Attention, memory, and behavioral adjustment in children with frontal lobe epilepsy

Mathematics Skills in Epilepsy: A Systematic Review and Meta-Analysis

Mathematics incorporates a broad range of skills, which includes basic early numeracy skills, such as subitizing and basic counting to more advanced secondary skills including mathematics calculation and reasoning. The aim of this review was to undertake a detailed investigation of the severity and pattern of early numeracy and secondary mathematics skills in people with epilepsy. Searches were guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Twenty adult studies and 67 child studies were included in this review. Overall, meta-analyses revealed significant moderate impairments across all mathematics outcomes in both adults (g= -0.676), and children (g= -0.593) with epilepsy. Deficits were also observed for specific mathematics outcomes. For adults, impairments were found for mathematics reasoning (g= -0.736). However, two studies found that mathematics calculation was not significantly impaired, and an insufficient number of studies examined early numeracy skills in adults. In children with epilepsy, significant impairments were observed for each mathematics outcome: early numeracy (g= -0.383), calculation (g= -0.762), and reasoning (g= -0.572). The gravity of impairments also differed according to the site of seizure focus for children and adults, suggesting that mathematics outcomes were differentially vulnerable to the location of seizure focus.

Brain language networks and cognitive outcomes in children with frontotemporal lobe epilepsy

Introduction

Pediatric frontal and temporal lobe epilepsies (FLE, TLE) have been associated with language impairments and structural and functional brain alterations. However, there is no clear consensus regarding the specific patterns of cerebral reorganization of language networks in these patients. The current study aims at characterizing the cerebral language networks in children with FLE or TLE, and the association between brain network characteristics and cognitive abilities.

Methods

Twenty (20) children with FLE or TLE aged between 6 and 18 years and 29 age- and sex-matched healthy controls underwent a neuropsychological evaluation and a simultaneous functional near-infrared spectroscopy and electroencephalography (fNIRS-EEG) recording at rest and during a receptive language task. EEG was used to identify potential subclinical seizures in patients. We removed these time intervals from the fNIRS signal to investigate language brain networks and not epileptogenic networks. Functional connectivity matrices on fNIRS oxy-hemoglobin concentration changes were computed using cross-correlations between all channels.

Results and discussion

Group comparisons of residual matrices (=individual task-based matrix minus individual resting-state matrix) revealed significantly reduced connectivity within the left and between hemispheres, increased connectivity within the right hemisphere and higher right hemispheric local efficiency for the epilepsy group compared to the control group. The epilepsy group had significantly lower cognitive performance in all domains compared to their healthy peers. Epilepsy patients' local network efficiency in the left hemisphere was negatively associated with the estimated IQ (p = 0.014), suggesting that brain reorganization in response to FLE and TLE does not allow for an optimal cognitive development.

Impairment of cognitive functions in children and adolescents with focal epilepsy

Introduction

Frontal Lobe Epilepsy (FLE) and Temporal Lobe Epilepsy (TLE) are the two most frequent types of focal epilepsies and they are connected with difficulties in cognitive functioning. Despite multiple trials to systematize profile of cognitive functioning among children with epilepsy by researchers, the available data are ambiguous. The aim of our study was to compare the cognitive function of children upon diagnosis of TLE and FLE and during follow-up and to compare with a control group of healthy children.

Material and methods

Study included 39 patients with newly diagnosed TLE, 24 patients with FLE whose first epileptic seizure occurred between their 6th and 12th year of life and 24 healthy children matched by age, sex and IQ level. Neuropsychological examination was performed the moment of diagnosis and 2-3 years later using diagnostic tools validated and standardized to the patient's age. Intergroup comparison was conducted in both stages of study. Also, correlation between localization of epileptic focus and cognitive difficulties was analysed.

Results

Children with FLE and TLE accomplished worse results in most of the cognitive tasks compared to the control group already in the initial examination. Patients with FLE presented difficulties in memorizing verbal and visual material, attention and in learning new information. Patients with TLE had difficulties in tasks engaging verbal and non-verbal memory and attention. In the follow-up, patients with FLE presented more severe cognitive impairment compared with the other groups. Despite similar tendencies among children with TLE significantly worse results in tasks engaging verbal memory and attention were observed among patients with FLE. It is noteworthy that patients suffering from FLE and TLE present deficits in many aspects of cognitive functioning already at the time of diagnosis.

Conclusion

Children and adolescents suffering from epilepsy are at risk of psychosocial difficulties, emotional disorders and mental illnesses. Thus, full assessment of cognitive function is essential in this patient group not only at the moment of diagnosis but also during follow-up in order to quickly introduce an individual support system.

The influence of methylphenidate on sustained attention in paediatric acquired brain injury: a meta-analytical review

Impairment in sustained attention is a common consequence of childhood Acquired Brain Injury (ABI). Whilst methylphenidate provides promise in enhancing "attention" as a unitary construct, little work has explored its effectiveness upon individual attentional domains. The current systematic review and meta-analysis evaluates the utility of methylphenidate on sustained attentional performance across childhood ABI groups. Five databases (PsycINFO, MEDLINE, Embase, Scopus & Cochrane Library) were searched for relevant articles from their inception to March 2022. A purpose-developed evaluation tool was used to assess each study's research quality (QuEST:MAP). Nine of the 1600 identified articles were included within this review (n = 259). Meta-analytical findings reported an overall significant benefit of methylphenidate on sustained attention in childhood ABI (g = -0.33, 95% CI: -0.62 to -0.04). Associated summary effect sizes were relatively small, particularly when adjusting for outlier cases. Subgroup analyses identified a significantly greater benefit of methylphenidate in clinical subgroups with comorbid ADHD diagnoses (p < .01). The current evidence base is characterized by small-scale clinical trials with variable research quality and low generalizability. Further robust research is needed to quantify methylphenidate utility upon individual attentional domains in larger and more representative ABI samples.

