Neurocognitive profiles in children with epilepsy

Long-term forgetting is independent of age in healthy children and adolescents

Introduction

In clinical neuropsychology, the phenomenon of accelerated long-term forgetting (ALF) has advanced to be a marker for subtle but clinically relevant memory problems associated with a range of neurological conditions. The normal developmental trajectory of long-term memory, in this case, memory recall after 1 week, and the influence of cognitive variables such as intelligence have not extensively been described, which is a drawback for the use of accelerated long-term forgetting measures in pediatric neuropsychology.

Methods

In this clinical observation study, we analyzed the normal developmental trajectory of verbal memory recall after 1 week in healthy children and adolescents. We hypothesized that 1-week recall and 1-week forgetting would be age-dependent and correlate with other cognitive functions such as intelligence and working memory. Sixty-three healthy participants between the ages of 8 and 16 years completed a newly developed auditory verbal learning test (WoMBAT) and the WISC-V intelligence test (General Ability Index, GAI). Using these tests, 1 week recall and 1 week forgetting have been studied in relation to GAI, verbal learning performance, and verbal working memory.

Results

Neither 1-week recall nor 1-week forgetting seems to be age-dependent. They are also not significantly predicted by other cognitive functions such as GAI or working memory. Instead, the ability to recall a previously memorized word list after 7 days seems to depend solely on the initial learning capacity.

Conclusion

In the clinical setting, this finding can help interpret difficulties in free recall after 7 days or more since they can probably not be attributed to young age or low intelligence.

Attention deficit hyperactivity disorder in children with epilepsy: a multicenter cross-sectional analysis in China

BACKGROUND

The diagnosis and treatment of attention deficit hyperactivity disorder (ADHD) comorbid with epilepsy have been insufficiently addressed in China. We conducted a study in China to investigate the current status, diagnosis, and treatment of ADHD in children to further our understanding of ADHD comorbid with epilepsy, strengthen its management, and improve patients' quality of life.

METHODS

We carried out a multicenter cross-sectional survey of children with epilepsy across China between March 2022 and August 2022. We screened all patients for ADHD and compared various demographic and clinical factors between children with and without ADHD, including gender, age, age at epilepsy onset, duration of epilepsy, seizure types, seizure frequency, presence of epileptiform discharges, and treatment status. Our objective was to explore any possible associations between these characteristics and the prevalence of ADHD.

RESULTS

Overall, 395 epilepsy patients aged 6-18 years were enrolled. The age at seizure onset and duration of epilepsy ranged from 0.1-18 to 0.5-15 years, respectively. Focal onset seizures were observed in 212 (53.6%) patients, while 293 (76.3%) patients had epileptiform interictal electroencephalogram (EEG) abnormalities. Among the 370 patients treated with anti-seizure medications, 200 (54.1%) had monotherapy. Although 189 (47.8%) patients had ADHD, only 31 received treatment for it, with the inattentive subtype being the most common. ADHD was more common in children undergoing polytherapy compared to those on monotherapy. Additionally, poor seizure control and the presence of epileptiform interictal EEG abnormalities may be associated with a higher prevalence of ADHD.

CONCLUSIONS

While the prevalence of ADHD was higher in children with epilepsy than in normal children, the treatment rate was notably low. This highlights the need to give more importance to the diagnosis and treatment of ADHD in children with epilepsy.

Frequency of epilepsy and pathological EEG findings in a Norwegian sample of children with fetal alcohol spectrum disorder: Impact on cognition and adaptive functioning

BACKGROUND

Fetal alcohol spectrum disorder (FASD) comprises a combination of developmental, cognitive, and behavioral disabilities that occur in children exposed to alcohol prenatally. A higher prevalence of epilepsy and pathological electroencephalographic (EEG) features have also been reported in individuals with FASD. We examined the frequency of epilepsy, pathological EEG findings, and their implications for cognitive and adaptive functioning in children with FASD.

METHODS

We conducted a cross-sectional study of 148 children with FASD who underwent a multidisciplinary assessment and a 120-min EEG recording. Group comparisons and regression analyses were performed to test the associations between epilepsy and pathological EEG findings, FASD subgroups and neurocognitive test results and adaptive functioning.

RESULTS

The frequency of epilepsy was 6%, which compares with 0.7% in Norway overall. Seventeen percent of children without epilepsy had pathological EEG findings. Attention-deficit hyperactivity disorder (ADHD) was diagnosed in 64% of the children. Children with epilepsy and/or pathological EEG findings had comparable cognitive and adaptive scores to those with normal EEG. However, children with frontal EEG pathology (without epilepsy) had significantly lower scores on the IQ indices Processing speed and Working memory than FASD children without such findings, irrespective of ADHD comorbidity.

CONCLUSIONS

There was a greater prevalence of epilepsy among children with FASD than in the general Norwegian population. A greater frequency of EEG pathology was also evident in children without epilepsy, across all FASD subgroups. Irrespective of epilepsy, ADHD comorbidity, and FASD subgroup, children with frontal EEG pathology, despite having a normal total IQ, showed significantly slower processing speed and poorer working memory, which may indicate specific executive function deficits that could affect learning and adaptive functioning.

Neurocognitive profile in patients with idiopathic generalized epilepsies: Differences between patients, their biological siblings, and healthy controls

BACKGROUND

Idiopathic generalized epilepsy (IGE) is one of the most common epilepsies and is believed to have a strong genetic origin. Patients with IGE present largely heterogeneous neurocognitive profiles and might show some neurocognitive impairments. Furthermore, IGE siblings may demonstrate worse results in neuropsychological tests as well. In our study, we aimed to map the neurocognitive profile both in patients with IGE and the siblings. We also sought to establish a neurocognitive profile for each IGE syndrome.

METHODS

The research sample included 110 subjects (IGE n = 46, biological siblings BS n = 16, and healthy controls n = 48) examined. Subjects were neuropsychologically examined in domains of intelligence, attention, memory, executive, and motor functions. The data obtained from the examination were statistically processed to determine whether and how IGE patients (including distinct syndromes) and the siblings differed neurocognitively from healthy controls (adjusted z-scores by age, education, and gender, and composite z-scores of cognitive domains). Data on anti-seizure medication, including defined daily doses, were obtained and included in the analysis.

RESULTS

IGE patients and their biological siblings performed significantly worse in most of the neuropsychological tests than healthy controls. The neurocognitive profile of composite z-scores showed that IGE and biological siblings had equally significantly impaired performance in executive functions. IGE group also demonstrated impaired composite attention and motor function scores. The profile of individual IGE syndromes showed that JAE, JME, and EGTCS had significantly worse performance in composite execution score and motor function score. JAE presented significantly worse performance in intelligence and attention. JME exhibited significantly worse composite score in the attention domain. Anti-seizure medication, depression, and quality of life were unrelated to cognitive performance in IGE group. The level of depression significantly predicted the overall value of quality of life in patients with IGE, while cognitive domains, sociodemographic, and clinical factors were unrelated.

CONCLUSION

Our study highlights the importance to consider the neurocognitive profile of IGE patients that can lead to difficulties in their education, acceptance, and management of coping strategies. Cognitive difficulties of IGE siblings could support a hypothesis that these impairments emerge from heritable traits.

Epilepsy and Attention Deficit Hyperactivity Disorder: Connection, Chance, and Challenges

Comorbidities are common in children with epilepsy, with nearly half of the patients having at least one comorbidity. Attention deficit hyperactivity disorder (ADHD) is a psychiatric disorder characterized by hyperactivity and inattentiveness level disproportional to the child’s developmental stage. The burden of ADHD in children with epilepsy is high and can adversely affect the patients’ clinical outcomes, psychosocial aspects, and quality of life. Several hypotheses were proposed to explain the high burden of ADHD in childhood epilepsy; the well-established bidirectional connection and shared genetic/non-genetic factors between epilepsy and comorbid ADHD largely rule out the possibility of a chance in this association. Stimulants are effective in children with comorbid ADHD, and the current body of evidence supports their safety within the approved dose. Nonetheless, safety data should be further studied in randomized, double-blinded, placebo-controlled trials. Comorbid ADHD is still under-recognized in clinical practice. Early identification and management of comorbid ADHD are crucial to optimize the prognosis and reduce the risk of adverse long-term neurodevelopmental outcomes. The identification of the shared genetic background of epilepsy and ADHD can open the gate for tailoring treatment options for these patients through precision medicine.

