Multimodal treatment in children and adolescents with attention-deficit/hyperactivity disorder: a 6-month follow-up

Background: Different treatment approaches aimed at reducing attention-deficit/hyperactivity disorder (ADHD) core symptoms are available. However, factors such as intolerance, side-effects, lack of efficacy, high new technology costs, and placebo effect have spurred on an increasing interest in alternative or complementary treatment.

Aim: The aim of this study is to explore efficacy of multimodal treatment consisting of standard stimulant medication (methylphenidate) and neurofeedback (NF) in combination, and to compare it with the single treatment in 6-month follow-up in ADHD children and adolescents.

Methods: This randomized controlled trial with 6-month follow-up comprised three treatment arms: multimodal treatment (NF?+?MED), MED alone, and NF alone. A total of 130 ADHD children/adolescents participated, and 62% completed the study. ADHD core symptoms were recorded pre-/post-treatment, using parents’ and teachers’ forms taken from Barkley’s Defiant Children: A Clinician’s Manual for Assessment and Parent Training, and a self-report questionnaire.

Results: Significant ADHD core symptom improvements were reported 6 months after treatment completion by parents, teachers, and participants in all three groups, with marked improvement in inattention in all groups. However, no significant improvements in hyperactivity or academic performance were reported by teachers or self-reported by children/adolescents, respectively, in the three groups. Changes obtained with multimodal treatment at 6-month follow-up were comparable to those with single medication treatment, as reported by all participants.

Conclusions: Multimodal treatment using combined stimulant medication and NF showed 6-month efficacy in ADHD treatment. More research is needed to explore whether multimodal treatment is suitable for ADHD children and adolescents who showed a poor response to single medication treatment, and for those who want to reduce the use of stimulant medication.     

Effects of Neurofeedback Training on Inhibitory Capacities in ADHD Children: A Single-Blind,Randomized, Placebo-Controlled Study

Introduction. Studies performed during the last decades suggest that neurofeedback (NF) training can effectively reduce symptomatology in children with Attention deficit hyperactivity disorder (ADHD). Yet questions remain concerning specific effects of NF training in ADHD children, because these studies did not use a randomized, placebo-controlled approach. To address this issue, such an approach was used in the present study to measure the impact of NF training on inhibitory capacities.

Method. Nine ADHD children (with no comorbidity), aged 8 to 13 years, were randomly assigned to either an experimental group (n = 5) or a placebo group (n = 4). For both groups, training protocols comprised 40 one-hr sessions (20 meetings of 2 sessions each). Sensorimotor rhythm/Theta training was used in the experimental group. Prerecorded sessions of the first author's EEG activity were used in the placebo group. Pre- and posttraining assessments consisted of the Conner's Parent Rating Scales (CPRS–R) and neuropsychological tests. A multiple case study strategy was applied for data analysis using a Reliable Change Index when applicable.

Results. One experimental participant was a dropout, and one placebo participant had to be discontinued due to adverse effects. The latter participant accepted to undergo posttraining evaluations; hence an Intention-to-Treat analysis was performed on this participant's data. Remaining participants showed significant improvements on the CPRS–R. Improvements were measured on the Variability measure of the CPT–II consistently across the placebo group and on the Inhibition Condition of the Stroop Task for all but one placebo participant. The same trend was found for the Inhibition/Switching Condition (Stroop Task) across the experimental group (n = 4).

Conclusion. The small sample size precludes from evaluating specific neurofeedback effects. Still, the presence of placebo responses suggests that other factors, such as motivation or expectations, might contribute to the outcome of NF training in children with ADHD.     

Slow cortical potential neurofeedback in attention deficit hyperactivity disorder: is there neurophysiological evidence for specific effects?

