participants would make more exploratory decisions than controls, and that MPH would reduce group differences. On separate study days, adults with (n = 26) and without (n = 23) ADHD completed the bandit task at baseline, and after methylphenidate or placebo in counter-balanced order. Explore/exploit decisions were modeled using reinforcement learning algorithms. ADHD participants made more exploratory decisions (i.e., chose options without the highest expected reward value) and earned fewer points than controls in all three study days, and methylphenidate did not affect these outcomes. Baseline exploratory choices were positively associated with hyperactive ADHD symptoms across all participants. These results support several theoretical models of increased exploratory choices in ADHD and suggest the unexplained variance in ADHD decisions may be due to less value tracking. The inability to suppress actions with little to no reward value may be a key feature of hyperactive ADHD symptoms.

Effects of a five-day HD-tDCS application to the right IFG depend on current intensity: A study in children and adolescents with ADHD

Impaired executive functions in ADHD are associated with hypoactivity of the right inferior frontal gyrus (IFG). This region was targeted via repetitive applications of anodal, high-definition transcranial direct current simulation (HD-tDCS) on five consecutive days in 33 ADHD patients (10-17years) and in a healthy control group (n=13, only sham). Patients received either sham (n=13) or verum tDCS with 0.5mA (n=9) or 0.25mA (n=11) depending on individual cutaneous sensitivity. During stimulation, participants performed a combined working memory and response inhibition paradigm (n-back/nogo). At baseline, post, and a 4-month follow up, electroencephalography was recorded during this task. Moreover, interference control (flanker task) and spatial working memory (spanboard task) were assessed to explore possible transfer effects. Omission errors and reaction time variability in all tasks served as measures of attention. In the 0.25mA group increased nogo commission errors indicated a detrimental tDCS effect on response inhibition. After the 5-day stimulation, attentional improvements in the 0.5mA group were indicated by reduced omission errors and reaction time variability. Variability improvements were still evident at follow up. In all groups, nogo P3 amplitudes were reduced post-stimulation, but in the 0.5mA group this reduction was smaller than in the 0.25mA group. Results of the current study suggest distinct effects of tDCS with different current intensities demonstrating the importance of a deeper understanding on the impact of stimulation parameters and repeated tDCS applications to develop effective tDCS-based therapy approaches in ADHD.

Computerized Cognitive Training for ADHD as an Add-On Treatment to Stimulants: A Randomized Clinical Trial

Objective: Computerized cognitive training (CCT) as add-on treatment to stimulants for ADHD core symptoms is scarcely investigated. The purpose of this study is to assess the effect of CCT in a randomized controlled clinical trial for ADHD in children and adolescents treated with stimulants. Method: Fifty-three participants aged 6 to 13 years receiving stimulant treatment and presenting ADHD residual symptoms were randomized either to a CCT (n = 29) or to a controlled nonactive condition (n = 24) for four sessions/week during 12 weeks. The main outcome measure was inattentive symptoms assessed using the Swanson, Nolan, and Pelham-IV (SNAP-IV) Scale. Secondary outcomes include, among others, hyperactive/impulsive symptoms and cognitive tests. Results: There were neither significant group differences on ADHD-inattentive symptoms after the intervention nor on both ADHD-hyperactivity/impulsivity symptoms and cognitive measures. Conclusion: Our study does not provide evidence for the benefits of cognitive training over nonactive training on core ADHD symptoms in medicated ADHD children and adolescents.

The Impact of Methylphenidate on QbTest Performance of Children with ADHD: A Retrospective Clinical Study

INTRODUCTION

The Quantified behavior Test (QbTest), which combines a continuous performance task (CPT) and motion tracking, provides data for the core signs of attention-deficit/hyperactivity disorder (ADHD): attention, hyperactivity, and impulsivity. This study aimed to evaluate the performance of children and adolescents with ADHD on the QbTest before and after a single methylphenidate (MPH) dose.

SUBJECTS AND METHODS

This retrospective chart review study included data from 149 children and 215 adolescents who completed the QbTest. A summary index of the CPT and motion capture data on the QbTest is provided by three cardinal parameters: QbActivity, QbImpulsivity, and QbInattention. The test was performed twice on the same day, before and up to three hours after MPH intake. A decrease by ≥ 0.5 in a cardinal parameter score was considered an improvement, whereas an increase by ≥ 0.5 a deterioration.

RESULTS

QbActivity improvement after MPH intake was present in 71.7% and 76.2% of the children and adolescents, respectively. QbImpulsivity improvement was observed in 50.4% of the children and 44.7% of the adolescents, and QbInattention improvement in 85.1% and 91.1% of the children and adolescents, respectively. All three parameters improved simultaneously in 27.7% of the children and 28.7% of the adolescents. The likelihood that one parameter deteriorated after MPH use was greater if that parameter was within the normal range before medication. This was most pronounced for QbImpulsivity. Among male adolescents, QbInattention improvement was often accompanied by QbImpulsivity deterioration.

CONCLUSION

The QbTest inattention and motor activity parameters improved markedly after a single MPH dose in children and adolescents with ADHD, while less so for impulsivity. Improvement of one parameter is not necessarily associated with improvement of the other two, and deterioration, especially regarding impulsivity, may occur. If confirmed, these results highlight the need for optimization and individualization of MPH treatment, while monitoring all aspects of the ADHD symptomatology based on the QbTest performance.

