Neuropsychological endophenotypes in ADHD with and without epilepsy

Onset of Inattention and Hyperactivity in Children and Adolescents With Epilepsy 6 months After the Diagnosis

OBJECTIVE

Complete or major symptoms of ADHD are often present in epilepsy. This study evaluated inattention and hyperactivity symptoms over the first 6 months in newly diagnosed pediatric epilepsy without comorbid ADHD.

METHOD

Children and adolescents with newly diagnosed epilepsy were followed for 6 months after starting antiseizure medications. The Nisonger Child Behavior Rating Form (NCBRF), Adverse Event Profile (AEP), and the Revised Wechsler Intelligence Scale for Children were used.

RESULTS

There was a marked increase in attention difficulties while a moderate increase in hyperactivity levels. AEP scores, changes in non-verbal aspects of intelligence, levels of hyperactivity at the follow-up, and attention at baseline were significant predictors for inattention. In contrast, only levels of hyperactivity at the baseline and inattention at the follow-up were significant predictors for hyperactivity.

CONCLUSION

Significant inattention and hyperactivity levels originated 6 months after the diagnosis of epilepsy and starting antiseizure medication.

MICEmi: A method to identify cognitive endophenotypes of mental illnesses

BACKGROUND

Characterizing neurocognitive endophenotypes of mental illnesses (MIs) could be useful for identifying at-risk individuals, increasing early diagnosis, improving disease subtyping, and proposing therapeutic strategies to reduce the negative effects of the symptoms, in addition to serving as a scientific basis to unravel the physiopathology of the disease. However, a standardized algorithm to determine cognitive endophenotypes has not yet been developed. The main objective of this study was to present a method for the identification of endophenotypes in MI research.

METHODS

For this purpose, a 14-expert working group used a scoping review methodology and designed a method that includes a scoring template with five criteria and indicators, a strategy for their verification, and a decision tree.

CONCLUSIONS

This work is ongoing since it is necessary to obtain external validation of the applicability of the method in future research.

Interventions for ADHD in children & adolescents with epilepsy: A review and decision tree to guide clinicians

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common pediatric epilepsy comorbidities. Treating ADHD in the context of epilepsy can be overwhelming for parents and clinicians. Current frontline treatment for ADHD is stimulant medication. However, some parents of pediatric patients with epilepsy have concerns about adding additional medication to their child's epilepsy regimen and/or about adverse effects of stimulant medication. Non-medication ADHD treatments including psychosocial interventions and ketogenic diet have also shown success in improving ADHD symptoms. Our focused review provides an easy-to-use guide for clinicians on ADHD interventions and combinations of interventions for pediatric patients with epilepsy and ADHD. Our guide includes information from 8 electronic databases for peer-reviewed, English language studies of psychosocial treatments for youth with epilepsy and ADHD. One hundred eight studies were selected based on inclusion criteria (21 systematic reviews, 12 meta-analyses, 8 literature reviews, 6 population surveys, 31 clinical trials, 20 cross-sectional studies, and 10 retrospective reviews). Results indicated that stimulant medication is a frontline treatment for ADHD symptoms in youth with epilepsy, with important caveats and alternatives.

Working Memory in Pediatric Epilepsy: A Systematic Review and Meta-Analysis

Working memory is a multicomponent system that is supported by overlapping specialized networks in the brain. Baddeley's working memory model includes four components: the phonological loop, visuo-spatial sketchpad, the central executive, and episodic buffer. The aim of this review was to establish the gravity and pattern of working memory deficits in pediatric epilepsy. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guided electronic searches. Sixty-five studies were included in the review. Meta-analyses revealed significant impairments across each working memory component: phonological loop (g = 0.739), visuo-spatial sketchpad (g = 0.521), and central executive (g = 0.560) in children with epilepsy compared to controls. The episodic buffer was not examined. The pattern of impairments, however, differed according to the site and side of seizure focus. This suggests that working memory components are differentially vulnerable to the location of seizure focus in the developing brain.