Neuropsychological and behavioral profiles of self-limited epileptic syndromes of childhood: a cross-syndrome comparison

Childhood epilepsy with centro-temporal spikes (CECTS), Childhood absence epilepsy (CAE) and Panayiotopoulos syndrome (PS) are some of the most common pediatric epileptic syndromes. Despite the relatively benign (self-limited) course of epilepsy, current evidence suggests that these conditions are associated with an increased risk of neuropsychological and behavioral comorbidities. This study provides a cross-epileptic syndromes' comparison reporting on the cognitive and behavioral profile of a cohort of 32 children with CECTS (n = 14), CAE (n = 10) and PS (n = 8), aged 6 to 15 years old. Frequent, although often subclinical cognitive difficulties involving attention, executive functions and academic abilities were found in children with CECTS and CAE, and to a lesser extent in PS. Internalizing symptoms (particularly anxiety) were more common in the PS group compared to CECTS and CAE based on parental reports. Correlational analysis revealed a significant correlation between phonemic fluency and seizure-free interval at the time of evaluation, suggesting a beneficial effect of epilepsy remission on this executive function measure in all the three groups. These results add to existing literature providing further detail on neuropsychological and behavioral peculiarities of children with CECTS, CAE, and PS. Moreover, the need for neuropsychological assessment as part of the standard childhood epilepsy evaluation is stressed. The results are discussed in the context of the current literature, highlighting areas of consensus and controversies related to the clinical management of these epileptic syndromes as well as directions for future research.

Spectral changes following resective epilepsy surgery and neurocognitive function in children with epilepsy

Decelerated resting cortical oscillations, high-frequency activity, and enhanced cross-frequency interactions are features of focal epilepsy. The association between electrophysiological signal properties and neurocognitive function, particularly following resective surgery, is, however, unclear. In the current report, we studied intraoperative recordings from intracranial electrodes implanted in seven children with focal epilepsy and analyzed the spectral dynamics both before and after surgical resection of the hypothesized seizure focus. The associations between electrophysiological spectral signatures and each child's neurocognitive profiles were characterized using a partial least squares analysis. We find that extent of spectral alteration at the periphery of surgical resection, as indexed by slowed resting frequency and its acceleration following surgery, is associated with baseline cognitive deficits in children. The current report provides evidence supporting the relationship between altered spectral properties in focal epilepsy and neuropsychological deficits in children. In particular, these findings suggest a critical role of disrupted thalamocortical rhythms, which are believed to underlie the spectral alterations we describe, in both epileptogenicity and neurocognitive function.NEW & NOTEWORTHY Spectral alterations marked by decelerated resting oscillations and ectopic high-frequency activity have been noted in focal epilepsy. We leveraged intraoperative recordings from chronically implanted electrodes pre- and postresection to understand the association between these electrophysiological phenomena and neuropsychological function. We find that the extent of spectral alteration, indexed by slowed resting frequency and its acceleration following resection, is associated with baseline cognitive deficits. These findings provide novel insights into neurocognitive impairments in focal epilepsy.

Alterations in white matter integrity and asymmetry in patients with benign childhood epilepsy with centrotemporal spikes and childhood absence epilepsy: An automated fiber quantification tractography study

PURPOSE

To investigate whether patients with benign childhood epilepsy with centrotemporal spikes (BECTS) and childhood absence epilepsy (CAE) show distinct patterns of white matter (WM) alterations and structural asymmetry compared with healthy controls and the relationship between WM alterations and epilepsy-related clinical variables.

METHODS

We used automated fiber quantification to create tract profiles of fractional anisotropy (FA) and mean diffusivity (MD) in twenty-six patients with BECTS, twenty-nine patients with CAE, and twenty-four healthy controls. Group differences in FA and MD were quantified at 100 equidistant nodes along the fiber tract and these alterations and epilepsy-related clinical variables were correlated. A lateralization index (LI) representing the structural asymmetry of the fiber tract was computed and compared between both patient groups and controls.

RESULTS

Compared with healthy controls, the BECTS group showed widespread FA reduction in 43.75% (7/16) and MD elevation in 50% (8/16) of identified fiber tracts, and the CAE group showed regional FA reduction in 31.25% (5/16) and MD elevation in 25% (4/16) of identified fiber tracts. In the BECTS group, FA and MD in the right anterior thalamic radiation positively and negatively correlated with the number of antiepileptic drugs, respectively, and MD in the right arcuate fasciculus (AF) positively correlated with seizure frequency. In the CAE group, the LI values were significantly lower in the inferior fronto-occipital fasciculus and the AF.

CONCLUSION

The two childhood epilepsy syndromes display different patterns of WM alterations and structural asymmetry, suggesting that neuroanatomical differences may underlie the different profiles of BECTS and CAE.

The neural basis of executive functioning deficits in adolescents with epilepsy: a resting-state fMRI connectivity study of working memory

Working memory deficits are common in youth with epilepsy and consistently associated with long-term negative outcomes. Existing research on the neural basis of working memory disruptions in pediatric epilepsy is limited. The question of whether differences in the functional connectivity of neural networks underlie working memory disruptions in pediatric patients with epilepsy remains unanswered. A total of 49 adolescents between the ages of 13-17 years participated in this study. Twenty-nine adolescents had confirmed epilepsy (n = 17 generalized epilepsy, n = 6 localization-related, n = 6 unclassified). The control group included 20 healthy adolescents. A total of 10-min resting state functional magnetic resonance imaging was obtained for all participants. NeuroSynth-derived regions of interest were used as nodes that comprise working memory neural networks. Group differences in resting state functional connectivity were examined between adolescents with epilepsy and controls. Functional connectivity was computed as the temporal correlation of functional magnetic resonance imaging signal fluctuations between any two regions of interest. Compared to controls, adolescents in the epilepsy group demonstrated both hypoconnectivity and hyperconnectivity in cortical areas that map onto fronto-parietal and cingulo-opercular networks, as well as cerebellar regions. Functional connectivity between pairs of regions of interest was also significantly associated with behavioral measures of working memory across epilepsy and control groups. This study demonstrates that the presence of abnormal patterns in resting state neural network connectivity may underlie the working memory disruptions that frequently characterize the neurocognitive profile of youth with epilepsy.

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.

Altered functional network connectivity and working memory dysfunction in adolescents with epilepsy

Adolescents with epilepsy are at risk for deficits in working memory, which could lead to learning difficulties and poor academic outcomes. We used task-based functional magnetic resonance imaging (fMRI) to examine potential disruption in working memory function in adolescents with epilepsy as compared to healthy controls. We recruited 29 adolescents (13-17 years) with non-lesional epilepsy and 20 healthy controls. All participants performed an N-back fMRI task and neuropsychological testing. A general linear model approach was used to create group activation maps of N-back fMRI for epilepsy and control groups and both groups combined (p < 0.05 corrected for multiple comparisons). Functionally defined regions of interest (ROIs) were identified based on clusters of combined group activation (z > 5). Subsets of these functional ROIs corresponding to cingulo-opercular and fronto-parietal networks were selected and differences in functional connectivity between the epilepsy and control groups were assessed. Adolescents with epilepsy had significantly poorer working memory scores compared to controls. For the N-back fMRI task, there were no significant differences in group activation. Functional connectivity was significantly reduced between the left frontal operculum and anterior cingulate gyrus (cingulo-opercular network) in adolescents with epilepsy compared to controls. This study demonstrates working memory deficits and an altered pattern of connectivity in brain networks supporting working memory in adolescents with epilepsy. Working memory performance was worse in adolescents with epilepsy; though scores were not directly correlated with reduced connectivity. These results suggest the neural substrates of working memory in adolescents with epilepsy may differ from those in typically-developing adolescents, and require further investigation to understand the reasons for poorer working memory performance.