Multimodal neurocognitive markers of frontal lobe epilepsy: Insights from ecological text processing

The pressing call to detect sensitive cognitive markers of frontal lobe epilepsy (FLE) remains poorly addressed. Standard frameworks prove nosologically unspecific (as they reveal deficits that also emerge across other epilepsy subtypes), possess low ecological validity, and are rarely supported by multimodal neuroimaging assessments. To bridge these gaps, we examined naturalistic action and non-action text comprehension, combined with structural and functional connectivity measures, in 19 FLE patients, 19 healthy controls, and 20 posterior cortex epilepsy (PCE) patients. Our analyses integrated inferential statistics and data-driven machine-learning classifiers. FLE patients were selectively and specifically impaired in action comprehension, irrespective of their neuropsychological profile. These deficits selectively and specifically correlated with (a) reduced integrity of the anterior thalamic radiation, a subcortical structure underlying motoric and action-language processing as well as epileptic seizure spread in this subtype; and (b) hypoconnectivity between the primary motor cortex and the left-parietal/supramarginal regions, two putative substrates of action-language comprehension. Moreover, machine-learning classifiers based on the above neurocognitive measures yielded 75% accuracy rates in discriminating individual FLE patients from both controls and PCE patients. Briefly, action-text assessments, combined with structural and functional connectivity measures, seem to capture ecological cognitive deficits that are specific to FLE, opening new avenues for discriminatory characterizations among epilepsy types.

Cognitive and behavioral profiles of pediatric surgical candidates with frontal and temporal lobe epilepsy

BACKGROUND

We aimed to prospectively analyze memory and executive and social cognitive functioning in patients with drug-resistant frontal lobe epilepsy (FLE) and temporal lobe epilepsy (TLE) with focal lesions and isolate the impact of intellectual ability on specific deficits.

METHODS

A neuropsychological evaluation was performed in 23 children with FLE, 22 children with TLE, and 36 healthy pediatric controls (HCs). Patients in the epilepsy groups had a range of lesions, including low-grade epilepsy-associated tumors (LEAT), focal cortical dysplasia (FCD) type II, and mesial temporal sclerosis (MS).

RESULTS

There were no significant differences between children with FLE and TLE regarding memory, executive, or social cognitive functioning. General Ability Index (GAI) was a predictor of memory, executive function, and social cognition scores and was influenced by age at onset, duration of epilepsy, and number of antiepileptic drugs (AEDs) prescribed at the time of assessment. Working Memory Index scores of patients with TLE, which measure verbal mnesic processing, were significantly lower than those of HCs and patients with TLE. The greatest differences in both clinical groups compared to HCs were recorded in cognitive executive functions, and patients with FLE had lower scores in this domain. Regarding behavioral executive functions, patients with TLE presented impaired emotional control and impulse inhibition and patients with FLE exhibited decreased flexibility.

CONCLUSION

Consistent with previous research, our findings provide further detailed evidence of small differences in cognitive performance among children with FLE and TLE. These differences emerge on analysis of the factors with which deficits are associated.

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.

Memory dysfunctions

Since the seminal work on the patient HM, who in his adulthood presented an acquired amnesic syndrome following the resection of the bilateral temporal lobe, other research has described several cases of isolated memory dysfunction in children. This chapter presents developmental and long-lasting memory disorders emerging from an organic or neurologic cause at birth or in infancy. More notably, we focus on developmental amnesic syndrome caused by neonatal bihippocampal damage and memory dysfunction caused by medial temporal developmental epilepsy. We describe these two pediatric populations and present the consequences of hippocampal/medial temporal lobe damage in the development of memory systems. We review episodic memory deficits in children with developmental amnesia and temporal lobe epilepsy and highlight their impact on new learning, personal memories, and independent life. Finally, we provide a brief overview of some of the insights and debates emerging from classic work and recent advances in the context of episodic memory dysfunction displayed by children with hippocampal/medial temporal lobe amnesia and propose new perspectives in child neuropsychology of memory, suggesting new avenues for more ecologic memory assessment and rehabilitation.

Neuroimaging of memory in frontal lobe epilepsy

In a large percentage of epilepsies, seizures have focal onset. These epilepsies are associated with a wide range of behavioral and cognitive deficits sometimes limited to the functions encompassed within the ictal onset zone but, more frequently, expanding beyond it. The presence of impairments associated with neuroanatomical areas outside of the ictal onset zone suggests distal propagation of epileptic activity via brain networks and interconnected whole-brain neural circuitry. In patients with frontal lobe epilepsy (FLE), using functional magnetic resonance imaging (fMRI) to identify deficits in working, semantic, and episodic memory may provide a lens through which to understand typical and atypical network organization. A network approach to focal epilepsy is relevant in these patients because of the frequently noted early age of seizure onset. Early seizure-related disruption in healthy brain development may result in a significant brain reorganization, development of compensation-related mechanisms of dealing with function abnormalities and disruptions, and the propagation of epileptic activity from the focus to widespread brain areas (functional deficit zones). Benefits of a network approach in the study of focal epilepsy are discussed along with considerations for future neuroimaging studies of patients with FLE.