This study compared changes in quantitative EEG (QEEG) and CNV (contingent negative variation) of children suffering from ADHD treated by SCP (slow cortical potential) neurofeedback (NF) with the effects of group therapy (GT) to separate specific from non-specific neurophysiological effects of NF. Twenty-six children (age: 11.1 ± 1.15 years) diagnosed as having ADHD were assigned to NF (N = 14) or GT (N = 12) training groups. QEEG measures at rest, CNV and behavioral ratings were acquired before and after the trainings and statistically analyzed. For children with ADHD-combined type in the NF group, treatment effects indicated a tendency toward improvement of selected QEEG markers. We could not find the expected improvement of CNV, but CNV reduction was less pronounced in good NF performers. QEEG changes were associated with some behavioral scales. Analyses of subgroups suggested specific influences of SCP training on brain functions. To conclude, SCP neurofeedback improves only selected attentional brain functions as measurable with QEEG at rest or CNV mapping. Effects of neurofeedback including the advantage of NF over GT seem mediated by both specific and non-specific factors. M. Doehnert and D. Brandeis have contributed equally to this paper.     

Neurofeedback Associated with Neurocognitive-Rehabilitation Training on Children with Attention-Deficit/Hyperactivity Disorder (ADHD)

Neurofeedback is a computer-based behavior training gaining increasing interest in the treatment of children with attention-deficit hyperactivity disorder (ADHD), but is not a complete therapy for these patients. To meet the need for a more integrative approach, this study used neurofeedback with cognitive rehabilitation therapy as a more comprehensive approach for children with ADHD. Thirty children (females) were selected randomly from visitors of 5 clinics in Tehran city. Subjects were placed into 2 experimental groups and 1 control group. Groups were matched based on age, gender and socioeconomic status. One experimental group solely received neurofeedback in 10 sessions, the other experimental group received neurofeedback with cognitive rehabilitation therapy, and the control group left therapy received no therapy or left in the initial stages of therapy. Integrated visual and auditory test (IVA) was used pre-test and post-test to measure attention and impulsivity in children with ADHD, in addition to Neurocognitive Joyful Attentive Training Intervention (NEJATI). Data was analyzed using dependent T-test and analysis of covariance (ANCOVA). There are meaningful differences between all groups in attention and impulsivity factors. The group who received neurofeedback with cognitive rehabilitation therapy showed more improvement in attention and impulsivity factors compared to the group who received only neurofeedback and the control group with no treatment. There was also a significant difference between the solely neurofeedback group and control group in the attention factor. Neurofeedback is a facilitator therapy to improve the attention factor in children with ADHD, but is not a complete therapy due to its lack of support in performance factors. A complementary therapy such as cognitive rehabilitation therapy that focuses more on performance factors would be a more effective therapy as it leads to more positive effects on impulsivity and hyperactivity.     

Neurofeedback in ADHD: a single-blind randomized controlled trial

Neurofeedback treatment has been demonstrated to reduce inattention, impulsivity and hyperactivity in children with attention deficit/hyperactivity disorder (ADHD). However, previous studies did not adequately control confounding variables or did not employ a randomized reinforcer-controlled design. This study addresses those methodological shortcomings by comparing the effects of the following two matched biofeedback training variants on the primary symptoms of ADHD: EEG neurofeedback (NF) aiming at theta/beta ratio reduction and EMG biofeedback (BF) aiming at forehead muscle relaxation. Thirty-five children with ADHD (26 boys, 9 girls; 6–14 years old) were randomly assigned to either the therapy group (NF; n = 18) or the control group (BF; n = 17). Treatment for both groups consisted of 30 sessions. Pre- and post-treatment assessment consisted of psychophysiological measures, behavioural rating scales completed by parents and teachers, as well as psychometric measures. Training effectively reduced theta/beta ratios and EMG levels in the NF and BF groups, respectively. Parents reported significant reductions in primary ADHD symptoms, and inattention improvements in the NF group were higher compared to the control intervention (BF, d _corr = −.94). NF training also improved attention and reaction times on the psychometric measures. The results indicate that NF effectively reduced inattention symptoms on parent rating scales and reaction time in neuropsychological tests. However, regarding hyperactivity and impulsivity symptoms, the results imply that non-specific factors, such as behavioural contingencies, self-efficacy, structured learning environment and feed-forward processes, may also contribute to the positive behavioural effects induced by neurofeedback training.     

A preliminary study of the different memory systems in neurofibromatosis type 1: What is impaired and what is spared?