Associating executive dysfunction with behavioral and socioemotional problems in children with epilepsy. A systematic review

As children with epilepsy may have a number of learning and behavioral problems, it is important that insight into the underlying neurocognitive differences in these children, which may underlie these areas of challenge is gained. Executive function (EF) problems particularly are associated with specific learning abilities as well as behavioral problems. We aim to review systematically the current status of empirical studies on the association between EF problems and behavior and socioemotional problems in children with epilepsy. After search, 26 empirical studies were identified, most of them of moderate quality. Overall, attention problems were the most reported cognitive deficit in test assessment and the most reported problem by parents. In 54% of the studies, children with epilepsy scored below average compared to controls/normative samples on different aspects of EF. Most studies reported behavior problems, which ranged from mild to severe. Forty-two percent of the studies specifically reported relationships between EF deficits and behavioral problems. In the remaining studies, below average neuropsychological functioning seemed to be accompanied by above average reported behavioral problems. The association was most pronounced for cognitive control and attention in relation to externalizing behavior problems. This cognitive control is also associated with social functioning. Relevant epilepsy variables in this relationship were early age at onset and high seizure frequency.Future research should distinguish specific aspects of EF and take age into account, as this provides more insight on the association between EF and behavior in pediatric epilepsy, which makes it possible to develop appropriate and early intervention.

Methylphenidate treatment for cognitive symptoms associated with ADHD in a pediatric epilepsy patient following resection of a left frontal cortical dysplasia

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ADHD symptoms can emerge or worsen after epilepsy surgery.

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Methylphenidate use improved cognitive symptoms of ADHD in our patient.

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Seizure aggravation did not occur following use of a neurostimulant in our patient.

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Our patient benefitted from a multidisciplinary intervention approach.

We present data on a 10-year-old patient with drug-resistant epilepsy who was treated with methylphenidate for symptoms of attention deficit hyperactivity disorder (ADHD) that developed after she underwent surgical resection of a left frontal cortical dysplasia. . The patient’s parents reported methylphenidate was helpful in improving their child’s reading performance. Based on parents’ report, we examined benefits of methylphenidate on our patient’s cognitive problems in a controlled setting. The patient underwent a neuropsychological evaluation completed in three sessions over a five-day period. Methylphenidate was administered prior to the second testing session only and was associated with improvements in the patient’s attention, executive function, processing speed, and short-term memory performances. In comparison, word-reading performance, a task less susceptible to neurological impairment, was stable over the three sessions. The patient remained seizure-free after surgery and use of methylphenidate did not reduce seizure threshold. These findings support the use of methylphenidate in treating targeted cognitive problems associated with ADHD emerging after epilepsy surgery in children.

The Oscillatory Basis of Working Memory Function and Dysfunction in Epilepsy

Working memory (WM) deficits are pervasive co-morbidities of epilepsy. Although the pathophysiological mechanisms underpinning these impairments remain elusive, it is thought that WM depends on oscillatory interactions within and between nodes of large-scale functional networks. These include the hippocampus and default mode network as well as the prefrontal cortex and frontoparietal central executive network. Here, we review the functional roles of neural oscillations in subserving WM and the putative mechanisms by which epilepsy disrupts normative activity, leading to aberrant oscillatory signatures. We highlight the particular role of interictal epileptic activity, including interictal epileptiform discharges and high frequency oscillations (HFOs) in WM deficits. We also discuss the translational opportunities presented by greater understanding of the oscillatory basis of WM function and dysfunction in epilepsy, including potential targets for neuromodulation.

The role of task-based neural activation research in understanding cognitive deficits in pediatric epilepsy