Cognitive control deficits in pediatric frontal lobe epilepsy

Executive dysfunction and behavioral problems are common in children with epilepsy. Inhibition and shifting, both aspects of cognitive control, seem related to behavior problems and are thought to be driven mainly by the frontal lobes. We investigated if inhibition and shifting deficits are present in children with frontal lobe epilepsy (FLE). Secondly, we studied the relationship between these deficits and behavior problems. Thirty-one children were administered the Stroop Color Word Test and a digital version of the Wisconsin Card Sorting Test (WCST). Parents completed the Behavioral Rating Inventory for Executive Function (BRIEF) and the Achenbach scale (Child Behavior Checklist (CBCL)). About 20% of the children displayed significant low results on the Stroop Effect. About 60% showed shifting problems on the WCST. Parents reported cognitive control and behavioral deficits in about a third of the children. Also, behavioral problems and deficits in inhibition and shifting in daily life (BRIEF) seem to be related. There were no correlations between questionnaires and the Stroop and the WCST. Only in the group of children with many perseverative errors there were especially high correlations between Inhibit of the BRIEF.

Social cognition and psychopathology in childhood and adolescence

There is a substantial body of research on social cognition in adults with epilepsy, and in broad categories such as focal and generalized epilepsies, but much less has been written about social cognition in children with epilepsy (CWE), and in childhood-onset epilepsy syndromes specifically. In several of these syndromes, autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD), two disorders with social cognitive impairments, are reported. There is strong evidence for social cognitive deficits in juvenile myoclonic epilepsy (JME). There is also a considerable amount of evidence for such deficits in a number of syndromes that may be associated with ASD or ADHD, including West syndrome (WS), Dravet syndrome (DS), and the Landau-Kleffner syndrome (LKS). However, the evidence is of variable quality and incomplete across the range of childhood epilepsy syndromes. In some syndromes, childhood epilepsy substantially increases the risk of severe social cognitive impairment, which may persist after the seizures remit. This paper presents an overview of current research on social cognition in childhood epilepsy, with a particular focus on syndromes with a high prevalence of autistic and behavioral comorbidities. Social cognitive impairments represent a considerable additional challenge for patients and caregivers. Early diagnosis and intervention might significantly improve long-term social cognitive outcomes, highlighting the need for greater awareness among clinicians of this important topic. This article is part of the Special Issue "Epilepsy and social cognition across the lifespan".

Are frontal and temporal lobe epilepsy dissociable in their memory functioning?

There is controversy in the literature as to how dissociable frontal lobe epilepsy (FLE) and temporal lobe epilepsy (TLE) are in terms of memory deficits. Some researchers have demonstrated that FLE is associated with greater executive dysfunction including working memory, whereas TLE is associated with greater memory impairment. Others have found the two groups to be comparable in memory functioning. Hence, we examined this question in children with FLE and TLE versus typically developing controls. We found most of the expected effects when the groups with focal onset epilepsy were compared to controls. Specifically, children with left TLE performed worse on verbal short-term memory/learning and long-term memory measures. In contrast, children with right TLE exhibited a more global pattern of difficulty on short-term memory/learning measures but performed worse than controls on long-term memory for faces. Children with FLE performed worse than controls on verbal working memory. Nevertheless, laterality effects were mild, as children with right and left TLE did not differ significantly from each other. Further, children with FLE did not differ from those with TLE on most measures except delayed facial recognition, where children with right TLE performed worse. In addition, attention problems and poor behavioral regulation were related to encoding problems in both the total epilepsy sample and in children with TLE specifically. Hence, our findings overall are consistent with prior studies indicating that children with TLE and FLE are commensurate in most aspects of memory impairment when compared to each other, likely related to rapid propagation between the frontal and temporal lobes, as would be expected with an excitatory lesion.

Behaviour outcomes in children with epilepsy 1 year after surgical resection of the ventromedial prefrontal cortex

Early damage to the ventromedial prefrontal cortex (VM) has been associated with impaired behavioural functioning in children without epilepsy, yet behaviour in children with epilepsy and VM lesions has not been investigated. The primary aim of this study was to examine behavioural outcomes in children with epilepsy emanating from the VM preoperatively and one year after epilepsy surgery compared to the general population and matched epilepsy controls. Behavioural outcomes were defined as comprising both problems and competencies (i.e. social, school and co-curricular performance). A secondary aim was to examine whether seizure outcome, number of antiepileptic drugs (AEDs), or age at surgery related to behavioural outcomes. Ratings on the Child Behavior Checklist were examined preoperatively and 1 year after surgery for 20 children with epilepsy who had undergone surgical resection of the VM (N = 10) or temporal lobe (TL, N = 10). VM and TL groups were comparable on Full Scale IQ (40-101), age of seizure onset (0.5-9.0 years), age at surgery (3.1-16.9 years), seizure laterality (5 left in each group), age at assessments, sex (3 female in VM group, 2 female in TL group) and seizure outcome (7 seizure free in VM group, 6 seizure free in TL group). The VM group had significantly elevated behaviour problems (i.e. withdrawn, thought, social and attention problems) and reduced competencies (i.e. social and school) compared to the general population before and after surgery. VM and TL cases did not differ on any behaviour problem scales pre or postoperatively and neither group showed significant change in functioning over time; however, VM patients had significantly lower total competence than TL patients postoperatively. A significant seizure outcome × time interaction was observed: children who were seizure free following surgery (collapsed across surgical site) showed an improvement in total behaviour problems and aggression at 1 year follow-up, whereas children with ongoing seizures showed a deterioration in these domains. In conclusion, VM lesions in children with epilepsy are associated with behavioural problems but their profile does not differ from that of children with temporal lobe epilepsy. These results are consistent with the concept that seizures arise from epileptogenic networks that may affect multiple cortical areas, even when onset is in a focal site.