Neural generators involved in visual cue processing in children with attention-deficit/hyperactivity disorder (ADHD)

Event-related potentials (ERP) studies report alterations in the ongoing visuo-attentional processes in children with attention-deficit/hyperactivity disorder (ADHD). We hypothesized that the neural generators progressively recruited after a cue stimulus imply executive-related areas well before engagement in executive processing in children with ADHD compared to typically developed children (TDC). We computed source localization (swLORETA) of the ERP and ERSP evoked by the Cue stimulus during a visual Cue-Go/Nogo paradigm in 15 ADHD compared to 16 TDC. A significant difference in N200/P200 amplitude over the right centro-frontal regions was observed between ADHD and TDC, supported by a stronger contribution of the left visuo-motor coordination area, premotor cortex, and prefrontal cortex in ADHD. In addition, we recorded a greater beta power spectrum in ADHD during the 80-230 ms interval, which was explained by increased activity in occipito-parieto-central areas and lower activity in the left supramarginal gyrus and prefrontal areas in ADHD. Successive analysis of the ERP generators (0-500 ms with successive periods of 50 ms) revealed significant differences beginning at 50 ms, with higher activity in the ventral anterior cingulate cortex, premotor cortex, and fusiform gyrus, and ending at 400-500 ms with higher activity of the dorsolateral prefrontal cortex and lower activity of the posterior cingulate cortex in ADHD compared to TDC. The areas contributing to ERP in ADHD and TDC differ from the early steps of visuo-attentional processing and reveal an overinvestment of the executive networks interfering with the activity of the dorsal attention network in children with ADHD.

Methylphenidate-Related Improvements in Math Performance Cannot Be Explained by Better Cognitive Functioning or Higher Academic Motivation: Evidence From a Randomized Controlled Trial

Objective: This study investigated whether improvements in working memory, reaction time, lapses of attention, interference control, academic motivation, and perceived competence mediated effects of methylphenidate on math performance. Method: Sixty-three children (ADHD diagnosis; methylphenidate treatment; age 8-13; IQ > 70) were randomly allocated to a 7-day methylphenidate or placebo treatment in this double-blind placebo-controlled crossover study and compared with 67 controls. Data were collected at schools and analyzed using mixed-model analysis. Methylphenidate was hypothesized to improve all measures; all measures were evaluated as potential mediators of methylphenidate-related math improvements. Results: Controls mostly outperformed the ADHD group. Methylphenidate did not affect measures of cognitive functioning (p = .082-.641) or academic motivation (p = .199-.865). Methylphenidate improved parent ratings of their child's self-perceived competence (p < .01), which mediated methylphenidate efficacy on math productivity. Conclusion: These results question the necessity of improvements in specific cognitive and motivational deficits associated with ADHD for medication-related academic improvement. They also stimulate further study of perceived competence as a mediator.

Creativity and ADHD: A review of behavioral studies, the effect of psychostimulants and neural underpinnings

Attention deficit/hyperactivity disorder (ADHD) is a debilitating disorder and most research therefore focuses on its deficits and its treatment. Research on the potential positive sides of ADHD is limited, and although a comprehensive overview of empirical studies on this subject is missing, it has been suggested that ADHD is associated with enhanced creativity. To identify important relations, trends and gaps in the literature, we review 31 behavioral studies on creativity and ADHD, distinguishing different research designs, age groups, creativity measurements and effects of psychostimulants, as well as reflecting the potential underlying neural mechanisms of creativity and ADHD. Most studies find evidence for increased divergent thinking for those with high ADHD scores (subclinical) but not for those with the disorder (clinical). The rates of creative abilities/achievements were high among both clinical and subclinical groups. We found no evidence for increased convergent thinking abilities in ADHD, nor did we find an overall negative effect of psychostimulants on creativity. Neuroscientific findings suggest candidate regions as well as mechanisms that should be studied further to increase our understanding of the relationship between creativity and ADHD. We propose research opportunities to boost the knowledge needed to better understand the potential positive side of ADHD.

Is Methylphenidate Beneficial and Safe in Pharmacological Cognitive Enhancement?

Nootropics are drugs used to either treat or benefit cognition deficits. Among this class, methylphenidate is a popular agent, which acts through indirect dopaminergic and noradrenergic agonism and, therefore, is proposed to enhance performance in catecholamine-dependent cognitive domains such as attention, memory and prefrontal cortex-dependent executive functions. However, investigation into the efficacy of methylphenidate as a cognitive enhancer has yielded variable results across all domains, leading to debate within the scientific community surrounding its off-label use in healthy individuals seeking scholaristic benefit or increased productivity. Through analysis of experimental data and methodological evaluation, it is apparent that there are dose-, task- and domain-dependent considerations surrounding the use of methylphenidate in healthy individuals, whereby tailored dose administration is likely to provide benefit on an individual basis dependent on the domain of cognition in which benefit is required. Additionally, it is apparent that there are subjective effects of methylphenidate, which may increase user productivity irrespective of cognitive benefit. Whilst there is not extensive study in healthy older adults, it is plausible that there are dose-dependent benefits to methylphenidate in older adults in selective cognitive domains that might improve quality of life and reduce fall risk. Methylphenidate appears to produce dose-dependent benefits to individuals with attention-deficit/hyperactivity disorder, but the evidence for benefit in Parkinson's disease and schizophrenia is inconclusive. As with any off-label use of pharmacological agents, and especially regarding drugs with neuromodulatory effects, there are inherent safety concerns; epidemiological and experimental evidence suggests there are sympathomimetic, cardiovascular and addictive considerations, which might further restrict their use within certain demographics.