BackgroundSince 1990's, the cognitive profile of children with a neurofibromatosis type 1 (NF1) has been refined by many different studies. Children with NF1 may exhibit a variety of cognitive dysfunctions. Memory difficulties have been reported, but the results are contradictory and, compared to other cognitive functions, memory has been less evaluated.ObjectiveThe aim of this study was to investigate the memory profile in NF1 with a particular population, children with NF1 without attention deficit hyperactivity disorder (ADHD).MethodsEighteen children with NF1 without ADHD and eighteen typically developing aged from 8 to 12.6 years were compared in terms of both their verbal and visual working memory, anterograde memory, and procedural perceptual-motor memory. We also assessed semantic and autobiographical memory.ResultsOur results indicate the existence of memory difficulties in children with NF1 without ADHD in verbal working and anterograde memory but not in terms of the visual domain. They also experienced difficulties recalling personal memories but these were improved by cueing. However, semantic memory and procedural perceptual-motor memory was preserved.ConclusionsThese results highlight a difference between memory systems in children with NF1 without ADHD and the importance to assess the different memory systems, the nature of information and the processes in long-term memory in NF1 population. However, our results raise questions about the possible links between these difficulties and the executive functions. The specifics of memory profile in children with NF1 must be taken into consideration in these children’s clinical follow-up, in order to understand their learning difficulties and to make adaptations to their care.     

Components of Attention in Children with Complex Partial Seizures With and Without ADHD

Summary: Purpose: To evaluate attentional difficulties in children with complex partial seizures, we reviewed the records of 12 children with complex partial seizures with attention deficient hyperactivity disorder (CPS/ADHD); 21 children with CPS without ADHD (CPS); 22 children with ADHD; and 15 control children.
Methods: Each child completed a computerized performance test (CPT), which evaluated sustained attention, inhibition of response, response time, and consistency of response. The ADHD groups also completed the CPT after a dose of methylphenidate.
Results: The results found poorest performance on the CPT by the CPS/ADHD group. Particular difficulty in attention was found for children with epilepsy regardless of the ADHD diagnosis. When methylphenidate was administered to the ADHD groups, both groups improved in performance on the CPT.
Conclusions: Epilepsy may predispose children to attention problems that can significantly interfere with learning. Similar improvement for children with CPS/ADHD was found with methylphenidate compared with baseline as for children with ADHD but without CPS.     

Real‐time fMRI neurofeedback in adolescents with attention deficit hyperactivity disorder

Attention Deficit Hyperactivity Disorder (ADHD) is associated with poor self‐control, underpinned by inferior fronto‐striatal deficits. Real‐time functional magnetic resonance neurofeedback (rtfMRI‐NF) allows participants to gain self‐control over dysregulated brain regions. Despite evidence for beneficial effects of electrophysiological‐NF on ADHD symptoms, no study has applied the spatially superior rtfMRI‐NF neurotherapy to ADHD. A randomized controlled trial tested the efficacy of rtfMRI‐NF of right inferior prefrontal cortex (rIFG), a key region that is compromised in ADHD and upregulated with psychostimulants, on improvement of ADHD symptoms, cognition, and inhibitory fMRI activation. To control for region‐specificity, an active control group received rtfMRI‐NF of the left parahippocampal gyrus (lPHG). Thirty‐one ADHD boys were randomly allocated and had to learn to upregulate their target brain region in an average of 11 rtfMRI‐NF runs over 2 weeks. Feedback was provided through a video‐clip of a rocket that had to be moved up into space. A transfer session without feedback tested learning retention as a proximal measure of transfer to everyday life. Both NF groups showed significant linear activation increases with increasing number of runs in their respective target regions and significant reduction in ADHD symptoms after neurotherapy and at 11‐month follow‐up. Only the group targeting rIFG, however, showed a transfer effect, which correlated with ADHD symptom reductions, improved at trend level in sustained attention, and showed increased IFG activation during an inhibitory fMRI task. This proof‐of‐concept study demonstrates for the first time feasibility, safety, and shorter‐ and longer‐term efficacy of rtfMRI‐NF of rIFG in adolescents with ADHD. Hum Brain Mapp 38:3190–3209, 2017. © 2017 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.     