Absence epilepsy: Characteristics, pathophysiology, attention impairments, and the related risk of accidents. A narrative review

OBJECTIVE

Absence epilepsy (AE) is related to both cognitive and physical impairments. In this narrative review, we critically discuss the pathophysiology of AE and the impairment of attention in children and adolescents with AE. In particular, we contextualize the attentive dysfunctions of AE with the associated risks, such as accidental injuries.

DATA SOURCE

An extensive literature search on attention deficits and the rate of accidental injuries in AE was run. The search was conducted on Scopus, Pubmed, and the online libraries of the University of Twente and Maastricht University. Relevant references of the included articles were added. Retrospective and prospective studies, case reports, meta-analysis, and narrative reviews were included. Only studies written in English were considered. Date of last search is February 2020. The keywords used were "absence epilepsy" AND "attention"/"awareness", "absence epilepsy" AND "accidental injuries"/"accident*"/"injuries".

RESULTS

Ten retrospective and two prospective studies on cognition and AE were fully screened. Seventeen papers explicitly referring to attention in AE were reviewed. Just one paper was found to specifically focus on accidental injuries and AE, while twelve studies generally referring to epilepsy syndromes - among which AE - and related accidents were included.

CONCLUSION

Absence epilepsy and attention deficits show some patterns of pathophysiological association. This relation may account for dysfunctions in everyday activities in the pediatric population. Particular metrics, such as the risk related to biking in children with AE, should be used in future studies to address the problem in a novel way and to impact clinical indications.

Epilepsy and school in the Middle East and North Africa (MENA) region: The current situation, challenges, and solutions

Education is a human right that plays a key role in social and economic development. Children having active epilepsy may not be properly schooled in ordinary school structures. Students with epilepsy (SWE) are often faced with academic barriers. The lack of information about the current status of special education for SWE obliged the researchers to try to describe the existing reality of the special education practices in the Middle East and North Africa (MENA) region. We disseminated a simple self-administered questionnaire via email to main healthcare professionals involved in epilepsy care in the MENA region, and we also did a literature search on the PubMed, Google Scholar, and Embase engines. We ranked the countries in terms of their educational system. The 1st group contains the most advanced educational system, including specialized schools for SWE. The 2nd group contains an educational system with specialized but less structured schools. The 3rd group includes countries using integrated classes or classes mixing many children with cognitive disabilities. The 4th group includes countries with ordinary classes for SWE, and finally, the 5th group with no schooling for children with epilepsy (CWE). This study indicates that 60% of the countries in the MENA region belong to the 3rd group; there is only one country in each of the first two groups. This work highlights the need to develop structured environments for schooling for SWE in the MENA region.

Verbal memory in children with temporal lobe epilepsy: Exploring task-specificity

RATIONALE

This study explored the applicability of the adult model of task-specificity of memory to children with temporal lobe epilepsy (TLE).

METHOD

Retrospective clinical audit; 38 children and adolescents (6-16 years) with lesional TLE (n = 22 mesial; n = 16 lateral) treated at tertiary pediatric hospitals completed two types of verbal memory paradigms: arbitrary associative (Verbal Paired Associates - Hard Pairs) and semantically related (Verbal Paired Associates - Easy Pairs; Stories).

RESULTS

Children with mesial TLE performed more poorly than their lateral TLE counterparts on both types of memory paradigms: arbitrary associative and semantically related (Stories only). Groups with left and right TLE performed comparably on all verbal memory measures.

CONCLUSIONS

Our findings suggest that the adult model of task-specificity may not be completely applicable to children with TLE. Consideration of the developmental context is critical in research and clinical work with pediatric populations.

Psychosocial assessment of families caring for a child with acute lymphoblastic leukemia, epilepsy or asthma: Psychosocial risk as network of interacting symptoms

The purpose of this study is to assess psychosocial risk across several pediatric medical conditions and test the hypothesis that different severe or chronic pediatric illnesses are characterized by disease specific enhanced psychosocial risk and that risk is driven by disease specific connectivity and interdependencies among various domains of psychosocial function using the Psychosocial Assessment Tool (PAT). In a multicenter prospective cohort study of 195 patients, aged 5–12, 90 diagnosed with acute lymphoblastic leukemia (ALL), 42 with epilepsy and 63 with asthma, parents completed the PAT2.0 or the PAT2.0 generic version. Multivariate analysis was performed with disease as factor and age as covariate. Graph theory and network analysis was employed to study the connectivity and interdependencies among subscales of the PAT while data-driven cluster analysis was used to test whether common patterns of risk exist among the various diseases. Using a network modelling approach analysis, we observed unique patterns of interconnected domains of psychosocial factors. Each pathology was characterized by different interdependencies among the most central and most connected domains. Furthermore, data-driven cluster analysis resulted in two clusters: patients with ALL (89%) mostly belonged to cluster 1, while patients with epilepsy and asthma belonged primarily to cluster 2 (83% and 82% respectively). In sum, implementing a network approach improves our comprehension concerning the character of the problems central to the development of psychosocial difficulties. Therapy directed at problems related to the most central domain(s) constitutes the more rational one because such an approach will inevitably carry over to other domains that depend on the more central function.

Cognitive Function in Genetic Generalized Epilepsies: Insights From Neuropsychology and Neuroimaging

Genetic generalized epilepsies (GGE), previously called idiopathic generalized epilepsies, constitute about 20% of all epilepsies, and include childhood absence epilepsy, juvenile absence epilepsy, juvenile myoclonic epilepsy, and epilepsy with generalized tonic-clonic seizures alone (CAE, JAE, JME, and GGE-GTCS, respectively). GGE are characterized by high heritability, likely underlain by polygenetic mechanisms, which may relate to atypical neurodevelopmental trajectories. Age of onset ranges from pre-school years, for CAE, to early adulthood for GGE-GTCS. Traditionally, GGE have been considered benign, a belief contrary to evidence from neuropsychology studies conducted over the last two decades. In JME, deficits in executive and social functioning are common findings and relate to impaired frontal lobe function. Studies using neuropsychological measures and cognitive imaging paradigms provide evidence for hyperconnectivity between prefrontal and motor cortices, aberrant fronto-thalamo-cortical connectivity, and reduced fronto-cortical and subcortical gray matter volumes, which are associated with altered cognitive performance. Recent research has also identified associations between abnormal hippocampal morphometry and fronto-temporal activation during episodic memory. Longitudinal studies on individuals with newly diagnosed JME have observed cortical dysmaturation, which is paralleled by delayed cognitive development compared to the patients' peers. Comorbidities and cognitive deficits observed in other GGE subtypes, such as visuo-spatial and language deficits in both CAE and JAE, have also been correlated with atypical neurodevelopment. Although it remains unclear whether cognitive impairment profiles differ amongst GGE subtypes, effects may become more pronounced with disease duration, particularly in absence epilepsies. Finally, there is substantial evidence that patients with JME and their unaffected siblings share patterns of cognitive deficits, which is indicative of an underlying genetic etiology (endophenotype), independent of seizures and anti-epileptic medication.