Children with epilepsy can experience significant cognitive dysfunction that can lead to academic underachievement. Traditionally believed to be primarily due to the effects of factors such as the chronicity of epilepsy, medication effects, or the location of the primary epileptogenic lesion;, recent evidence has indicated that disruption of cognition-specific distributed neural networks may play a significant role as well. Specifically, over the last decade, researchers have begun to characterize the mechanisms underlying disrupted cognitive substrates by evaluating neural network abnormalities observed during specific cognitive tasks, using task-based functional magnetic resonance imaging (fMRI). This targeted review assesses the current literature investigating the relationship between neural network abnormalities and cognitive deficits in pediatric epilepsy. The findings indicate that there are indeed neural network abnormalities associated with deficits in executive function, language, processing speed, and memory. Overall, cognitive dysfunction in pediatric epilepsy is associated with a decrease in neural network activation/deactivation as well as increased recruitment of brain regions not typically related to the specific cognitive task under investigation. The research to date has focused primarily on children with focal epilepsy syndromes with small sample sizes and differing research protocols. More extensive research in children with a wider representation of epilepsy syndromes (including generalized epilepsy syndromes) is necessary to fully understand these relationships and begin to identify underlying cognitive phenotypes that may account for the variability observed across children with epilepsy. Furthermore, more uniformity in fMRI protocols and neuropsychological tasks would be ideal to advance this literature.

Contribution of Family Relatedness to Neurobehavioral Comorbidities in Idiopathic Childhood Epilepsies

OBJECTIVES

Rates of cognitive, academic and behavioral comorbidities are elevated in children with epilepsy. The contribution of environmental and genetic influences to comorbidity risk is not fully understood. This study investigated children with epilepsy, their unaffected siblings, and controls to determine the presence and extent of risk associated with family relatedness across a range of epilepsy comorbidities.

METHODS

Participants were 346 children (8-18 years), n=180 with recent-onset epilepsy, their unaffected siblings (n=67), and healthy first-degree cousin controls (n=99). Assessments included: (1) Child Behavior Checklist/6-18 (CBCL), (2) Behavior Rating Inventory of Executive Function (BRIEF), (3) history of education and academic services, and (4) lifetime attention deficit hyperactivity disorder (ADHD) diagnosis. Analyses consisted of linear mixed effect models for continuous variables, and logistic mixed models for binary variables.

RESULTS

Differences were detected between the three groups of children across all measures (p<.001). For ADHD, academic problems, and executive dysfunction, children with epilepsy exhibited significantly more problems than unaffected siblings and controls; siblings and controls did not differ statistically significantly from each other. For social competence, children with epilepsy and their unaffected siblings displayed more abnormality compared with controls, with no statistically significant difference between children with epilepsy and unaffected siblings. For behavioral problems, children with epilepsy had more abnormality than siblings and controls, but unaffected siblings also exhibited more abnormalities than controls.

CONCLUSIONS

The contribution of epilepsy and family relatedness varies across specific neurobehavioral comorbidities. Family relatedness was not significantly associated with rates of ADHD, academic problems and executive dysfunction, but was associated with competence and behavioral problems. (JINS, 2018, 24, 653-661).

Maintenance effects of working memory intervention (Cogmed) in children with symptomatic epilepsy

PURPOSE

To extend previous research documenting the benefits of working memory (WM) intervention (Cogmed) immediately post-intervention in children with epilepsy by assessing the 3-month maintenance effects.

METHODS

Participants involved in a previous randomized clinical trial (RCT) were invited to participate if they completed Cogmed within the last 3months (n=15) and additional participants (n=13) were prospectively recruited. Standardized assessments of near-transfer effects (i.e., visual and auditory attention and WM) were completed prior to and immediately after intervention and at 3-month follow-up. An additional measure assessing the far-transfer effect of fluid reasoning was administered prior to intervention and at 3-month follow-up.

RESULTS

Participants exhibited gains in auditory and visual attention and WM immediately following intervention and gains were generally sustained at 3-month follow-up. Intervention did not improve visual-verbal WM or fluid reasoning. The clinical variables studied (i.e., age of seizure onset, seizure frequency, epilepsy duration, and overall intellectual functioning) did not elucidate reliable relationships with intervention.

CONCLUSIONS

Working memory training is possibly efficacious in improving related skills which are maintained for 3months in children with active epilepsy. No transfer to fluid reasoning was documented. Further investigation by means of a large-scale RCT which includes a placebo and both objective and subjective measures of the impact of training on daily functioning is warranted.

Near-transfer effects following working memory intervention (Cogmed) in children with symptomatic epilepsy: An open randomized clinical trial

OBJECTIVE

Limited research exists regarding the effectiveness of educational and psychological interventions for improving commonly presenting cognitive impairments experienced by children with epilepsy. We evaluated the efficacy of a commercially available, computerized, working memory (WM) program (Cogmed) using a well-defined population of children with epilepsy.