The burden of parenting children with frontal lobe epilepsy

OBJECTIVE

Caring for a child with a chronic illness adds stress to the typical parenting stress in healthy developing children. This stress can place a heavy burden on parents and may increase when a child displays problem behavior. In general, parenting and child's behavior problems are associated. Furthermore, externalizing (more outgoing) behavior is reported frequently in children with frontal lobe epilepsy (FLE). Therefore, in this study, we first investigated the burden of parents of children with FLE, and second, we investigated the relation between the experienced burden and reported behavioral problems. The validity of parents' reports on proxy measures as well as duration of epilepsy is taken into account.

METHODS

Thirty-one parents of children with FLE completed validated questionnaires about behavioral problems and burden of parenting. To examine if parents tend to be inconsistent or unusually negative, we used the two validity scales of the Behavioral Rating Inventory of Executive Function (BRIEF) (Negativity and Inconsistency).

RESULTS

Only parents of children with FLE who have had epilepsy for 5 years or longer report more problems on the Nijmeegse Vragenlijst voor de Opvoedingssituatie (NVOS) subscales 'Able to manage', 'Child is a burden', and 'Good Interaction' compared with the healthy controls. The subscale 'Child is a burden' significantly predicts scores in about 20% to 49% on the main scales of the Child Behavior Checklist (CBCL), the Global Executive Composite (GEC), and Behavioral Regulation Index (BRI) of the BRIEF. Only 6% of parents scored in the clinical range of the negativity scale of the BRIEF. For the inconsistency scale, this was 45%.

CONCLUSION

Parents of children with FLE do not report excessive parental burden. Longer duration of epilepsy might be a risk factor in experiencing burden. The findings suggest a link between parental burden and behavioral problems in children with FLE. Externalizing behavioral problems are the most marked behavioral problems, which relate to the parental burden. Parents tend to be inconsistent in their ratings.

Working memory in pediatric frontal lobe epilepsy

Thirty-two children with frontal lobe epilepsy (FLE) were assessed using different working memory measures. In addition, parents and teachers completed the working memory scale of the Behavioral Rating Inventory of Executive Functioning (BRIEF) to assess the children's "daily life behavior." Results suggested minimal working memory deficits as assessed with performance-based measures. However, the BRIEF showed more working memory deficits suggesting that, on a daily life level, working memory problems seem to be associated with FLE. We discuss why the results of the performance-based measures are not consistent with results of the BRIEF.HighlightsParents as well as teachers report working memory dysfunction in daily life to the same extent.Performance based measures show minimal deficits of working memory.Correlation between working memory tasks and proxy measures are low.

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.

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.

Neuropsychology of frontal lobe epilepsy in children and adults: Systematic review and meta-analysis

Frontal lobe epilepsy (FLE) is associated with cognitive problems, especially in areas related to frontal lobe functioning as executive functions, attention, and motor skills, but with impact on memory and psychosocial adaptation. Deficits are similar in both adults and children with FLE, although no studies have compared adult and pediatric performance in the same study. The aim of this research was to analyze the existing evidence concerning the cognition in adults and children with FLE. A random effect meta-analysis was used using Cohen's d, and the confidence interval for each cognitive factor was calculated. The results in the meta-analysis show a general pattern of cognitive dysfunction in FLE, especially in functions related to the frontal lobe, with an influence of the duration and the age at onset of epilepsy, as well as the age of the sample used. In addition, researches in this type of epilepsy are heterogeneous, with too many different sampling and methodological characteristics, which is not a standard format for reporting clinical sample characterization, making it difficult to study FLE in depth.

Executive and behavioral functioning in pediatric frontal lobe epilepsy

OBJECTIVE

Epilepsy, as a chronic and neurological disease, is generally associated with an increased risk for social and emotional behavior problems in children. These findings are mostly derived from studies on children with different epilepsy types. However, there is limited information about the associations between frontal lobe epilepsy (FLE) and cognitive and behavioral problems. The aim of this study was to examine relationships between FLE and executive and behavioral functioning reported by parents and teachers.

MATERIAL AND METHODS

Teachers and parents of 32 children (18 boys, 14 girls, mean age 9; 2 years ±1;6) with a confirmed diagnosis of FLE completed the Behavioral Rating Inventory of Executive Function (BRIEF), the Child Behavior Checklist (CBCL), and Teacher Report Form (TRF).

RESULTS

About 25 to 35% of the parents and teachers rated children in the abnormal range of the main scales of the BRIEF, CBCL, and TRF. Teachers tend to report more metacognition problems, whereas parents tend to report more behavior regulation problems. Children with left-sided FLE showed more problems than children with bilateral or right-sided FLE. The whole range of executive dysfunctioning is linked to behavioral dysfunctioning in FLE, but ratings vary across settings and informants. The epilepsy variables age of onset, lateralization, drug load, and duration of epilepsy had only a small and scattered contribution.