Towards a Better Understanding of Cognitive Deficits in Absence Epilepsy: a Systematic Review and Meta-Analysis

Cognition in absence epilepsy (AE) is generally considered undisturbed. However, reports on cognitive deficits in AE in recent years have suggested otherwise. This review systematically assesses current literature on cognitive performance in children with AE. A systematic literature search was performed in Pubmed, Embase, Cochrane and Web of Science. All studies reporting on cognitive performance in children with AE were considered. In total 33 studies were eligible for inclusion. Neuropsychological tests were classified into the following domains: intelligence; executive function; attention; language; motor & sensory-perceptual examinations; visuoperceptual/visuospatial/visuoconstructional function; memory and learning; achievement. Random-effect meta-analyses were conducted by estimating the pooled mean and/or pooling the mean difference in case-control studies. Full-scale IQ in children with AE was estimated at 96.78 (95%CI:94.46–99.10) across all available studies and in case-control studies IQ was on average 8.03 (95%CI:-10.45- -5.61) lower. Verbal IQ was estimated at 97.98 (95%CI:95.80–100.16) for all studies and 9.01 (95%CI:12.11- -5.90) points lower in case-control studies. Performance IQ was estimated at 97.23 (93.24–101.22) for all available studies and 5.32 (95%CI:-8.27–2.36) points lower in case-control studies. Lower performance was most often reported in executive function (cognitive flexibility, planning, and verbal fluency) and attention (sustained, selective and divided attention). Reports on school difficulties, neurodevelopmental problems, and attentional problems were high. In conclusion, in contrast to common beliefs, lower than average neurocognitive performance was noted in multiple cognitive domains, which may influence academic and psychosocial development.

Clinical Significance of Incidental Rolandic Spikes in Children With Absence Epilepsy

PURPOSE

Absence epilepsy and benign epilepsy of childhood with central temporal spikes are common childhood epilepsy syndromes. Although 3-Hz generalized spike-wave discharges are almost always associated with absence seizures, rolandic spikes can be present in individuals without rolandic seizures. The co-occurrence of 3-Hz generalized spike-wave and rolandic spikes is very rare. Our objective was to compare clinical features of patients with absence epilepsy with and without rolandic spikes, to determine if the additional feature of rolandic spikes has any clinical significance.

METHODS

Clinical information of 17 children with absence epilepsy and rolandic spikes was compared to an age-matched control group of 90 children with absence epilepsy.

RESULTS

Although most patients had excellent seizure control at follow-up, epilepsy comorbidities (cognitive and emotional problems) were observed. Comparing study vs control groups, there was no difference with anxiety (2 [11.8%] vs 8 [9%]), behavioral issues (4 [23.5%] vs 10 [11%]), mood disorders (0 vs 2 [2%]), and attention-deficit hyperactivity disorder (4 [24%] vs 10 [11%]). Significant differences were also observed: more global-developmental (5 [29%] vs 5 [6%], P < .009) and expressive-language (4 [24%] vs 5 [6%], P < .034) delay and more difficulties with school performance (11 [65%] vs 32 [36%], P < .025), especially with language-related tasks (6 [35%] vs 5 [6%], P < .001).

CONCLUSION

Our results confirm the presence of additional epilepsy comorbidities in patients with absence epilepsy when rolandic spikes are present. Rolandic spikes in patients with absence epilepsy may be a marker of additional cognitive challenges that physicians should be aware of.

Lower myelin-water content of the frontal lobe in childhood absence epilepsy

OBJECTIVE

The frontal lobe in childhood absence epilepsy (CAE) might be affected due to the suggested involvement of the frontal lobe during absence seizures and reports on attentional deficits. Previously, subtle white matter abnormalities have been reported in CAE. However, the impact of one of the most characteristic components of the white matter, the myelin content, remains underdetermined. Therefore, this study investigated whether the myelin content in frontal areas is adversely affected in CAE compared to controls.

METHODS

Seventeen children with childhood absence epilepsy (mean age ± standard deviation [SD], 9.2 ± 2.1 years) and 15 age- and sex-matched controls (mean age ± SD, 9.8 ± 1.8 years) underwent neuropsychological assessment and a magnetic resonance imaging (MRI) examination. T2 relaxometry scans were used to distinguish myelin-water from tissue water and to determine the myelin-water fraction (MWF) in the frontal, temporal, parietal, occipital, and insular lobes. A linear regression model including age and sex as covariates was used to investigate group differences. Furthermore, the relationship of MWF with cognitive performance and epilepsy characteristics was determined.

RESULTS

The frontal lobe revealed a significantly lower myelin-water content in children with CAE compared to controls over the developmental age range of 6-12 years (5.7 ± 1.0% vs 6.6 ± 1.1%, P = 0.02). This association was not found for any of the other four lobes (P > 0.10). No significant relation was found between myelin-water content and cognitive performance or epilepsy characteristics.

SIGNIFICANCE

The lower frontal myelin-water content of children with CAE in comparison with healthy controls probably reflects an altered neurodevelopmental aspect in CAE, of which the underlying mechanisms still need to be unraveled.

Executive functioning in children with epilepsy: Genes matter

Pediatric epilepsy has emerged as a chronic medical disease with a characteristic behavioral and cognitive phenotype, which includes compromised executive functioning (EF) and attention-related deficits. However, considerable interindividual variability exists; children often display very different or even opposite outcomes, and some children are more likely than others to develop neurocognitive problems in the face of similar individual and disease-related problems. The factors responsible for this interindividual variability are still largely unknown, but we do know that some genetic factors render the developing brain more susceptible to damage or traumatic experiences than others. Dopamine availability has a neuromodulatory function in the prefrontal cortex (PFC) and especially affects EF. Dopamine availability relates to polymorphisms in the gene encoding catechol-O-methyltransferase (COMT Val158Met), which in turn is affected by the methylation state of its promoter. Allelic variation of the methylenetetrahydrofolate reductase (MTHFR C677T) gene, alters methylation and may influence the methylation state of the COMT promoter. Given this, we tested the hypothesis that these polymorphisms interact in children with epilepsy, and that variability in allelic expression is associated with variability in cognitive phenotype. Executive function was tested directly and indirectly (parent-rated) in 42 children between 5 and 12 years of age. The MTHFR T allele carriers performed worse than MTHFR homozygous CC carriers on indirect EF, and a significant decline was observed when T allele carriers had at least one met allele of the COMT gene, especially on Working Memory. Direct EF was significantly compromised in COMT Val/Val carriers where reduced dopamine availability seems to confer a higher risk in a test that requests a high degree of executive attention and planning. This finding suggests that in children with epilepsy, genes that influence methylation and dopamine availability affect PFC-related EF. Therefore, we should consider genetic vulnerability as a polygenic risk, which might predispose for a particular phenotype and include specific genetic signatures as part of each patient's behavioral and cognitive profile from the moment that we start to take care of the child.

Cognitive development in absence epilepsy during long-term follow-up

Absence epilepsy (AE) has been associated with lower than average cognitive functioning, which are clinically relevant in some and may predispose to problems later in life. This study aimed to assess cognitive development during long-term follow-up in children with AE. Thirty-one children with AE, who had undergone two neuropsychological assessments between 2010 and 2017 were analyzed retrospectively. Cognitive measurements were 1.7 ± 0.95 years apart. The difference in neurocognitive test scores was assessed on a group level and on an individual level using reliable change methodology. Results show that sustained attention was lower at the first measurement compared to the normative mean. Sustained attention improved during follow-up and 7 out of 14 children showed improvement after correction for practice effects. Receptive vocabulary showed a decline over time, but did not differ from the normative mean. Significant lower mean group scores were present for performance IQ, perceptual organization, processing speed, simple reaction times, and visual motor integration, while being stable over time in the majority of children. Cognitive development was not associated with seizure freedom. Mild-to-severe academic underachievement was present in 65% and comorbidities that might affect learning in 38%. This study in children with AE showed improvement in sustained attention during long-term follow-up while other cognitive weaknesses persisted over time, regardless of seizure freedom.