Longitudinal Trajectories of Sustained Attention Development in Children and Adolescents with ADHD

The present study characterizes changes in sustained attention ability over ages 9-14, and whether longitudinal trajectories of attention development differ between persistent ADHD, remitted ADHD and control groups. The Sustained Attention to Response Task (SART) was administered to 120 children with ADHD and 123 controls on three occasions between ages 9 and 14. Trajectories of sustained attention development, indicated by changes in SART performance (standard deviation of response time [SDRT], omission errors, and ex-Gaussian parameters sigma and tau), were examined using generalized additive mixed models. For all measures there was a significant main effect of age; response time variability and number of omission errors improved linearly as children aged. However, children with ADHD had significantly greater SDRT, tau and omission errors than controls across waves. There were no significant group differences in sigma, indicating that the greater overall response time variability (SDRT) observed in ADHD was likely driven by more intermittent long responses (larger tau). Trajectories of sustained attention performance did not differ between children with persistent ADHD or ADHD in remission. Longitudinal trajectories of sustained attention development are comparable between ADHD and controls, however children with ADHD (regardless of remission status) display a performance deficit equivalent to typical controls 1-3 years younger. Findings highlight the need for continued clinical support for children in remission from ADHD and provide support for tau as an endophenotype of ADHD.

Is sustained attention deficit related to subclinical obsessive thoughts in children and adolescents with ADHD?

Background: Thought content and its impact on sustained attention in individuals with attention deficit hyperactivity disorder (ADHD) are topics of growing interest in literature.Objective: We hypothesised that subclinical obsessive thoughts may be correlated with attention lapses in individuals with ADHD.Method: Thirty children diagnosed with ADHD participated in the study and their level of subclinical obsessive thoughts, attention, and executive function were measured using Children Yale-Brown Obsessive Scale and Conners' Continuous Performance Test II.Results: No significant correlation between sustained attention impairment and the level of obsessive thoughts in patients with ADHD was found. Nevertheless, patients with ADHD with subclinical obsessive thoughts showed more commission errors than those without (W = 51.5; p = 0.02).Conclusion: The nature of thought content in individuals with ADHD should be linked to executive dysfunction rather than attentional impairment. This could be of importance in the therapeutic strategy choice, addressing the importance of executive function remediation in the specific context of subclinical obsessive thoughts.Key points Patients with ADHD, without OCD or ASD comorbidity, still present subclinical obsessive thoughts (36% of our sample).  • Subclinical obsessive thoughts could be a part of thought content in patients with ADHD. • Subclinical obsessive thoughts as measured by the CPT-II are not correlated with attention function in patients with ADHD. • ADHD patients with subclinical obsessive symptoms present more impairment in response inhibition than the ones without. • Results on subclinical obsessive thoughts are similar to those on another type of thought content called 'mind wandering'. • A clinical improvement strategy for patients with ADHD could be using executive function remediation rather than classical attention function remediation, according to both to our and previous results.

The interactive effects of test-retest and methylphenidate administration on cognitive performance in youth with ADHD: A double-blind placebo-controlled crossover study

Studies have shown that Methylphenidate (MPH) affects cognitive performance on the neuropsychological tests and clinical symptoms of individuals diagnosed with attention deficit/hyperactivity disorder (ADHD). This study investigated the acute effects of MPH on neuropsychological tests to explore the interaction between MPH and test-retest effects. Twenty youths with ADHD were tested before and after MPH intake in a double-blind placebo-controlled crossover design and compared to twenty matched controls. Participants were tested on a range of standardized tasks including sustained attention to response, N-Back, and Word/Color Stroop. Identical tasks were administered twice each testing day, before and 1 hour after MPH/Placebo administration. Healthy controls were tested similarly with no intervention. Decreases in response time (RT) variability across tasks and in commission errors were found in ADHD after MPH. Conversely, a significant increase in RT variability and increase in omission errors were observed after the placebo. In the control group, RT variability and omission errors increased whereas commission errors decreased, suggesting fatigue and practice effects, respectively. Test-retest reliability was higher in controls than ADHD. It is suggested that cognitive tests are sensitive objective measures for the assessment of responses to MPH in ADHD but are also affected by repetition and fatigue.

Osmotic Release Oral System-Methylphenidate Hydrochloride (OROS-MPH) versus atomoxetine on executive function improvement and clinical effectiveness in ADHD: A randomized controlled trial

OBJECTIVES

The aim of this study to compare the clinic efficacy and effects of osmotic release oral system-methylphenidate and atomoxetine on executive function in children and adolescents with attention deficit hyperactivity disorder by a open-label, prospective, randomized controlled trial.

METHODS

The study was performed by 95 cases between ages 6 and 12 years who were diagnosed as attention-deficit/hyperactivity disorder (ADHD) and also 40 control individuals. In this study, Conners' Teacher Rating Scale (CTRS) was used in order to evaluate the efficacy of the treatment. Executive functions were assessed by the performance-based neuropsychological tests and ecological behavioral rating scales. Stroop test, cancellation test, and serial digit learning test were applied to performance based neuropsychological tests. Behavior Rating Inventory of Executive Function tests (BRIEFs) were used as behavioral assessment scales.