METHODS

In this controlled trial, 77 children with symptomatic epilepsy (ages 6.5-15.5 years; 100% taking medication) with estimated intellectual ability greater than the 2nd percentile were randomly assigned to an intervention (n = 42) or waitlist-control (n = 35) group. Standardized assessments of attention and WM were administered pre- and posttraining or waitlist interval, 7 weeks apart.

RESULTS

Without intervention, participants displayed significant weaknesses in intelligence, attention, and WM compared to normative samples. After controlling for preintervention scores and intelligence, we found that significant treatment effects for the intervention group were evident for visual attention span, auditory WM, and visual-verbal WM. Intention-to-treat analyses (all participants) and sensitivity analyses (n = 37 and n = 21 for the intervention and waitlist-control groups, respectively) were highly similar, providing confidence to the results. Effect sizes for significant outcomes were large (greater than or equal to two thirds of the standard deviation of the normative-data). The clinical/demographic and functional factors studied did not elucidate who most benefits from training.

SIGNIFICANCE

This is the first study to evaluate the effectiveness of intervention to ameliorate WM deficits commonly experienced by children with symptomatic epilepsy. Results support group improvement on some untrained tasks immediately postintervention, demonstrating preliminary usefulness of Cogmed as a treatment option.

Speed and complexity characterize attention problems in children with localization-related epilepsy

OBJECTIVE

Children with epilepsy (EPI) have a higher rate of attention-deficit/hyperactivity disorder (ADHD; 28-70%) than typically developing (TD) children (5-10%); however, attention is multidimensional. Thus, we aimed to characterize the profile of attention difficulties in children with epilepsy.

METHODS

Seventy-five children with localization-related epilepsy ages 6-16 years and 75 age-matched controls were evaluated using multimodal, multidimensional measures of attention including direct performance and parent ratings of attention as well as intelligence testing. We assessed group differences across attention measures, determined if parent rating predicted performance on attention measures, and examined if epilepsy characteristics were associated with attention skills.

RESULTS

The EPI group performed worse than the TD group on timed and complex attention aspects of attention (p < 0.05), whereas performance on simple visual and simple auditory attention tasks was comparable. Children with EPI were 12 times as likely as TD children to have clinically elevated symptoms of inattention as rated by parents, but ratings were a weak predictor of attention performance. Earlier age of onset was associated with slower motor speed (p < 0.01), but no other epilepsy-related clinical characteristics were associated with attention skills.

SIGNIFICANCE

This study clarifies the nature of the attention problems in pediatric epilepsy, which may be under-recognized. Children with EPI had difficulty with complex attention and rapid response, not simple attention. As such, they may not exhibit difficulty until later in primary school when demands increase. Parent report with standard ADHD screening tools may under-detect these higher-order attention difficulties. Thus, monitoring through direct neuropsychological performance is recommended.

Clinical and neuropsychological assessment of attention and ADHD comorbidity in a sample of children and adolescents with idiopathic epilepsy

Children with epilepsy present significant problems concerning attention and comorbidity with attention deficit hyperactivity disorder (ADHD). Objective To determine the prevalence of attention complaints, ADHD diagnosis and attention profile in a sample of children and adolescents with idiopathic epilepsy. Method 36 children and adolescents with idiopathic epilepsy and 37 genre and age matched healthy controls underwent several procedures to diagnose their neuropsychological profile and comorbidity with ADHD. Results The prevalence of ADHD was higher in patients with epilepsy [χ2= 4.1, p = 0.043, 6 (16.7%) vs 1 (2.7%)], with worse results in attention related WISC items and factors in patients with epilepsy comparing to the controls, but not between patients with and without ADHD. Clinical characteristics did not influence those results. Conclusion This study found a greater prevalence of problems wih attention in pediatric patients with idiopathic epilepsy, but not a distinct profile between those with or without ADHD.