Executive functioning phenotypes in youth with epilepsy

OBJECTIVE

The objectives of this study were to identify executive functioning (EF) phenotypes in youth with epilepsy and to examine whether phenotypes differ on psychosocial and medical outcomes (i.e., absence/presence of seizures in the past three months), health-related quality of life (HRQOL), and emotional and behavioral functioning.

METHODS

Youth 5-18 years with diagnosed epilepsy and caregivers completed a battery of questionnaires as part of a larger national validation of the Pediatric Quality of Life (PedsQL) Epilepsy Module. The primary measure of interest was the Behavior Rating Inventory of Executive Function-Parent Form. Medical chart reviews and demographic data were also collected. Latent class analysis was used to identify EF phenotypes. Chi-square and analyses of covariance (ANCOVA) were conducted to examine EF phenotype group differences on seizure outcomes, HRQOL, and behavioral and emotional functioning.

RESULTS

Two-hundred and thirty-seven children with epilepsy (M_age = 11.2 years; 56% female; 60% White: Non-Hispanic; 55% experienced seizures in the past three months) and their caregivers participated. Four EF phenotypes were identified: Group 1 - No EF deficits (45% of sample), Group 2 - Global EF deficits (29% of sample), Group 3 - Behavioral Regulation + Working Memory deficits (8% of sample), and Group 4 - Metacognitive deficits (17% of sample). No significant EF phenotype group differences were found for seizure characteristics. The ANCOVAs indicated significant EF phenotype group differences on HRQOL (parent-reported Impact, Cognitive, Sleep, EF, and Mood/Behavior and child-reported Cognitive, Sleep, EF, and Mood/Behavior subscales; ps < .001) and emotional and behavioral functioning (Externalizing, Internalizing, and Behavioral Symptom Index; ps < .001), with the Global EF deficits (Group 2) and Behavioral Regulation + Working Memory deficits groups (Group 3) demonstrating the greatest level of impairment.

CONCLUSION

Phenotypic variability in EF is significantly related to patient-reported outcomes. Interventions addressing EF deficits need to be individualized to a child's particular EF phenotype to achieve optimal outcomes.

Imaging episodic memory during development and childhood epilepsy

Epilepsy affects 2.2 million adults in the USA, with 1 in 26 people developing epilepsy at some point in their lives. Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy as medial structures, and the hippocampus in particular, are prone to generating seizures. Selective anterior temporal resection (which removes the hippocampus) is the most effective intractable TLE treatment, but given the critical role of the mesial temporal lobe in memory functioning, resection can have negative effects on this crucial cognitive skill. To minimize the adverse impact of temporal lobe surgery on memory functioning, reliable pre-surgical guides are needed. Clinical functional magnetic resonance imaging (fMRI) provides reliable, noninvasive guidance of language functioning and plays a growing role in the pre-surgical evaluation for epilepsy patients; however, localization of memory function in children with epilepsy using fMRI has not been established. Aside from the lack of neuroimaging memory studies in children with TLE, studies of typical development are limited. This review will focus on the functional anatomy of memory systems throughout development, with a focus on TLE. TLE provides the ideal model from which to understand memory function and the limits of plasticity and compensation/reorganization throughout development.

Memory in children with epilepsy: Utility of the WRAML-2 in generalized and focal epilepsy syndromes

The material-specific model for memory impairment predicts that verbal memory deficits are seen with left temporal seizures, and visual memory deficits are seen with right temporal seizures (Henkin et al., 2005). In pediatric epilepsy, seizure pathology has not always yielded the expected material-specific memory profiles. This study used the Wide Range Assessment of Memory and Learning-Second Edition (WRAML-2) to assess memory functioning among pediatric patients with epilepsy. The WRAML-2 was administered to 180 youth with epilepsy during their neuropsychological evaluations. Memory and recognition scores correlated significantly with epilepsy severity variables. There were no significant differences in verbal and visual memory and recognition index scores among patients with generalized epilepsy or among those with lateralized or localized electroencephalography (EEG) patterns and lesions on imaging. However, clinically meaningful verbal versus visual discrepancy scores were significantly related to lateralized abnormalities on EEG and magnetic resonance imaging (MRI) results. Most patients with right hemisphere pathology showed the expected material-specific visual memory deficits, while fewer than 15% of the left hemisphere cases showed the expected verbal memory deficits. Over one-third of those with identified left-sided pathology showed clinically significant deficits in visual memory. Findings are incongruent with the material-specific memory model and reflect the fact that early developmental neurological insults can lead to functional reorganization/crowding effects in children with left hemisphere epilepsy. On exploratory analyses, there were no significant differences in discrepancy scores among participants with left, right, and bilateral languages on Wada and functional MRI (fMRI). However, those with right and bilateral language dominance were more likely to show discrepancies that were incongruent with the material-specific model.

Modulation of P2X Purinoceptor 3 (P2X3) in Pentylenetetrazole-Induced Kindling Epilepsy in Rats

Background

Epilepsy is a complex neurologic disorder with abnormal electrical impulses in the brain. A crucial role of purinergic signalling in the proper working of the nervous system has been reported but much less is known about the modulation of P2X3 purinergic receptors in epilepsy. This study investigated the effect of NF110, a potent P2X3 receptor antagonist, in the rat epilepsy model of pentylenetetrazole (PTZ)-induced kindling.

Material/Methods

The mean kindling score, motor activity, locomotion, emotional tension, anxiety, discrimination ability, learning, memory, serum neuron-specific enolase (sNSE), hippocampal IL-1β and TNF-α, thiobarbituric acid-reactive substance (TBARS), catalase (CAT) and reduced glutathione (GSH), and mitochondrial complex I, II, and IV levels of PTZ-kindling animals were assessed.

Results

The PTZ-kindling animals have shown impaired motor activity, locomotion, discrimination ability, learning, and memory, along with increased emotional tension, anxiety, neuronal damage (increased sNSE), hippocampal pro-inflammatory mediators (increased IL-1β and TNF-α), oxidative stress (increased TBARS, decreased GSH and CAT), and mitochondrial dysfunction. The administration of NF110 in 3 different doses has significantly and dose-dependently corrected PTZ-kindling-induced impaired behavior, learning, memory, locomotion, motor activity, discrimination ability, neuronal damage, hippocampal inflammation, oxidative stress, and mitochondrial dysfunction. These beneficial effects of NF110 in PTZ-kindling animals were significantly abolished by the administration of the P2X agonist α, β methylene-ATP.

Conclusions

P2X3 receptors play a very important role in kindling epilepsy and further research should be done to design P2X3 modulators for their possible therapeutic benefits in epileptic disorders.

Neurocognitive deficits in children with chronic health conditions

Over 4 million children in the United States suffer from chronic health conditions, including cancer, sickle cell disease, and diabetes. Because of major advances in the early identification and treatment of these conditions, survival rates for these children continue to rise, and the majority now lives into adulthood. However, increases in survival have come with costs related to long-term effects of disease processes and treatments. Foremost among these consequences is impairment in brain development and neurocognitive function that may affect a substantial portion of children with chronic health conditions and follow many into adulthood. Impaired cognitive function may contribute to impairment in educational and occupational attainment, mental health, and quality of life for children with chronic conditions. Despite the significance and scope of this problem, advances in the identification and understanding of neurocognitive problems and the delivery of effective clinical care have been hindered in part because research has been "siloed"-conducted on each chronic condition in isolation. This review examines, for the first time, neurocognitive problems in a selected set of 6 chronic pediatric health conditions-leukemia, brain tumors, sickle cell disease, congenital heart disease, Type 1 diabetes, and traumatic brain injury-to define the magnitude of the problem and identify directions for future research and clinical care. Psychologists from many areas of specialization, including pediatric psychology, educational and school psychology, neuropsychology, behavioral medicine, and adult primary care, are uniquely positioned to contribute to every phase of this work, including research, identification, and intervention. (PsycINFO Database Record

Stroop Color-Word Interference Test: Normative data for Spanish-speaking pediatric population

OBJECTIVE

To generate normative data for the Stroop Word-Color Interference test in Spanish-speaking pediatric populations.