RESULTS

Among the ADHD groups, a reduction of over 40% in the CTRS subtest scores used to evaluate the efficacy of the treatment was considered to be an improvement, and no significant difference was found for both drugs. Both Osmotic Release Oral System-Methylphenidate Hydrochloride (OROS-MPH) and atomoxetine (ATX) significantly improved scores in neuropsychological tests.

CONCLUSION

Atomoxetine and OROS-MPH treatments have shown similar efficacy in clinical recovery and improvement on executive functions. However, disturbances in executive functions observed in children with ADHD are persistent despite treatment, when compared with the control group.

Attention-Deficit/Hyperactivity Disorder Medication and Unintentional Injuries in Children and Adolescents

OBJECTIVE

Our objective was to determine whether attention-deficit/hyperactivity disorder (ADHD) medication is associated with a decreased risk of unintentional injuries in children and adolescents in the United States across sexes, age groups and injury types.

METHOD

We used de-identified inpatient, outpatient, and filled prescription claims data from the Truven Health MarketScan Research Databases. Individuals were followed from January 1, 2005, date of first ADHD diagnosis, or medication prescription, or age 6 years, whichever occurred last, until December 31, 2014, first healthcare insurance disenrollment, or the first year at which their age was recorded as 19 years, whichever occurred first. A person was considered on ADHD medication during a given month if a prescription was filled in that month. The outcome was defined as emergency department visits for injuries, including traumatic brain injuries, with unintentional causes. Odds of having the outcome were compared between medicated and unmedicated months at the population-level and in within-individual analyses using logistic regression.

RESULTS

Among 1,968,146 individuals diagnosed with ADHD or receiving ADHD medication, 87,154 had at least one event. At the population level, medication use was associated with a lower risk of injuries, both in boys (odds ratio [OR] = 0.85; 95% CI = 0.84-0.86) and girls (OR = 0.87; 95% CI = 0.85-0.89). Similar results were obtained from within-individual analysis among male (OR = 0.72; 95% CI = 0.70-0.74) and female (OR = 0.72; 95% CI = 0.69-0.75) children, and among male (OR = 0.64; 95% CI = 0.60-0.67) and female (OR = 0.65; 95% CI = 0.60-0.71) adolescents. Similar results were found for traumatic brain injuries.

CONCLUSION

ADHD medication use was associated with a reduction of different types of unintentional injuries in children and adolescents of both sexes.

Literacy and Numeracy Underachievement in Boys and Girls With ADHD

Objective: To determine literacy and numeracy outcomes, among children with and without ADHD by gestational age and gender. Method: De-identified linked population data from the Western Australian Monitoring of Drug Dependence Systems, Western Australian Literacy and Numeracy Assessment database, and the Midwives Notification System used information on 6,819 children with ADHD compared with 14,451 non-ADHD children. Results: Twenty-three percent of boys and 28% of girls with ADHD had numeracy scores below the benchmark in School Year 3, compared with 11% of children without ADHD. These differences were also evident in reading, writing, and spelling through primary school. Children with ADHD and reduced gestational age were at a greater risk of not meeting numeracy and reading benchmarks, compared with children born at term. Conclusion: Children with ADHD are disadvantaged from an early age in key areas of learning, and this risk increased with reduction in gestational age at birth.

Measurement of executive functioning with the National Institute of Health Toolbox and the association to anxiety/depressive symptomatology in childhood/adolescence

INTRODUCTION

Despite preliminary research, there remain inconsistent findings with regard to the role of executive functioning (EF) deficits in childhood anxiety and depression. This report examined the association of The National Institute of Health (NIH) Toolbox to clinical neuropsychological measures and to childhood, anxiety/depressive symptomatology. Methods: One-hundred eight children and adolescents completed the three EF measures from the NIH Toolbox (List Sorting Working Memory Test [LSWMT], Dimensional Change Card Sorting Test [DCCST], and Flanker Test of Attention and Inhibition [Flanker]) in an outpatient neuropsychology program. These tests were compared to established measures of EF in terms of linear correlations and detection of impairment. Heaton's Global Deficit Score (GDS) was utilized to calculate impairment. The Toolbox-EF measures were paired with parent-reported EF symptoms (Behavior Rating Inventory of Executive Function [BRIEF2]) to identify the role of EF in childhood anxiety/depressive symptomatology.

RESULTS

Toolbox-EF measures displayed medium sized correlations with their clinically comparable counterparts, and generally did not differ in their detection of impairment. Toolbox-GDS was associated with depression diagnosis and clinically significant child-reported anxiety and depressive symptoms. Together, Toolbox/BRIEF2 accounted for 26.8-30.9% of elevated depressive symptom variance, but only 13.2-14% of elevated anxiety symptom variance. Further, EF impairment was associated with depression across self report, parent report, and clinical diagnosis.

DISCUSSION

The NIH Toolbox-EF measures display comparable psychometric properties to clinically available EF measures in a pediatric (primarily psychiatric) neuropsychology setting. The Toolbox appears to display an appropriate ability to detect EF deficits secondary to self-reported depression in childhood.