Current Status of Neurofeedback for Attention-Deficit/Hyperactivity Disorder

As conventional treatments offer incomplete benefit for over 33?% of children with attention-deficit/hyperactivity disorder (ADHD) and many refuse to try them, additional treatments are needed. One of the most promising is neurofeedback (NF, EEG biofeedback), which trains the brain with real-time video/audio information about its electrical activity measured from scalp electrodes. Since 2010, data from 8 randomized controlled studies of NF have been published with overall mean effect sizes of: 0.40 (all measures), 0.42 (ADHD measures), 0.56 (inattention), and 0.54 (hyperactivity/ impulsivity). Unfortunately, the benefit reported from randomized studies has not been observed in the few small blinded studies conducted. Main study strengths include randomization, evidence-based diagnostic assessments, multi-domain treatment outcomes, use of some type of blinding, and sham control conditions. Main study limitations include lack of large samples, abnormal EEG participant selection, double-blinding, and testing of blind validity and sham inertness. Most recently, a collaborative NF research group has been planning a definitive double-blind well-controlled trial.     

Treatment of ADHD in neurofibromatosis type 1

Forty-six of 93 children with neurofibromatosis type 1 (NF1) were found to satisfy the diagnostic criteria for attention-deficit-hyperactivity disorder (ADHD). Detailed comparisons were made among 20 children with NF1 and ADHD (12 males, 8 females; mean age 10.7 years, SD 2.2), 26 control children with NF1 (15 males, 11 females; mean age 11.3 years, SD 2.3), 14 control children with ADHD (7 males; mean age 9.9 years, SD 1.9), and 14 normally developing control children (7 males; mean age 11.2 years, SD 2.8). Children with NF1 and ADHD had the lowest IQ scores among the four groups. Test of Variables of Attention (TOVA) scores were poorer in the NF1-ADHD and ADHD control groups than in the two non-ADHD groups. Those with NF1 and ADHD were rated significantly poorer on the Child Behavior Checklist (CBCL) than were the NF1 control group. By administrating low doses (5 to 15 mg) of methylphenidate to the NF1-ADHD group, significantly improved TOVA scores were obtained. One-year follow-up yielded significantly improved CBCL scores. Our results show a high incidence of ADHD in NF1 and support an association between ADHD and learning and social problems in children with NF1. It was demonstrated that stimulant medication can lead to improvement in cognitive, academic, and social problems of children with NF1 and ADHD.     

Neuropsychological assessment of ADHD subtypes

Starting from a discussion of the validity of neuropsychological methods for the diagnosis of ADHD the results of an own study are presented. What is the diagnostic value of the German version of the CPT (Continuous Performance Task) and the DAT (Dortmunder Aufmerksamkeitstest) in discriminating ADHD subtypes (according to DSM-IV) and in which areas do the children of each subtype differ from a control group of normal children? The computer versions of the CPT and DAT were administered to 14 boys with the "combined subtype" of ADHD, 14 boys with the "predominantly inattentive type" of ADHD and 18 boys without clinical signs; all groups were matched in age and intelligence. Subsequently the mean differences between the various test parameters were assessed as to their significance. Contrary to other studies there were no significant differences either between both ADHS types or relative to the control group with regard to the CPT omission errors and the reaction time. There were differences in the reaction variability both between the ADHD subtypes and relative to the control group. Only the "combined subtype", not the "pre-dominantly inattentive type" differed from the control group as to the CPT commission errors. Regarding the DAT, there were significant differences between all three groups regarding both the solution quality and the response delay.     

NEUROFEEDBACK TRAINING IN A CASE OF ATTENTION DEFICIT HYPERACTIVITY DISORDER

Abstract

Electroencephalographic biofeedback, also known as neurofeedback, has been used to improve attention in children with Attention Deficit Hyperactivity Disorder (ADHD). In the present case study, a ten-year-old boy completed 37 sessions of neurofeedback training over a six-month period on-site in a school setting. Beta brainwave training was applied for sessions 1 – 22 and replaced by sensorimotor rhythm training for sessions 23 – 37. A review of his national achievement test scores for four years revealed he improved performance the year he received neurofeedback and the gain was lost the year after treatment was completed. The participant had been receiving methylphenidate for the previous two years and remained on the medication throughout neurofeedback and for the year after neurofeedback treatment. Findings are suggestive of the advantages of incorporating neurofeedback training as part of a multimodal treatment program in a school setting for children with ADHD.     