METHOD

The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the Stroop Word-Color Interference test as part of a larger neuropsychological battery. The Stroop Word, Stroop Color, Stroop Word-Color, and Stroop Interference scores were normed using multiple linear regressions and standard deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in the analyses.

RESULTS

The final multiple linear regression models showed main effects for age on all scores, except on Stroop Interference for Guatemala, such that scores increased linearly as a function of age. Age2 affected Stroop Word scores for all countries, Stroop Color scores for Ecuador, Mexico, Peru, and Spain; Stroop Word-Color scores for Ecuador, Mexico, and Paraguay; and Stroop Interference scores for Cuba, Guatemala, and Spain. MLPE affected Stroop Word scores for Chile, Mexico, and Puerto Rico; Stroop Color scores for Mexico, Puerto Rico, and Spain; Stroop Word-Color scores for Ecuador, Guatemala, Mexico, Puerto Rico and Spain; and Stroop-Interference scores for Ecuador, Mexico, and Spain. Sex affected Stroop Word scores for Spain, Stroop Color scores for Mexico, and Stroop Interference for Honduras.

CONCLUSIONS

This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate approach to interpret the Stroop Word-Color Interference test in pediatric populations.

Pattern of executive functioning in adolescents with epilepsy: A multimethod measurement approach

Youth with epilepsy demonstrate deficits in executive functioning (EF), the skills necessary for goal-directed behavior (e.g., problem-solving, initiating, monitoring, organization, planning, and working memory). Despite 30-50% of youth with epilepsy demonstrating EF deficits, no extant studies have utilized both performance and questionnaire-based measures to examine the pattern of EF deficits in adolescents with epilepsy. Study aims were to 1) identify the pattern of EF deficits in adolescents with epilepsy and 2) identify which assessment tools are most sensitive to EF deficits in this population (adolescents, ages 13-17, with epilepsy). An exploratory aim was to examine group differences on measures of EF by epilepsy type. Standard performance-based neuropsychological measures (Wechsler Intelligence Scale for Children - Version V or Wechsler Adult Intelligence Scale Working Memory Index-Version IV, Delis Kaplan Executive Functioning System, NIH Toolbox, Test of Everyday Attention for Children) and the Behavior Rating Inventory of Executive Functioning (BRIEF) comprised the multimethod assessment battery. Depending on the measure, 30% of adolescents with epilepsy had deficits in working memory, 17% in cognitive flexibility/problem solving, 6% in inhibition, and 18% in planning/organization. Attention was a significant problem for 15% of adolescents with epilepsy. Correlations among the various EF measures were quite poor. Across various EF domains, results indicated that adolescents with localization-related epilepsy demonstrated better EF skills compared to adolescents with unclassified epilepsy. Overall, our findings suggest that executive functioning deficits are selective and different from those observed in other neurological populations (e.g., attention deficit hyperactivity disorder (ADHD), traumatic brain injury) where problems with self-regulation (i.e., inhibition, planning/organization) are more pronounced. These findings support utilizing multiple measures, including both performance-based neuropsychological tests and parent- and self-reports, to assess executive functioning difficulties in adolescents with epilepsy as they are uniquely sensitive to executive functioning domains. Adolescents with unclassified epilepsy also appear to be at higher risk for EF deficits and thus represent an important group to target for intervention.

Neurocognitive Comorbidities in Pediatric Epilepsy: Lessons in the Laboratory and Clinical Profile

Children with epilepsy are at risk for a variety of neurocognitive comorbidities. Animal models have increased our understanding about the neurobiological mechanisms underlying the association between seizures and these comorbidities. This article starts with an overview of the current data on animal model research, studying the influence of early-life seizures, followed by a summary of potential cellular and molecular mechanisms by which seizures can affect cognitive development. We then describe specific abnormal neuropsychological profiles that accompany specific pediatric epilepsy syndromes. Finally, we offer a potential guideline to the treatment and management of children with epilepsy and its neurocognitive comorbidities.

Facial emotion perception in patients with epilepsy: A systematic review with meta-analysis

Facial emotion perception is a fundamental social competency relying on a specialised, yet distributed, neural network. This review aimed to determine whether patients with epilepsy have facial emotion perception accuracy impairments overall, or for a subset of emotions (anger, disgust, happiness, sadness, fear, and surprise), and the relationship to epilepsy type, demographic/treatment variables, and brain organisation. Database searches used PRISMA guidelines with strict inclusion/exclusion criteria. Thirty included studies assessed patients with temporal lobe (TLE; n=709), frontocentral (FCE; n=22), and genetic generalised (GGE; n=48) epilepsy. Large deficits emerged in patients with epilepsy compared to controls (n=746; Hedges' g=0.908-1.076). Patients with TLE were significantly impaired on all emotions except surprise; patients with GGE were significantly impaired in anger, disgust, and fear perception. Meta-regression of patients with TLE revealed younger age at testing was associated with lower accuracy. This review provides evidence for marked global deficits of emotion perception in epilepsy, with differential emotion-specific impairment patterns in patients with TLE and GGE.

Seizure-related variables are predictive of attention and memory in children with epilepsy

Children with epilepsy (CWE) are at greater risk for cognitive deficits and behavioral difficulties than are typically developing healthy children, and particular epileptic symptoms and treatments may contribute to this risk. The current study examined the relationships between four seizure-related variables and attention and memory functioning in a sample of 207 CWE (ages 6-16) using both neurocognitive and parent/teacher-report measures. Sociodemographic, medical, and neuropsychological data were collected from patients' medical charts in a retrospective fashion. Hierarchical multiple regressions were performed with sociodemographic variables (age, gender, race) entered as step one and seizure-related variables (number of anti-epileptic drugs [AEDs], EEG laterality, EEG lobe of focus, lifetime seizure duration) entered as step two. Results indicated that seizure-related variables were consistently predictive of poor cognitive performances above and beyond sociodemographic variables, although only minimally predictive of parent/teacher-reports. A longer duration of seizure burden and greater number of AEDs were robust predictors of performances on most cognitive measures. These findings indicate that CWE with long lifetime seizure durations and multiple AEDs are at risk for inefficiencies in attention and memory. Knowledge of this risk will allow treating providers greater accuracy and precision when planning medical treatment and making recommendations to families.

The role of executive functioning in memory performance in pediatric focal epilepsy

OBJECTIVE

Learning and memory are essential for academic success and everyday functioning, but the pattern of memory skills and its relationship to executive functioning in children with focal epilepsy is not fully delineated. We address a gap in the literature by examining the relationship between memory and executive functioning in a pediatric focal epilepsy population.

METHODS

Seventy children with focal epilepsy and 70 typically developing children matched on age, intellectual functioning, and gender underwent neuropsychological assessment, including measures of intelligence (Wechsler Abbreviated Scale of Intelligence [WASI]/Differential Ability Scales [DAS]), as well as visual Children's Memory Scale (CMS Dot Locations) and verbal episodic memory (Wide Range Assessment of Memory and Learning [WRAML] Story Memory and California Verbal Learning Test for Children [CVLT-C]). Executive functioning was measured directly (WISC-IV Digit Span Backward; Clinical Evaluation of Language Fundamentals, Fourth Edition (CELF-IV) Recalling Sentences) and by parent report (Behavior Rating Inventory of Executive Function [BRIEF]).

RESULTS

Children with focal epilepsy had lower delayed free-recall scores than controls across visual and verbal memory tasks (p = 0.02; partial η² = 0.12). In contrast, recognition memory performance was similar for patients and controls (p = 0.36; partial η² = 0.03). Children with focal epilepsy demonstrated difficulties in working memory (p = 0.02; partial η² = 0.08) and planning/organization (p = 0.02) compared to controls. Working memory predicted 9-19% of the variance in delayed free recall for verbal and visual memory; organization predicted 9-10% of the variance in verbal memory. Patients with both left and right focal epilepsy demonstrated more difficulty on verbal versus visual tasks (p = 0.002). Memory performance did not differ by location of seizure foci (temporal vs. extratemporal, frontal vs. extrafrontal).