The Course of Neurocognitive Functioning and Prediction of Behavioral Outcome of ADHD Affected and Unaffected Siblings

Longitudinal studies on the course of neurocognitive functioning of children with ADHD and their unaffected siblings are scarce. Also, it is unclear to what extent that course is related to ADHD outcomes. A carefully phenotyped large sample of 838 Caucasian participants (ADHD-combined type: n = 339, unaffected siblings: n = 271, controls: n = 228; mean age at baseline = 11.4 years, mean age at follow-up = 17.3 years, SD = 3.2) was used to investigate differences in the course of neurocognitive functioning of ADHD affected and unaffected siblings versus controls, and to investigate the relationship between neurocognitive change and ADHD outcomes. At baseline, an aggregated measure of overall neurocognitive functioning and eight neurocognitive measures of working memory, timing (speed/variability), motor control, and intelligence were investigated. Outcomes at follow-up were dimensional measures of ADHD symptom severity and the Kiddie-Global Assessment Scale (K-GAS) for overall functioning. At follow up, affected and unaffected siblings trended to, or fully caught up with performance levels of controls on four (44.4%) and five (55.6%) of the nine dependent variables, respectively. In contrast, performance in remaining key neurocognitive measures (i.e. verbal working memory, variability in responding) remained impaired at follow-up. Change in neurocognitive functioning was not related to ADHD outcomes. Our results question the etiological link between neurocognitive deficits and ADHD outcomes in adolescents and young adults.

An update on the clinical pharmacology of methylphenidate: therapeutic efficacy, abuse potential and future considerations

INTRODUCTION

Methylphenidate remains a first-line medication for treating ADHD in children and adults. However, its behavioral pharmacological similarities to methamphetamine and cocaine have historically created concern for its potential as a drug of abuse. In September 2019, the FDA published a docket requesting comments for the development of abuse deterrent formulations for CNS stimulants, emphasizing the abuse of methylphenidate as a public health concern.

AREAS COVERED

We conducted a narrative review of research on the clinical pharmacology, therapeutic efficacy, and abuse potential of methylphenidate.

EXPERT OPINION

Several studies indicate that methylphenidate has at least some abuse potential. Methylphenidate, amphetamine, methamphetamine, and cocaine overlap in their subjective, reinforcing, and discriminative stimulus effects. Regardless, methylphenidate remains an efficacious treatment for ADHD in children and adults when properly adhered to, especially when paired with non-pharmacological treatments. The development of abuse deterrent formulations of methylphenidate is warranted.

The association between neurocognition and sexual abuse within a children's psychiatric inpatient program

Objective: The aim of this study was to understand the detrimental effects of sexual abuse on neuropsychological variables including child's intelligence, executive functioning (EF), and learning/memory within a pediatric inpatient population.Method: This study examined the effect of sexual abuse on children's intelligence, EF, and learning/memory by conducting a retrospective chart review for 144 children (aged 7-12) who completed a neuropsychological assessment during a psychiatric inpatient hospitalization. Of the 144 children, participants were matched two to one by gender and age, with one group (n = 52) categorized by reported sexual abuse and the other group (n = 92) categorized by no reported sexual abuse. The neuropsychological measures included the Wechsler Abbreviated Scale of Intelligence (WASI-I/II) or Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV), Wide Range Assessment of Memory and Learning - Second Edition (WRAML-2): Story Memory Immediate/Delayed Recall and Delayed Recognition, Trail Making Test-B, Stroop Interference Test: Color-Word Condition, WRAML-2: Sentence Memory and Conners Continuous Performance Test-Second Edition.Results: Statistical analysis showed that participants with reported sexual abuse had significantly (p< .05) lower intelligence, EF, and learning/memory skills than those without reported sexual abuse. Only working memory and cognitive flexibility differences remained after controlling for clinical variables (e.g., PTSD, amount of total abuse types).Conclusions: These findings contributed to the limited research on the detrimental effects of sexual abuse in a pediatric inpatient population. They demonstrated a relationship between early sexual abuse and neuropsychological deficits, specifically executive function and IQ deficits.

Literacy and Numeracy Underachievement in Boys and Girls With ADHD

Objective: The aim was to determine literacy and numeracy outcomes, among children with and without ADHD by gestational age and gender. Method: De-identified linked population data from the Western Australian Monitoring of Drugs of Dependence System and Western Australian Literacy and Numeracy Assessment databases, and the Midwives Notification System used information on 6,819 children with ADHD compared with 14,451 non-ADHD children. Results: A total of 23% of boys and 28% of girls with ADHD had numeracy scores below the benchmark in School Year 3, compared with 11% of children without ADHD. These differences were also evident for reading, writing, and spelling through primary school. Children with ADHD and reduced gestational age were at a greater risk of not meeting numeracy and reading benchmarks, compared with children born at term. Conclusion: Children with ADHD are disadvantaged from an early age in key areas of learning, and this risk increased with reduction in gestational age at birth.

Increased left inferior fronto-striatal activation during error monitoring after fMRI neurofeedback of right inferior frontal cortex in adolescents with attention deficit hyperactivity disorder