CONCLUSION

Ratings on the BRIEF, CBCL, and TRF are moderately to highly correlated, suggesting a (strong) link between executive and behavioral functioning. Subtle differences between parents and teachers ratings suggest different executive function demands in various settings.

Thalamocortical Connections and Executive Function in Pediatric Temporal and Frontal Lobe Epilepsy

BACKGROUND AND PURPOSE

Largely accepted in the literature is the role the interconnections between the thalamus and cortex play in generalized epilepsy. However, thalamocortical involvement is less understood in focal epilepsy in terms of the effect of seizures on thalamocortical circuitry in the developing brain and subsequent cognitive outcome. We investigated thalamocortical pathway microstructure in pediatric frontal lobe epilepsy and temporal lobe epilepsy and examined the associations between pathway microstructure and measures of executive function.

MATERIALS AND METHODS

We examined thalamocortical connections in 24 children with frontal lobe epilepsy, 17 patients with temporal lobe epilepsy, and 25 healthy children using DTI. We investigated several executive function measures in patients and controls, which were distilled into latent executive function components to compare among groups, and the associations between measures of thalamocortical microstructure and executive function.

RESULTS

We found no differences in thalamocortical pathway microstructure between the groups, but aspects of executive function (mental flexibility/inhibition/shifting) were impaired in the frontal lobe epilepsy group compared with controls. In patients with frontal lobe epilepsy, younger age at seizure onset and a greater number of antiepileptic drugs were associated with DTI indices indicative of damaged/less developed thalamocortical pathways. In patients with temporal lobe epilepsy, poorer performance on all measures of executive function was associated with DTI indices reflective of damaged/less developed pathways.

CONCLUSIONS

Our results give insight into vulnerable neural networks in pediatric focal epilepsy and suggest thalamocortical pathway damage as a potential mechanism of executive function impairment in temporal lobe epilepsy but not frontal lobe epilepsy. Identifying structure-function relations can help inform how we measure functional and cognitive/behavioral outcomes in these populations.

Unique and shared areas of cognitive function in children with intractable frontal or temporal lobe epilepsy

OBJECTIVE

Previous findings have been mixed in terms of identifying a distinct pattern of neuropsychological deficits in children with frontal lobe epilepsy (FLE) and in those with temporal lobe epilepsy (TLE). The current study investigated the neuropsychological similarities and differences across these two pediatric medically intractable localization-related epilepsies.

METHOD

Thirty-eight children with FLE, 20 children with TLE, and 40 healthy children (HC) participated in this study. A comprehensive battery of standardized tests assessed five neuropsychological domains including intelligence, language, memory, executive function, and motor function. A principal component analysis (PCA) was used to distill our neuropsychological measures into latent components to compare between groups.

RESULTS

Principal component analysis extracted 5 latent components: executive function (F1), verbal semantics (F2), motor (F3), nonverbal cognition/impulsivity (F4), and verbal cognition/attention (F5). The group with FLE differed from the HC group on F1, F2, F4, and F5, and had worse performance than the group with TLE on F1; the group with TLE had lower performance relative to the HC group on F2.

CONCLUSION

Our findings suggest that, in comparison with neurotypically developing children, children with medically intractable FLE have more widespread neuropsychological impairments than do children with TLE. The differences between the two patient groups were greatest for the factor score most clearly related to executive function. The results provide mixed support for the concept of specificity in neuropsychological dysfunction among different subtypes of localization-related medically intractable childhood epilepsies.

Attention Deficit Hyperactivity Disorder and Associated Cognitive Dysfunction in Pediatric Epilepsy

Attention deficit hyperactivity disorder (ADHD) is the most common neuropsychiatric comorbidity associated with childhood epilepsy, affecting about a third of children with epilepsy. In contrast, ADHD in the general population occurs in 4%-12% of school-aged children. The cause of this association remains unclear. It is likely that common mechanisms underlie the vulnerability for both executive deficits and epileptogenesis. There are characteristics unique to children with ADHD and epilepsy. The inattentive type of ADHD is more prevalent than the combined presentation in children with epilepsy, while the combined type is more common in the general population. Interestingly, there is an equal sex distribution of ADHD in patients with epilepsy, while in the general population, ADHD is 3-7 times more prevalent in boys. Specific features of ADHD seen in different epilepsy syndromes are frequently associated with executive deficits. Early screening of ADHD symptoms in children with epilepsy is essential, as timely interventions can improve academic and social function and outcomes. The mainstays of therapy include behavioral interventions and pharmacotherapy, with evidence demonstrating that stimulants are both safe and effective in children with ADHD and epilepsy.

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.

Considerations for ADHD in the child with epilepsy and the child with migraine

INTRODUCTION

Attention Deficit Hyperactivity Disorder (ADHD) is a common comorbid condition in children with epilepsy and migraine. Treatment of ADHD in children with epilepsy or migraine is essential but clinicians may overlook symptoms of ADHD and avoid appropriate use of medications that may reduce symptoms of ADHD without compromising treatment of epilepsy or migraine. Areas covered: PubMed was searched for articles on ADHD and epilepsy or migraine. Key papers were reviewed for additional articles. Areas of interest were: epidemiology, etiological factors, and treatment with emphasis on therapy. Expert commentary: Stimulant medication, especially methylphenidate, appears to be safe and effective in the treatment of ADHD in children with epilepsy or migraine. Unfortunately, data is limited with very few controlled trials of methylphenidate and very limited information on the use of amphetamines or non-stimulant drugs.