SIGNIFICANCE

Children with focal epilepsy demonstrated memory ability within age-level expectations, but delayed free recall was inefficient compared to typically developing controls. Memory difficulties were not related to general cognitive impairment or seizure localization. Executive functioning accounted for significant variance in memory performance, suggesting that poor executive control negatively influences memory retrieval.

List-learning and verbal memory profiles in childhood epilepsy syndromes

Findings of material-specific influences on memory performance in pediatric epilepsy are inconsistent and merit further investigation. This study compared 90 children (aged 6years to 16years) with childhood absence epilepsy (CAE), frontal lobe epilepsy (FLE), and temporal lobe epilepsy (TLE) to determine whether they displayed distinct list-learning and verbal memory profiles on the California Verbal Learning Test - Children's Version (CVLT-C). Group comparison identified greater risk of memory impairment in children with TLE and FLE syndromes but not for those with CAE. While children with TLE performed worst overall on Short Delay Free Recall, groups with TLE and FLE performed similarly on Long Delay Free Recall. Contrast indices were then employed to explore these differences. Children with TLE demonstrated a significantly greater retroactive interference (RI) effect compared with groups with FLE and CAE. Conversely, children with FLE demonstrated a significantly worse learning efficiency index (LEI), which compares verbal memory following repetition with initial recall of the same list, than both children with TLE and CAE. These findings indicated shallow encoding related to attentional control for children with FLE and retrieval deficits in children with TLE. Finally, our combined sample showed significantly higher rates of extreme contrast indices (i.e., 1.5 SD difference) compared with the CVLT-C standardization sample. These results underscore the high prevalence of memory dysfunction in pediatric epilepsy and offer support for distinct patterns of verbal memory performance based on childhood epilepsy syndrome.

Use of a Cumulative Risk Scale to Predict Poor Intellectual and Academic Outcomes in Childhood Epilepsy

Discrete risk factors for poor outcomes in childhood epilepsy have been identified, but it is unclear whether the combined effect of several risk factors better predicts outcome. The Epilepsy Cumulative Risk Scale was developed to quantify cumulative risk for poor outcomes in childhood epilepsy. Participants included 156 clinic-referred children with epilepsy. The Epilepsy Cumulative Risk Scale was developed using variables previously associated with functional outcomes. Scale utility was examined through its association with intellectual and academic functioning. All Epilepsy Cumulative Risk Scale variables were significantly associated with functioning. The Total Score (ie, cumulative effect) was most strongly correlated with cognition and academic skills. A Total Score ≥ 5 had the best sensitivity and specificity for differentiating those at high risk for poor outcomes. The Epilepsy Cumulative Risk Scale shows promise as a practical, data-driven tool for quantification of cumulative risk for poor outcomes in childhood epilepsy and may be helpful in detecting those needing referral for additional services.

Relationship between social competence and neurocognitive performance in children with epilepsy

Epilepsy may affect a child's social skills and social cognition. The purpose of the study was to examine associations between sociocognitive skills and neurocognitive performance in children with epilepsy. Thirty-five children with epilepsy between the ages of 7 and 12 years (25 with partial and 10 with generalized epilepsy) and 30 controls participated. Theory of Mind (ToM) tasks, Social Cognition Questionnaire proposed by Saltzman-Benaiah and Lalonde (2007), and Social Skills Rating System were used to assess social competence and sociocognitive skills. Neurocognitive performance was assessed using the NEPSY battery. Children with epilepsy demonstrated more difficulties in understanding false belief (p<.001) and intentional lying (p<.05) and exhibited more behavioral problems (p<.05). Notably, their social skills were at the same level as typically developing peers. Children with epilepsy performed significantly worse in attention, executive, verbal, and fine motor tasks (p<.05). We found positive correlations between the understanding of false belief and in executive (r=.6, p<.05), verbal (r=.45-.49, p<.05), and visuospatial skills (r=.34-.48, p<0.01). Children with generalized epilepsy had more problems in memory tasks (p<.05) and understanding of sarcasm (p<.05) compared with children with partial epilepsy. An age of onset over 9.1 years was positively associated with ToM skills (r=.42, p<.05). In conclusion, better ToM in children with better executive functions, and language and visuospatial skills was revealed. The type of epilepsy and age of onset significantly affected ToM skills.

There are laterality effects in memory functioning in children/adolescents with focal epilepsy

In a sample of individuals with childhood focal epilepsy, children/adolescents with left hemisphere foci outperformed those with right foci on both measures of nonverbal learning. Participants with left foci performed worse than controls on paired associate delayed recall and semantic memory, and they had greater laterality effects in IQ. Participants with right foci performed worse than controls on delayed facial recognition. Both groups displayed reduced focused attention and poor passage retention over time. Although participants with bilateral foci displayed poor learning and lower IQ than controls, they did not have worse impairment than those with a unilateral focus.

Temporal auditory processing and phonological awareness in children with benign epilepsy with centrotemporal spikes

The aim of this research was to analyze temporal auditory processing and phonological awareness in school-age children with benign childhood epilepsy with centrotemporal spikes (BECTS). Patient group (GI) consisted of 13 children diagnosed with BECTS. Control group (GII) consisted of 17 healthy children. After neurological and peripheral audiological assessment, children underwent a behavioral auditory evaluation and phonological awareness assessment. The procedures applied were: Gaps-in-Noise test (GIN), Duration Pattern test, and Phonological Awareness test (PCF). Results were compared between the groups and a correlation analysis was performed between temporal tasks and phonological awareness performance. GII performed significantly better than the children with BECTS (GI) in both GIN and Duration Pattern test (P < 0.001). GI performed significantly worse in all of the 4 categories of phonological awareness assessed: syllabic (P = 0.001), phonemic (P = 0.006), rhyme (P = 0.015) and alliteration (P = 0.010). Statistical analysis showed a significant positive correlation between the phonological awareness assessment and Duration Pattern test (P < 0.001). From the analysis of the results, it was concluded that children with BECTS may have difficulties in temporal resolution, temporal ordering, and phonological awareness skills. A correlation was observed between auditory temporal processing and phonological awareness in the suited sample.

Altered intrathalamic GABAA neurotransmission in a mouse model of a human genetic absence epilepsy syndrome

We previously demonstrated that heterozygous deletion of Gabra1, the mouse homolog of the human absence epilepsy gene that encodes the GABAA receptor (GABAAR) α1 subunit, causes absence seizures. We showed that cortex partially compensates for this deletion by increasing the cell surface expression of residual α1 subunit and by increasing α3 subunit expression. Absence seizures also involve two thalamic nuclei: the ventrobasal (VB) nucleus, which expresses only the α1 and α4 subtypes of GABAAR α subunits, and the reticular (nRT) nucleus, which expresses only the α3 subunit subtype. Here, we found that, unlike cortex, VB exhibited significantly reduced total and synaptic α1 subunit expression. In addition, heterozygous α1 subunit deletion substantially reduced miniature inhibitory postsynaptic current (mIPSC) peak amplitudes and frequency in VB. However, there was no change in the expression of the extrasynaptic α4 or δ subunits in VB and, unlike other models of absence epilepsy, no change in tonic GABAAR currents. Although heterozygous α1 subunit knockout increased α3 subunit expression in medial thalamic nuclei, it did not alter α3 subunit expression in nRT. However, it did enlarge the presynaptic vesicular inhibitory amino acid transporter puncta and lengthen the time constant of mIPSC decay in nRT. We conclude that increased tonic GABAA currents are not necessary for absence seizures. In addition, heterozygous loss of α1 subunit disinhibits VB by substantially reducing phasic GABAergic currents and surprisingly, it also increases nRT inhibition by prolonging phasic currents. The increased inhibition in nRT likely represents a partial compensation that helps reduce absence seizures.