Neurofeedback for children with ADHD: a comparison of SCP- and theta/beta-protocols

Research groups have consistently reported on behavioral and cognitive improvements of children with ADHD after neurofeedback. However, neurofeedback has not been commonly accepted as a treatment for ADHD. This is due, in part, to several methodological limitations. The neurofeedback literature is further complicated by having several different training protocols. Differences between the clinical efficacy of such protocols have not been examined. This study addresses previous methodological shortcomings while comparing the training of theta-beta-frequencies (theta-beta-group) with the training of slow cortical potentials (SCP-group). Each group comprised of 19 children with ADHD that were blind to group assignment. The training procedure consisted of 30 sessions and a six months follow-up training. Pre-/post measures at pretest, the end of the training and the follow-up included tests of attention, intelligence and behavioral variables. After having already reported intermediate data (Strehl et al. 2004), this paper gives account on final results: Both groups are able to voluntarily regulate cortical activity, with the extent of learned self-regulation depending on task and condition. Both groups improve in attention and IQ. Parents and teachers report significant behavioral and cognitive improvements. Clinical effects for both groups remain stable six months after training. Groups do not differ in behavioral or cognitive outcome variables.     

Differentiating attention deficits in children with fetal alcohol spectrum disorder or attention‐deficit–hyperactivity disorder

Aim The attention and inhibition problems found in children with attention‐deficit–hyperactivity disorder (ADHD) are also common in children with fetal alcohol spectrum disorders (FASDs). Attempts to distinguish ADHD from FASDs in terms of these deficits are rare and were pursued in this study. Method A total of 116 children (47 with ADHD, 31 males, 16 females; 30 with FASDs, 17 males, 13 females; and 39 comparison children, 20 males, 19 females) participated. The mean age was 9 years 4 months (SD 1y 8mo) in the ADHD groups, 8 years 10 months (SD 1y 2mo) in the FASD group, and 9 years 1 month (SD 1y 1mo) in the comparison group. Sustained attention was tested with a slow event rate continuous performance task (CPT). Inhibitory control was tested with both a slow and fast event rate Go/No‐Go task. Results On the CPT task, children with ADHD, combined type (ADHD‐C), ADHD, primarily inattentive type (ADHD‐PI), and FASDs showed greater declines in task performance as a function of time than comparison children, suggesting sustained attention problems in all clinical groups. Children’s Go/No‐Go performance was event‐rate dependent, with the ADHD‐C group being affected in the slow condition and the ADHD‐PI and FASD groups having problems with the fast condition. Interpretation Children with ADHD‐C are typically impaired in handling understimulation, while children with FASDs may have problems with overstimulation. The dissociation in responsivity to event rate between groups may have significant differential diagnostic value.     

ADHD and EEG-neurofeedback: a double-blind randomized placebo-controlled feasibility study

Electroencephalography (EEG)-neurofeedback has been shown to offer therapeutic benefits to patients with attention-deficit/hyperactivity disorder (ADHD) in several, mostly uncontrolled studies. This pilot study is designed to test the feasibility and safety of using a double-blind placebo feedback-controlled design and to explore the initial efficacy of individualized EEG-neurofeedback training in children with ADHD. Fourteen children (8–15 years) with ADHD defined according to the DSM-IV-TR criteria were randomly allocated to 30 sessions of EEG-neurofeedback (n = 8) or placebo feedback (n = 6). Safety measures (adverse events and sleep problems), ADHD symptoms and global improvement were monitored. With respect to feasibility, all children completed the study and attended all study visits and training sessions. No significant adverse effects or sleep problems were reported. Regarding the expectancy, 75% of children and their parent(s) in the active neurofeedback group and 50% of children and their parent(s) in the placebo feedback group thought they received placebo feedback training. Analyses revealed significant improvements of ADHD symptoms over time, but changes were similar for both groups. This pilot study shows that it is feasible to conduct a rigorous placebo-controlled trial to investigate the efficacy of neurofeedback training in children with ADHD. However, a double-blind design may not be feasible since using automatic adjusted reward thresholds may not work as effective as manually adjusted reward thresholds. Additionally, implementation of active learning strategies may be an important factor for the efficacy of EEG-neurofeedback training. Based on the results of this pilot study, changes are made in the design of the ongoing study.     