The executive profile of children with Benign Epilepsy of Childhood with Centrotemporal Spikes and Temporal Lobe Epilepsy

RATIONALE

Benign Epilepsy of Childhood with Centrotemporal Spikes (BECTS) and temporal lobe epilepsy (TLE) represent two distinct models of focal epilepsy of childhood. In both, there is evidence of executive dysfunction. The purpose of the present study was to identify particular deficits in the executive function that would distinguish children with BECTS from children with TLE.

METHODS

We prospectively evaluated 19 consecutive children and adolescents with TLE with hippocampal sclerosis (HS) (57.9% male; mean 11.74years [SD 2.05]; mean IQ 95.21 [SD 15.09]), 19 with BECTS (36.8% male; mean 10.95years [SD 2.33]; mean IQ 107.40 [SD 16.01]), and 21 age and gender-matched controls (33.3% male; mean 11.86years [SD 2.25]; mean IQ 108.67 [15.05]). All participants underwent a neuropsychological assessment with a comprehensive battery for executive and attentional functions. We used ANOVA and chi-square to evaluate differences on demographic aspects among groups (BECTS, TLE-HS, and control groups). Group comparisons on continuous variables were complemented by MANOVA and Bonferroni posthoc comparisons.

RESULTS

Patients with BECTS had worse performance than controls in: Matching Familiar Figures Test, time (p=0.001); Matching Familiar Figures Test, time×errors index (p<0.001); Verbal Fluency for foods (p=0.038); Trail Making Test, part B time (p=0.030); Trail Making Test, part B number of errors (p=0.030); and WCST, number of categories achieved (p=0.043). Patients with BECTS had worse performance than patients with TLE-HS on Matching Familiar Figures Test, time (p=0.004), and Matching Familiar Figures Test, time×errors index (p<0.001). Patients with TLE-HS had worse performance than controls on the following tests: Verbal Fluency for foods (p=0.004); Wisconsin Card Sorting Test, the number of categories achieved (p<0.001); and Wisconsin Card Sorting Test, the number of perseverative errors (p=0.028). Patients with TLE-HS had worse performance than patients with BECTS on Digit Backward (p=0.002); and the Wisconsin Card Sorting Test, the number of perseverative errors (p<0.001).

CONCLUSIONS

Patients with TLE and BECTS present distinct cognitive profiles. Patients with TLE-HS had worse performance in mental flexibility, concept formation, and working memory compared to BECTS. Patients with BECTS had worse inhibitory control compared to children with TLE-HS. Both TLE-HS and BECTS had a higher number of errors on an inhibitory control test. However, patients with BECTS had a slower mental processing even when compared to patients with TLE-HS. Rehabilitation programs for children with epilepsy must include children with benign epilepsies and must take into account the epileptic syndrome and its particular neurocognitive phenotype.

Rethinking cognition and behavior in the new classification for childhood epilepsy: Examples from frontal lobe and temporal lobe epilepsies

The new approach to classification of the epilepsies emphasizes the role of dysfunction in networks in defining types of epilepsies. This paper reviews the structural and neuropsychological deficits in two types of childhood epilepsy: frontal lobe and temporal lobe epilepsy. The evidence for and against a pattern of specificity of deficits in executive function and memory associated with these two types of epilepsies is presented. The evidence varies with the methodologies used in the studies, but direct comparison of the two types of epilepsies does not suggest a clear-cut mapping of function onto structure. These findings are discussed in light of the concept of network dysfunction. The evidence supports the conceptualization of epilepsy as a network disease. Implications for future work in the neuropsychology of pediatric epilepsy are suggested. This article is part of a Special Issue entitled "The new approach to classification: Rethinking cognition and behavior in epilepsy".

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.

Rey-Osterrieth Complex Figure - copy and immediate recall: Normative data for the Latin American Spanish speaking adult population

OBJECTIVE

To generate normative data on the Rey-Osterrieth Complex Figure Test (ROCF) across 11 countries in Latin America, with country-specific adjustments for gender, age, and education, where appropriate.

METHOD

The sample consisted of 3,977 healthy adults who were recruited from Argentina, Bolivia, Chile, Cuba, El Salvador, Guatemala, Honduras, Mexico, Paraguay, Peru, and, Puerto Rico. Each subject was administered the ROCF as part of a larger neuropsychological battery. A standardized five-step statistical procedure was used to generate the norms.

RESULTS

The final multiple linear regression models explained 7-34% of the variance in ROCF copy scores and 21-41% of the variance in immediate recall scores. Although t-tests showed significant differences between men and women on ROCF copy and immediate recall scores, none of the countries had an effect size larger than 0.3. As a result, gender-adjusted norms were not generated.

CONCLUSIONS

The present study is the first to create norms for the ROCF in Latin America. As a result, this study will have important implications for the formation and practice of neuropsychology in this region.

Cognitive and neurodevelopmental comorbidities in paediatric epilepsy

Cognitive and behavioural comorbidities are often seen in children with epilepsy, and are more common and severe in refractory epilepsy. These comorbidities are associated with worse quality of life, increased behavioural and language problems and worse social skills, all of which adversely affect long-term psychosocial functioning. To enable early intervention and therapy, children and teens with epilepsy should be periodically screened for cognitive comorbidities. The location of the epileptic focus can, to a certain degree, predict the type(s) of comorbidity; however, the spectrum of disability is often broad, presumably because focal perturbations can cause network dysfunction. Comorbidities often result from underlying structural or functional pathology that has led to seizures. In selected cases, therapy targeting the underlying cause, such as the ketogenic diet for GLUT1 deficiency syndromes, may be remarkably effective in ameliorating both seizures and cognitive concerns. In many cases, however, cognitive impairment persists despite seizure control. In epileptic encephalopathies, frequent seizures and/or interictal epileptiform abnormalities exacerbate neurocognitive dysfunction, owing to synaptic reorganization or impaired neurogenesis, or to other effects on developing neural circuits, and prompt initiation of effective antiepileptic therapy is essential to limit cognitive comorbidities.