Memory in children with epilepsy: a systematic review

PURPOSE

Research suggests an increased risk for cognitive impairment in childhood epilepsy with memory being one area of cognition most likely to be affected. Understanding the prevalence and predictors of memory difficulties may help improve awareness of the difficulties and allow efficacious supports to be put in place.

METHOD

A systematic review was carried out using the search terms 'memory', 'children' and 'epilepsy' in the database PUBMED. Eighty-eight studies met inclusion criteria. The review focuses on comparisons of memory scores of children with epilepsy and controls, and comparison of memory scores of children with epilepsy to normative scores. Predictors of memory impairment and the effect of surgery on memory functioning are also reviewed.

RESULTS

The majority (78%) of studies reviewed revealed that children with epilepsy scored lower than controls and normative scores on measures of memory. Post-surgery, memory scores were reported to improve in 50% of studies. Predictors of memory impairment included a greater number of AEDs used, younger age of onset, increased seizure frequency and longer duration of epilepsy.

CONCLUSION

Children with epilepsy have a high frequency of memory impairments. However, the exact prevalence of difficulties is not clear due to the lack of population-based data. Most studies have not controlled for IQ and thus it is unclear if difficulties are always related to global cognitive difficulties. There is need for future population-based studies and studies focussing on the neurobiology of memory problems in children with epilepsy.

Memory functioning in children with epilepsy: frontal lobe epilepsy, childhood absence epilepsy, and benign epilepsy with centrotemporal spikes

Specific cognitive deficits have been identified in children with epilepsy irrespective of results on intelligence tests. Memory deficits are traditionally attributed to temporal lobe epilepsy, whereas the impact of frontal lobe epilepsy on memory functions has remained controversial. The aim of this study was the examination of memory abilities in other childhood common epilepsy syndromes (frontal lobe epilepsy (FLE), childhood absence epilepsy (CAE), and benign epilepsy with centrotemporal spikes (BECTS)) and the influence of epilepsy-related variables. Memory was examined in 90 children with epilepsy (each epilepsy group consisted of 30 children), aged 6–15, and compared with 30 control children. Children with FLE showed significant deficits in verbal and visual memory. In addition, type of epilepsy, earlier age at epilepsy onset, and longer active duration of epilepsy were associated with memory problems. Seizure frequency and treatment, however, did not influence memory performance. This study indicates that children with FLE show greater risk of developing memory deficits than children with CAE or BECTS, thus highlighting the importance of assessing also memory functions in frontal lobe epilepsy.

Visual memory after epilepsy surgery in children: a standardized regression-based analysis of group and individual outcomes

Visual memory is vulnerable to epilepsy surgery in adults, but studies in children suggest no change or small improvements. We investigated visual memory after epilepsy surgery, both group-wise and in individual children, using two techniques to assess change: 1) repeated measures analysis of variance (ANOVA) and 2) an empirically based technique for detecting cognitive change [standardized regression-based (SRB) analysis]. A prospective cohort consisting of 21 children completed comprehensive assessments of memory both before surgery (T0) and 6 (T1), 12 (T2), and 24 months (T3) after surgery. For each patient, two age- and gender-matched controls were assessed with the same tests at the same intervals. Repeated measures ANOVA replicated the results of previous studies reporting no change or minor improvements after surgery. However, group analysis of SRB results eliminated virtually all improvements, indicating that the ANOVA results were confounded by practice effects. Standardized regression-based group results showed that in fact patients scored lower after surgery than would be predicted based on their presurgical performance. Analysis of individual SRB results showed that per visual memory measure, an average of 18% of patients obtained a significantly negative SRB score, whereas, on average, only 2% obtained a significantly positive SRB score. At T3, the number of significantly negative SRB scores outweighed the number of significantly positive SRB scores in 62% of patients. There were no clear associations of clinical variables (including side and site of surgery and postsurgical seizure freedom) with memory outcome. The present analysis revealed that given their individual presurgical functioning, many children obtained disappointing results on some visual memory tests after epilepsy surgery. Comparison of the SRB analysis with ANOVA results emphasizes the importance of empirically based techniques for detecting cognitive effects of epilepsy surgery in childhood.

Effects of grape seed proanthocyanidin extract on pentylenetetrazole-induced kindling and associated cognitive impairment in rats

Numerous studies have demonstrated the antioxidant effects of grape seed proanthocyanidin extract (GSPE). The generation of free radicals and the ensuing apoptosis may contribute to the pathogenesis of epilepsy; therefore, in the present study, we examined the effects of GSPE on cognitive impairment and neuronal damage induced by chronic seizures in rats. Seizures were induced by a daily intraperitoneal (i.p.) injection of pentylenetetrazole (PTZ; 35 mg/kg/day, 36 days). Two other groups were treated with GSPE (100 or 200 mg/kg/day, orally) for 24 days and then for 36 days prior to each PTZ injection. After the final PTZ injection, hippocampus-dependent spatial learning was assessed using the Morris water maze (MWM). The rats were then sacrificed for the measurement of hippocampal malondialdehyde (MDA, a measure of lipid peroxidation) and glutathione (GSH, a measure of endogenous antioxidant capacity) levels, and for the expression of pro-apoptotic factors [cytochrome c (Cyt c), caspase‑9 and caspase‑3]. The mitochondrial generation of reactive oxygen species (ROS), degree of mitochondrial swelling, neuronal damage and mitochondrial ultrastructure were also examined. Performance in the MWM was markedly impaired by PTZ-induced seizures, as evidenced by longer escape latencies during training and fewer platform crossings during the probe trial. This cognitive decline was accompanied by oxidative stress (MDA accumulation, ROS generation, reduced GSH activity), an increased expression of pro-apoptotic proteins, as well as damage to CA1 pyramidal neurons and the mitochondria. Pre-treatment with GSPE dose‑dependently reversed PTZ-induced impaired performance in the MWM, oxidative stress, mitochondrial ROS generation, the expression of pro-apoptotic proteins and neuronal and mitochondrial damage. Thus, GSPE may reverse the hippocampal dysfunction induced by chronic seizures, by reducing oxidative stress and preserving mitochondrial function.

Current advances in childhood absence epilepsy

BACKGROUND

Childhood absence epilepsy is an age-dependent, idiopathic, generalized epilepsy with a characteristic seizure appearance. The disorder is likely to be multifactorial, resulting from interactions between genetic and acquired factors, but the debate is still open. We review recent studies on different aspects of childhood absence epilepsy and also to describe new concepts.

METHODS

Data for this review were identified using Medline and PubMed survey to locate studies dealing with childhood absence epilepsy. Searches included articles published between 1924 and 2013.

RESULTS

The diagnosis comprises predominant and associated seizure types associated with other clinical and electroencephalographic characteristics. Many studies have challenged the prevailing concepts, particularly with respect to the pathophysiological mechanisms underlying the electroencephalographic seizure discharges. Childhood absence epilepsy fits the definition of system epilepsy as a condition resulting from the persisting susceptibility of the thalamocortical system as a whole to generate seizures. This syndrome, if properly defined using strict diagnostic criteria, has a good prognosis. In some cases, it may affect multiple cognitive functions determining risk for academic and functional difficulties; the detection of children at risk allows tailored interventions. Childhood absence epilepsy is usually treated with ethosuximide, valproate, lamotrigine, or levetiracetam, but the most efficacious and tolerable initial empirical treatment has not been well defined.

CONCLUSIONS

We review recent studies and new concepts on the electroclinical features and pathophysiological findings of childhood absence epilepsy in order to highlight areas of consensus as well as areas of uncertainty that indicate directions for future research.