Attention Deficit/Hyperactivity Disorder (ADHD) is a self-regulation disorder, with impairments in error monitoring associated with underactivation of the related brain network(s). Psychostimulant medication improves ADHD symptoms and can upregulate brain function, but has side effects, with limited evidence for longer-term effects. Real-time functional magnetic resonance neurofeedback (fMRI-NF) has potential longer-term neuroplastic effects. We previously reported the effects of 11 runs of 8.5 min of fMRI-NF of the right inferior frontal cortex (rIFC) in adolescents with ADHD. This resulted in improvement of clinical symptom and enhanced rIFC activation post-pre treatment during response inhibition, when compared to a control group receiving fMRI-NF of the left parahippocampal gyrus (lPHG). In the current study we applied a novel analysis to the existing data by investigating the effects of fMRI-NF of rIFC in 16 adolescents with ADHD compared to fMRI-NF of lPHG in 11 adolescents with ADHD on the neurofunctional correlates of error monitoring during the same fMRI tracking stop task and potential associations with cognitive and clinical measures. We found stronger performance adjustment to errors in the rIFC-NF compared to the control lPHG-NF group. At the brain function level, fMRI-NF of rIFC compared to that of lPHG was associated with increased activation in error monitoring regions of the left IFC, premotor cortex, insula and putamen. The increased activation in left IFC-insular-striatal error monitoring regions in the rIFC-NF relative to the lPHG-NF group was furthermore trend-wise correlated with NF-induced ADHD symptom improvements. The findings of this study show, that during error monitoring, fMRI-NF training of rIFC upregulation elicited improvement in post-error behavioural adjustments and concomitant increased activation in left hemispheric fronto-insular-striatal and premotor regions mediating self-control and self-monitoring functions. This suggests that the administration of fMRI-NF of the rIFC may have had an impact on wider networks of self-regulation and self-monitoring in adolescents with ADHD.

Acute Physical Activity, Executive Function, and Attention Performance in Children with Attention-Deficit Hyperactivity Disorder and Typically Developing Children: An Experimental Study

A growing number of studies support the theory that physical activity can effectively foster the cognitive function of children with attention-deficit hyperactivity disorder (ADHD). The present study examines the effect of acute moderate physical activity on the executive functions and attention performance of (1) typically developing children (without psychological, psychiatric or neurological diagnosis and/or associated treatment stated in their medical history); (2) treatment-naïve ADHD children; and (3) medicated children with ADHD. In the current study, a total sample of 150 (50 non-medicated, 50 medicated, and 50 typically developing) children between the ages of 6 and 12 took part in the experiment. The Mini International Neuropsychiatric Interview for Children and Adolescents (MINI Kid) was used to measure ADHD and the child version of the Test of Attentional Performance (KiTAP) was applied to evaluate the children’s attentional and executive function performance before and after two types of intervention. In order to compare the effects of physical activity and control intervention, half of the children from each group (25 participants) took part in a 20-min long, moderately intense physical activity session on the 60–80% of their maximum heart rate, while watching a cartoon video. In the control condition, the other half of the children (25 participants) from each group watched the same cartoon video for 20 min while seated. Physical activity (compared to the just video watching control condition) had a significantly positive influence on 2 out of 15 measured parameters (median reaction time in the alertness task and error rates in the divided attention task) for the medicated group and on 2 out of the 15 measured variables (number of total errors and errors when distractor was presented, both in the distractibility task) regarding the treatment-naïve group. Future studies should focus on finding the optimal type, intensity, and duration of physical activity that could be a potential complementary intervention in treating deficits regarding ADHD in children.

Does ACT-Group Training Improve Cognitive Domain in Children with Attention Deficit Hyperactivity Disorder? A Single-Arm, Open-Label Study

This single-arm, open-label study aimed to investigate the efficacy of a cognitive-behavioural group training based on acceptance and commitment therapy (ACT) on cognition in drug-naïve children with attention deficit hyperactivity disorder (ADHD). Thirty-six children with ADHD aged 8–13 were invited to participate in the 9-month ACT training programme, which consisted of 26 weekly sessions of group therapy lasting 90 min each. Their parents also received 12 sessions of ACT-based parent training, every 2 weeks. The outcome measure for the present study was the change in the cognitive performance assessed by a battery of computerised task. The cognitive outcome of children receiving ACT-group intervention was compared to that of an external untreated control group of children with ADHD. No significant improvements were observed in any of the cognitive measures. This preliminary study suggests that the 9-month ACT-group training programme might not have positive effects on cognitive difficulties usually occurring in ADHD. Future randomised controlled trials with larger sample sizes are required to shed more light on this issue.

Neuroethical issues in cognitive enhancement: Modafinil as the example of a workplace drug?

The use of cognitive-enhancing drugs by healthy individuals has been a feature for much of recorded history. Cocaine and amphetamine are modern cases of drugs initially enthusiastically acclaimed for enhancing cognition and mood. Today, an increasing number of healthy people are reported to use cognitive-enhancing drugs, as well as other interventions, such as non-invasive brain stimulation, to maintain or improve work performance. Cognitive-enhancing drugs, such as methylphenidate and modafinil, which were developed as treatments, are increasingly being used by healthy people. Modafinil not only affects ‘cold’ cognition, but also improves ‘hot’ cognition, such as emotion recognition and task-related motivation. The lifestyle use of ‘smart drugs’ raises both safety concerns as well as ethical issues, including coercion and increasing disparity in society. As a society, we need to consider which forms of cognitive enhancement (e.g. pharmacological, exercise, lifelong learning) are acceptable and for which groups under what conditions and by what methods we would wish to improve and flourish.

Brief and extended abstinence from chronic oral methylphenidate treatment produces reversible behavioral and physiological effects

Methylphenidate (MP) is a commonly prescribed psychostimulant to individuals with Attention Deficit Hyperactivity Disorder, and is often used illicitly among healthy individuals with intermittent breaks to coincide with breaks from school. This study examined how intermittent abstinence periods impact the physiological and behavioral effects of chronic oral MP self-administration in rats, and whether these effects persist following prolonged abstinence from the drug. Rats were treated orally with water, low-dose (LD), or high-dose (HD) MP, beginning at PND 28. This daily access continued for three consecutive weeks followed by a 1-week abstinence; after three repeats of this cycle, there was a 5-week abstinence period. Throughout the study, we examined body weight, food intake, locomotor activity, and anxiety- and depressive-like behaviors. During the treatment phase, HD MP decreased body weight, food intake, and depressive- and anxiety-like behaviors, while it increased locomotor activity. During intermittent abstinence, the effects of MP on locomotor activity were eliminated. During prolonged abstinence, most of the effects of HD MP were ameliorated to control levels, with the exception of weight loss and anxiolytic effects. These findings suggest that intermittent exposure to chronic MP causes physiological and behavioral effects that are mostly reversible following prolonged abstinence.