Children with well controlled epilepsy possess different spatio-temporal patterns of causal network connectivity during a visual working memory task

Using spectral Granger causality (GC) we identified distinct spatio-temporal causal connectivity (CC) patterns in groups of control and epileptic children during the execution of a one-back matching visual discrimination working memory task. Differences between control and epileptic groups were determined for both GO and NOGO conditions. The analysis was performed on a set of 19-channel EEG cortical activity signals. We show that for the GO task, the highest brain activity in terms of the density of the CC networks is observed in α band for the control group while for the epileptic group the CC network seems disrupted as reflected by the small number of connections. For the NOGO task, the denser CC network was observed in θ band for the control group while widespread differences between the control and the epileptic group were located bilaterally at the left temporal-midline and parietal areas. In order to test the discriminative power of our analysis, we performed a pattern analysis approach based on fuzzy classification techniques. The performance of the classification scheme was evaluated using permutation tests. The analysis demonstrated that, on average, 87.6 % of the subjects were correctly classified in control and epileptic. Thus, our findings may provide a helpful insight on the mechanisms pertaining to the cognitive response of children with well controlled epilepsy and could potentially serve as "functional" biomarkers for early diagnosis.

Neuropsychological profiles and outcomes in children with new onset frontal lobe epilepsy

Frontal lobe epilepsy (FLE) is the second most frequent type of localization-related epilepsy, and it may impact neurocognitive functioning with high variability. The prevalence of neurocognitive impairment in affected children remains poorly defined. This report outlines the neuropsychological profiles and outcomes in children with new onset FLE, and the impact of epilepsy-related factors, such as seizure frequency and antiepileptic drug (AED) load, on the neurocognitive development. Twenty-three consecutive children (15 males and 8 females) with newly diagnosed cryptogenic FLE were enrolled; median age at epilepsy onset was 7 years (6-9.6 years). They underwent clinical and laboratory evaluation and neuropsychological assessment before starting AED treatment (time 0) and after one year of treatment (time 1). Twenty age-matched patients affected by idiopathic generalized epilepsy (10 male and 10 females) and eighteen age-matched healthy subjects (9 males and 9 females) were enrolled as controls and underwent the same assessment. All patients with FLE showed a significant difference in almost all assessed cognitive domains compared with controls, mainly in frontal functions and memory. At time 1, patients were divided into two groups according to epilepsy-related factors: group 1 (9 patients) with persisting seizures despite AED polytherapy, and group 2 (14 patients) with good seizure control in monotherapy. A significant difference was highlighted in almost all subtests in group 1 compared with group 2, both at time 0 and at time 1. In children with FLE showing a broad range of neurocognitive impairments, the epilepsy-related factors mostly related to a worse neurocognitive outcome are poor seizure control and the use of AED polytherapy, suggesting that epileptic discharges may have a negative impact on the functioning of the involved cerebral regions.

Epilepsy and attention-deficit hyperactivity disorder: links, risks, and challenges

Attention-deficit hyperactivity disorder (ADHD) has a prevalence rate of 7%-9% in the general population of children. However, in children with epilepsy, ADHD has been found to be present in 20%-50% of patients. This paper provides a review of ADHD prevalence in pediatric epilepsy populations and reviews data on specific symptom presentation and attention deficits in patients with epilepsy. This paper also reviews evidence-based treatments for ADHD and specifically the treatment of ADHD as a comorbid condition in children with epilepsy.

Patterns of verbal learning and memory in children with intractable temporal lobe or frontal lobe epilepsy

PURPOSE

The objective of this study was to provide a better understanding of the verbal learning and memory (VLM) patterns that might differentiate children with frontal lobe epilepsy (FLE) from children with temporal lobe epilepsy (TLE) and to examine the impact of variables thought to influence outcomes (seizure laterality, age at seizure onset, age at assessment, epilepsy duration, number of antiepileptic drugs).

METHODS

Retrospective analyses were carried out for children with intractable unilateral TLE (n=100) and FLE (n=27) who completed standardized measures of VLM entailing lists of single words or lists of word pairs.

RESULTS

Mean intelligent quotients and VLM scores on single words fell within the average range for both groups, whereas scores fell within the low average to borderline range on word pairs. No significant overall differences in VLM were found between the group with TLE and the group with FLE. Older age at assessment and older age at seizure onset were generally associated with better VLM in both groups but were related to better performance in a number of indices in the group with TLE and only fewer intrusions in the group with FLE.

CONCLUSIONS

The VLM profiles of children with TLE and FLE are generally similar. Older age at assessment and older age at seizure onset have a favorable impact on both groups but are related to better encoding, retrieval, and monitoring processes for the group with TLE and improved memory monitoring (i.e., as indicated by fewer intrusions) in the group with FLE.