Neurofeedback for Adult Attention-Deficit/Hyperactivity Disorder: Investigation of Slow Cortical Potential Neurofeedback—Preliminary Results

Attention deficit/hyperactivity disorder (ADHD) is characterized by symptoms of inattention, impulsivity, and hyperactivity. Compared to ADHD in children, only a few studies have investigated ADHD in an adult population, and even less have investigated new forms of treatment such as neurofeedback. Neurofeedback has been applied effectively in various areas, especially in the treatment of children with ADHD, and symptom improvements were associated with increased amplitude of the contingent negative variation (CNV). This study investigated if any behavioral and electrophysiological changes reflected in the CNV can be observed after 15 sessions of SCP neurofeedback training. Furthermore, a comparison of CNV amplitude in adults with ADHD and a healthy control group was conducted. Continuous 22-channel EEG was acquired from 10 adults who met DSM–IV criteria for ADHD and 8 matched healthy controls. EEG recordings were collected pre/midtreatment and included resting EEG, P300, and CNV tasks as well as ADHD behavioral questionnaires. The adult ADHD group received 15 sessions of SCP training at Cz (referenced to A1, ground A2). The control group only underwent the EEG recording. After 15 sessions of SCP-training a significant improvement in self-ratings of ADHD symptoms was reported. In addition, a trend in increasing CNV mean amplitude was observed after training. A significant difference in baseline CNV between the adult ADHD group and the healthy control group was observed. These results give a promising outlook to the outcome after the completion of 30 sessions of SCP training. The differences in CNV amplitude between the ADHD group and healthy controls are in line with other studies about adult ADHD and CNV. This supports the idea of impaired self-regulation in adult ADHD. The behavioral improvements and increase in CNV after SCP training suggests that SCP training has a positive effect on adult ADHD symptoms and their origin.     

Differential measures of 'sustained attention' in children with attention-deficit/hyperactivity or tic disorders: relations to monoamine metabolism

Controversy exists on whether the constructs tested by paper/pencil and computerized continuous-performance tests (CPT) are similar, and the deficits recorded in children with attention-deficit/hyperactivity symptoms (ADHD) are comparable. Signal-detection measures were recorded on four such tests of 'sustained attention', with increasing working-memory requirements in healthy children (14; mean 10 years), and those with ADHD (14; mean 10 years) or a tic syndrome (TS, 11; mean 11 years). Clinical associations were sought from 24-h urinary measures of monoamine activity. The cancellation paper/pencil test revealed no group differences for errors or signal detection measures. On the CPT, ADHD children made more omission and commission errors than control subjects, but TS children made mostly omissions. This reflected the poor perceptual sensitivity (d-prime, d') for ADHD and conservative response criteria (beta) for TS children. This group difference extended to the CPTax, which was shown on a regression analysis to test for putative working-memory-related abilities as well as concentration. In all children, immediate response-feedback reduced omissions, and modestly improved d'. CPTax performance related negatively to dopamine metabolism in control subjects and to serotonin metabolism in the ADHD group. But comparisons between the metabolites in the ADHD group suggest that increased serotonin and decreased noradrenaline, with respect to dopamine metabolism, may detract from CPT performance in terms of d'. CPT tasks demonstrated a perceptual-based impairment in ADHD and response conservatism in TS patients independent of difficulty. Catecholamine activity was implicated in the promotion of perceptual processing in normal and ADHD children, but serotonin activity may contribute to poor CPTax (working-memory) performance in ADHD patients.     

Does attention‐deficit–hyperactivity disorder exacerbate executive dysfunction in children with neurofibromatosis type 1?