Auditory and Visual Executive Functions in Children and Response to Methylphenidate: A Randomized Controlled Trial

Objectives: The aim of the study was to assess auditory and visually based executive functions (EFs) and the effect of methylphenidate (MPH) in children with ADHD. Methods: Thirty-six boys between the ages of 8.3 and 9.7 years with ADHD and 36 matched controls were included. The study group was randomized into MPH and placebo for 7 days each in a crossover design. A Cued Choice Reaction Time (CCRT) test that included incongruent cuing was administered at baseline and following 1 and 2 weeks. Results: The difference between the study and control groups was more evident with visual cues and incongruent cuing. Increased gains by children with predominantly hyperactive-impulsive\combined (HI\C) type of ADHD were observed under MPH. Conclusions: The differences between children with ADHD and typical children are more pronounce under incongruent auditory cuing . The gains attributable to MPH are more specific to tasks involving auditory and visual EFs and in children with HI\C type ADHDs.

Physical exercise in attention deficit hyperactivity disorder - evidence and implications for the treatment of borderline personality disorder

A growing body of literature indicates a potential role for physical exercise in the treatment of attention deficit hyperactivity disorder (ADHD). Suggested effects include the reduction of ADHD core symptoms as well as improvements in executive functions. In the current review, we provide a short overview on the neurophysiological mechanisms assumed to underlie the beneficial effects of exercise. Further, we review the current evidence from experimental studies regarding both acute exercise and long-term interventions in ADHD. While the positive effects observed after acute aerobic exercise are promising, very few well-designed long-term intervention studies have been conducted yet. Moreover, although exercise effects have not yet been studied in borderline personality disorder (BPD), in the end of this paper we derive hypotheses why exercise could also be beneficial for this patient population.

Mental disorders and intimate partner violence perpetrated by men towards women: A Swedish population-based longitudinal study

BACKGROUND

Intimate partner violence (IPV) against women is associated with a wide range of adverse outcomes. Although mental disorders have been linked to an increased risk of perpetrating IPV against women, the direction and magnitude of the association remain uncertain. In a longitudinal design, we examined the association between mental disorders and IPV perpetrated by men towards women in a population-based sample and used sibling comparisons to control for factors shared by siblings, such as genetic and early family environmental factors.

METHODS AND FINDINGS

Using Swedish nationwide registries, we identified men from 9 diagnostic groups over 1998-2013, with sample sizes ranging from 9,529 with autism to 88,182 with depressive disorder. We matched individuals by age and sex to general population controls (ranging from 186,017 to 1,719,318 controls), and calculated the hazard ratios of IPV against women. We also estimated the hazard ratios of IPV against women in unaffected full siblings (ranging from 4,818 to 37,885 individuals) compared with the population controls. Afterwards, we compared the hazard ratios for individuals with psychiatric diagnoses with those for siblings using the ratio of hazard ratios (RHR). In sensitivity analyses, we examined the contribution of previous IPV against women and common psychiatric comorbidities, substance use disorders and personality disorders. The average follow-up time across diagnoses ranged from 3.4 to 4.8 years. In comparison to general population controls, all psychiatric diagnoses studied except autism were associated with an increased risk of IPV against women in men, with hazard ratios ranging from 1.5 (95% CI 1.3-1.7) to 7.7 (7.2-8.3) (p-values < 0.001). In sibling analyses, we found that men with depressive disorder, anxiety disorder, alcohol use disorder, drug use disorder, attention deficit hyperactivity disorder, and personality disorders had a higher risk of IPV against women than their unaffected siblings, with RHR values ranging from 1.7 (1.3-2.1) to 4.4 (3.7-5.2) (p-values < 0.001). Sensitivity analyses showed higher risk of IPV against women in men when comorbid substance use disorders and personality disorders were present, compared to risk when these comorbidities were absent. In addition, increased IPV risk was also found in those without previous IPV against women. The absolute rates of IPV against women ranged from 0.1% to 2.1% across diagnoses over 3.4 to 4.8 years. Individuals with alcohol use disorders (1.7%, 1,406/82,731) and drug use disorders (2.1%, 1,216/57,901) had the highest rates. Our analyses were restricted to IPV leading to arrest, suggesting that the applicability of our results may be limited to more severe forms of IPV perpetration.

CONCLUSIONS

Our results indicate that most of the studied mental disorders are associated with an increased risk of perpetrating IPV towards women, and that substance use disorders, as principal or comorbid diagnoses, have the highest absolute and relative risks. The findings support the development of IPV risk identification and prevention services among men with substance use disorders as an approach to reduce the prevalence of IPV.