Cognitive function in childhood epilepsy: importance of attention deficit hyperactivity disorder

Background and Purpose

To determine how cognitive function is related to epilepsy classification and comorbid attention deficit hyperactivity disorder (ADHD) in children with newly diagnosed epilepsy of genetic or unknown etiology.

Methods

The medical records of children aged 6-16 years with newly diagnosed epilepsy of genetic or unknown etiology were reviewed retrospectively. The Korean Education Development Institute-Wechsler Intelligence Scale for Children and the Comprehensive Attention Test were used to evaluate intelligence and attention/executive function, respectively.

Results

The data of a total of 149 children, 103 with focal seizures and 46 with generalized seizures, were reviewed. The prevalence of ADHD was 49.2% (59 out of 120 examined patients), and ADHD patients exhibited significantly worse auditory selective attention, flanker test results, and spatial working memory. Patients with generalized seizures exhibited significantly worse auditory selective and sustained attention than patients with focal seizures. In patients with generalized seizures, sustained attention, flanker test findings, and spatial working memory were found to be affected by ADHD, and auditory selective and sustained attention were significantly worse in patients with benign childhood epilepsy with centrotemporal spikes and ADHD than in their counterparts without ADHD.

Conclusions

Cognitive processes are affected by seizure type and comorbid ADHD. Proper characterization of these neuropsychiatric impairments may allow earlier intervention during the disease course.

Cognitive estimations as a measure of executive dysfunction in childhood epilepsy

Children and adolescents with epilepsy are known to demonstrate executive function deficits. Despite prior work that has shown that cognitive estimation tasks are sensitive to executive dysfunction in children, such tasks have not been studied in children with epilepsy. This is particularly important given the fact that executive tasks have heretofore shown poor ecological validity, and it has been speculated that estimation tasks may show stronger ecological validity than other executive tests. One hundred and thirteen clinically referred children and adolescents with epilepsy were included. The Biber Cognitive Estimations Test was sensitive to cognitive dysfunction, with about half showing impairments on this task in comparison to age-matched normative data; the most frequently impaired subscales were quantity estimation and time estimation. Moreover, the Biber Cognitive Estimation Test showed moderate correlations with not only overall intellectual functions and academic achievement but also other commonly administered tests of executive functions, including digit span, Trailmaking, and the Tower of London but not with the contingency naming test. Cognitive estimations were also modestly correlated with age of epilepsy onset but not other epilepsy-severity variables such as number of antiepilepsy drugs (AEDs) or seizure frequency. Unfortunately, the hypothesis that the Biber Cognitive Estimation Test would show strong ecological validity was not supported, as it showed weak relations with parent-reported executive function deficits. The significance and limitations of this investigation are discussed.

Investigating inhibitory control in children with epilepsy: an fMRI study

OBJECTIVE

Deficits in executive function are noted increasingly in children with epilepsy and have been associated with poor academic and psychosocial outcomes. Impaired inhibitory control contributes to executive dysfunction in children with epilepsy; however, its neuroanatomic basis has not yet been investigated. We used functional magnetic resonance imaging (fMRI) to probe the integrity of activation in brain regions underlying inhibitory control in children with epilepsy.

METHODS

This cross-sectional study consisted of 34 children aged 8-17 years: 17 with well-controlled epilepsy and 17 age- and sex-matched controls. Participants performed the antisaccade (AS) task, representative of inhibitory control, during fMRI scanning. We compared AS performance during neutral and reward task conditions and evaluated task-related blood oxygen level-dependent (BOLD) activation.

RESULTS

Children with epilepsy demonstrated impaired AS performance compared to controls during both neutral (nonreward) and reward trials, but exhibited significant task improvement during reward trials. Post hoc analysis revealed that younger patients made more errors than older patients and all controls. fMRI results showed preserved activation in task-relevant regions in patients and controls, with the exception of increased activation in the left posterior cingulate gyrus in patients specifically with generalized epilepsy across neutral and reward trials.

SIGNIFICANCE

Despite impaired inhibitory control, children with epilepsy accessed typical neural pathways as did their peers without epilepsy. Children with epilepsy showed improved behavioral performance in response to the reward condition, suggesting potential benefits of the use of incentives in cognitive remediation.