Aim Although approximately 40% of children with neurofibromatosis type 1 (NF1) meet diagnostic criteria for attention‐deficit–hyperactivity disorder (ADHD), the impact of ADHD on the executive functioning of children with NF1 is not understood. We investigated whether spatial working memory and response inhibition are impaired in children with NF1 without a diagnosis of ADHD and whether executive deficits are exacerbated in children with a comorbid diagnosis. Method Forty‐nine children aged 7 to 15 years with NF1 only (31 males, 18 females; mean age 11y, SD 2y 4mo) or 35 with NF1 and ADHD (18 males, 17 females; mean age 10y 8mo, SD 2y 4mo) and 30 typically developing comparison children (16 males, 14 females; mean age 10y, SD 2y 8mo) were compared on measures of spatial working memory and response inhibition. Group differences in IQ and visuospatial ability were controlled for as required. Results Compared with typically developing children, children with NF1 with or without comorbid ADHD demonstrated significant impairment of both spatial working memory (both p<0.004) and inhibitory control (both p<0.010). There were, however, no differences between the two NF1 groups in spatial working memory (p=0.91) or response inhibition (p=0.78). Interpretation Executive dysfunction occurs with the same severity in children with NF1, whether or not they have a comorbid diagnosis of ADHD, suggesting that executive impairments are not unique contributors to ADHD symptomatology in NF1. The findings are discussed within the context of recent evidence in Nf1 optic glioma (OPG) mice, in which a mechanistic connection between NF1 gene expression, executive system failure, and dopaminergic pathway integrity has been established.     

Age and medication effects on rhythmic responses in ADHD: possible oscillatory mechanisms?

Voluntary motor responses in children with attention-deficit hyperactivity disorder (ADHD) may reflect underlying neuronal oscillatory mechanisms. The aims of this study were: (1) to corroborate the presence of rhythmic motor abnormalities on tapping test in children with attention-deficit hyperactivity disorder, shown in previous studies; (2) to delineate the characteristics of ADHD children demonstrating these rhythmic abnormalities; (3) to assess the impact of methylphenidate (Ritalin) on this abnormal motor phenomenon. The study was designed in a double blind manner. Sixty-four ADHD children aged 6-12 years and 60 matched controls underwent a finger tapping test (1-5 Hz). We measured the abnormal rhythmic tapping with and without methylphenidate treatment in a double blind design. Conventional statistical analysis was used to assess the correlation of the presence of motor abnormality with various clinical characteristics (such as degree of hyperactivity/impulsivity). Fifty-six percent of children with ADHD compared to 8% of controls demonstrated abnormal rhythmic responses at a mean frequency of 3.1+/-0.9 Hz. These erroneous voluntary movements were more common in children with a greater degree of hyperactivity, in younger children but not significantly altered by methylphenidate treatment. Surprisingly, abnormal rhythmic responses showed less variability than found for responses for which the tapping was adequately paced, suggesting different motor control processes for normal and abnormal paced tapping. We speculate that rhythmic tapping responses reflect abnormal oscillatory mechanisms involved in ADHD, exacerbated in younger children with ADHD and in those in whom the hyperactivity/impulsivity is more pronounced.     

Clinical Utility of EEG in Attention-Deficit/Hyperactivity Disorder: A Research Update

Psychiatric research applications of electroencephalography (EEG), the earliest approach to imaging human cortical brain activity, are attracting increasing scientific and clinical interest. For more than 40 years, EEG research has attempted to characterize and quantify the neurophysiology of attention-deficit/hyperactivity disorder (ADHD), most consistently associating it with increased frontocentral theta band activity and increased theta to beta (θ/β) power ratio during rest compared to non-ADHD controls. Recent reports suggest that while these EEG measures demonstrate strong discriminant validity for ADHD, significant EEG heterogeneity also exists across ADHD-diagnosed individuals. In particular, additional studies validating the use of the θ/β power ratio measure appear to be needed before it can be used for clinical diagnosis. In recent years, the number and the scientific quality of research reports on EEG-based neurofeedback (NF) for ADHD have grown considerably, although the studies reviewed here do not yet support NF training as a first-line, stand-alone treatment modality. In particular, more research is needed comparing NF to placebo control and other effective treatments for ADHD. Currently, after a long period of relative stasis, the neurophysiological specificity of measures used in EEG research is rapidly increasing. It is likely, therefore, that new EEG studies of ADHD using higher density recordings and new measures drawn from viewing EEG as a 3-dimensional functional imaging modality, as well as intensive re-analyses of existing EEG study data, can better characterize the neurophysiological differences between and within ADHD and non-ADHD subjects, and lead to more precise diagnostic measures and effective NF approaches.