Therapeutic effects of methylphenidate for attention-deficit/hyperactivity disorder in children with borderline intellectual functioning or intellectual disability: A systematic review and meta-analysis

Attention-deficit/hyperactivity disorder (ADHD) frequently co-occurs with intellectual disability in children, and may further compromise learning. Methylphenidate is a first-line treatment for ADHD, however no previous meta-analysis has evaluated its overall efficacy for ADHD in children with comorbid intellectual disability (ID) or borderline intellectual functioning. The PubMed/MEDLINE, Cochrane CENTRAL and ScienceDirect databases were systematically searched from inception through 2018/7/15 for clinical studies that investigated the effects of methylphenidate in children with ADHD and ID. A random-effects model meta-analysis was used for data synthesis. Eight studies (average Jadad score = 2.5) enrolling 242 participants receiving methylphenidate and 181 participants receiving placebo were included. The meta-analysis showed that methylphenidate led to a significant improvement in ADHD symptoms relative to placebo (Hedges’ g = 0.878, p < 0.001). Meta-regression analysis pointed to an association between the dose of methylphenidate and overall improvement in ADHD severity (slope = 1.334, p < 0.001). Finally, there was no significant difference in drop-out rate [odds ratio (OR) = 1.679, p = 0.260] or rate of treatment discontinuation due to adverse events (OR = 4.815, p = 0.053) between subjects receiving methylphenidate and those taking placebos. Our study suggests that methylphenidate retains its efficacy in children with ADHD and borderline intellectual functioning or ID.

Executive Function and Attention Performance in Children with ADHD: Effects of Medication and Comparison with Typically Developing Children

The emerging literature reports that children with Attention-Deficit/Hyperactivity Disorder (ADHD) show deficits in executive functioning. To date, the combination of drug therapy with certain evidence-based non-medication interventions has been proven to be the most effective treatment for ADHD. There is a gap in the literature regarding comparing the executive functions (EF) of treatment naïve and medicated children with ADHD with both each other and typically developing children. Altogether, 50 treatment naïve and 50 medicated children with ADHD and 50 typically developing children between the ages of six and 12 were enrolled. The Mini International Neuropsychiatric Interview for Children and Adolescents (Mini Kid) and the Test of Attentional Performance for Children (KiTAP) measures were employed. Treatment naïve children with ADHD showed weaker performance on most executive function measures (12 out of 15) than either the medicated ADHD group or the controls. There were no significant differences between the medicated ADHD children and typically developing children in most KiTAP parameters (10 out of 15). Executive function impairments were observable in treatment naïve ADHD children, which draws attention to the importance of treating ADHD. Future studies should focus on the specific effects of stimulant medication on executive functions.

Dopamine-mediated immunomodulation affects choroid plexus function

Immune system alterations have been implicated in various dopamine-related disorders, such as schizophrenia, bipolar disorder, and attention-deficit/hyperactivity disorder (ADHD). How immunity might be influenced by dopaminergic dysfunction and impact on clinically-relevant behaviors is still uncertain. We performed a peripheral and cerebral immunophenotyping in mice bearing dopaminergic alteration produced by genetic liability (hypofunction of the dopamine transporter DAT) and psychostimulant (amphetamine) administration. We found that DAT hypofunction influences immune tolerance by increasing functional Tregs and adrenomedullin levels in the thymus and spleen, while reducing microglia activation and infiltration of brain monocyte-derived macrophages (mo-MΦ). Remarkably, both DAT hypofunction and amphetamine treatment are associated with a weaker activation of the choroid plexus (CP) gateway. Conversely, amphetamine reactivated the CP in the setting of DAT hypofunction, paralleling its paradoxical ADHD-relevant behavioral effects. These findings add new knowledge on dopaminergic immunopharmacology and support the immunomodulation of CP functionality as a promising therapeutic strategy for neurodevelopmental and psychiatric disorders.

Methylphenidate and atomoxetine normalise fronto-parietal underactivation during sustained attention in ADHD adolescents

Problems with sustained attention are a key clinical feature of Attention Deficit/Hyperactivity Disorder (ADHD) which also manifests in poor performance and abnormal fronto-striato-parietal activation during sustained attention. Methylphenidate and atomoxetine improve attention functions and upregulate abnormal fronto-cortical activation during executive function tasks in ADHD patients. Despite this, no functional Magnetic Resonance Imaging (fMRI) study has compared the effects of methylphenidate and atomoxetine on the neurofunctional substrates of sustained attention in ADHD. This randomised, double-blind, placebo-controlled, cross-over study investigated the comparative normalisation effects of methylphenidate and atomoxetine on fMRI correlates and performance in 14 ADHD adolescents relative to 27 age-matched healthy controls during a parametric sustained attention/vigilance task with progressively increasing load of sustained attention. ADHD patients were scanned three times under a single clinical dose of either methylphenidate, atomoxetine, or placebo in pseudo-randomised order. Healthy controls were scanned once and compared to patients under each drug condition to test for potential drug-normalisation effects. Relative to controls, ADHD boys under placebo were impaired in performance and had underactivation in predominantly right-hemispheric fronto-parietal, and striato-thalamic regions. Both drugs normalised all underactivations, while only methylphenidate improved performance deficits. Within patients, methylphenidate had a drug-specific effect of upregulating left ventrolateral prefrontal/superior temporal activation relative to placebo and atomoxetine, while both drugs increased activation of right middle/superior temporal cortex, posterior cingulate, and precuneus relative to placebo. The study shows shared normalisation effects of methylphenidate and atomoxetine on fronto-striato-thalamo-parietal dysfunction in ADHD during sustained attention but a drug-specific upregulation effects of methylphenidate on ventral fronto-temporal regions.