Statistical parametric mapping for analyzing interictal magnetoencephalography in patients with left frontal lobe epilepsy

PURPOSE

Frontal lobe epilepsy is a common epileptic disorder and is characterized by recurring seizures that arise in the frontal lobes. The purpose of this study is to identify the epileptogenic regions and other abnormal regions in patients with left frontal lobe epilepsy (LFLE) based on the magnetoencephalogram (MEG), and to understand the effects of clinical variables on brain activities in patients with LFLE.

METHOD

Fifteen patients with LFLE (23.20 ± 8.68 years, 6 female and 9 male) and 16 healthy controls (23.13 ± 7.66 years, 6 female and 10 male) were included in resting-stage MEG examinations. Epileptogenic regions of LFLE patients were confirmed by surgery. Regional brain activations were quantified using statistical parametric mapping (SPM). The correlation between the activations of the abnormal brain regions and the clinical seizure parameters were computed for LFLE patients.

RESULTS

Brain activations of LFLE patients were significantly elevated in left superior/middle/inferior frontal gyri, postcentral gyrus, inferior temporal gyrus, insula, parahippocampal gyrus and amygdala, including the epileptogenic regions. Remarkable decreased activations were found mainly in the left parietal gyrus and precuneus. There is a positive correlation between the duration of the epilepsy (in month) and activations of the abnormal regions, while no relation was found between age of seizure onset (year), seizure frequency and the regions of the abnormal activity of the epileptic patients.

CONCLUSION

Our findings suggest that the aberrant brain activities of LFLE patients were not restricted to the epileptogenic zones. Long duration of epilepsy might induce further functional damage in patients with LFLE.

[Formula: see text]Differences in memory functioning between children with attention-deficit/hyperactivity disorder and/or focal epilepsy

Prior research has shown that attention-deficit/hyperactivity disorder (ADHD) and epilepsy are frequently comorbid and that both disorders are associated with various attention and memory problems. Nonetheless, limited research has been conducted comparing the two disorders in one sample to determine unique versus shared deficits. Hence, we investigated differences in working memory (WM) and short-term and delayed recall between children with ADHD, focal epilepsy of mixed foci, comorbid ADHD/epilepsy and controls. Participants were compared on the Core subtests and the Picture Locations subtest of the Children's Memory Scale (CMS). Results indicated that children with ADHD displayed intact verbal WM and long-term memory (LTM), as well as intact performance on most aspects of short-term memory (STM). They performed worse than controls on Numbers Forward and Picture Locations, suggesting problems with focused attention and simple span for visual-spatial material. Conversely, children with epilepsy displayed poor focused attention and STM regardless of the modality assessed, which affected encoding into LTM. The only loss over time was found for passages (Stories). WM was intact. Children with comorbid ADHD/epilepsy displayed focused attention and STM/LTM problems consistent with both disorders, having the lowest scores across the four groups. Hence, focused attention and visual-spatial span appear to be affected in both disorders, whereas additional STM/encoding problems are specific to epilepsy. Children with comorbid ADHD/epilepsy have deficits consistent with both disorders, with slight additive effects. This study suggests that attention and memory testing should be a regular part of the evaluation of children with epilepsy and ADHD.

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.

Social competence among well-functioning adolescents with epilepsy

PURPOSE

The aims of the study were to measure the social competence of well-functioning adolescents with epilepsy and compare it with that of their healthy peers as well as to analyze the effects of epilepsy-related variables on the social competence.

METHODS

Ninety well-functioning adolescents with epilepsy 12-19years of age were compared with healthy controls using the Achenbach Youth Self-Report Questionnaire measures of social competence. Within the group with epilepsy, the impact of duration of epilepsy, etiology, seizure frequency, seizure type, and antiepileptic drugs (AEDs) (monotherapy or polytherapy) on the above measures was also determined.

RESULTS

Twenty-five (27.8%) adolescents with epilepsy obtained Total Competence T scores in the clinical range, as opposed to only two (3.3%) of the healthy adolescents. There were statistically significant differences in the Activity and Social subscales and Total Competence T score between the group with epilepsy and the control group (p<0.05). Comparing T scores for epilepsy-related variables in the group with epilepsy, we found that there were statistically significant differences in all the social competence subscales regarding the seizure control and seizure types. No significant differences were obtained for other epilepsy-related variables: duration of epilepsy, onset of epilepsy, etiology, and AEDs.

CONCLUSION

Our results indicate that adolescents with epilepsy are less active in clubs, socialize less with their friends, and have a poorer school performance compared with their healthy peers. This study shows that adolescents with epilepsy are at an increased risk of having difficulties in social competence.

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.

Assessment of everyday executive functioning in children with frontal or temporal epilepsies

Executive functions are particularly vulnerable in case of brain disruption during childhood, when the brain is not fully mature. Some studies showed impairments of executive functions in children with epilepsy, but only a few of them investigated the impact of executive dysfunctions on daily life. The aim of this study was to understand the everyday executive functioning of children with epilepsy both at home and in school. We administered the Behavior Rating Inventory of Executive Function to parents and teachers of 53 children (7-16 years of age) with structural epilepsies or epilepsies of unknown cause of temporal lobe (n=25) or frontal lobe (n=28). The results indicated a global executive impairment in the whole group of patients, compared with normative data, with no difference between the group with temporal lobe epilepsy (TLE) and that with frontal lobe epilepsy (FLE), except for monitor domain, which seemed more frequently impaired in the group with FLE. Congruence between parent and teacher ratings was found. The frequency of seizures was not related to executive dysfunction, whereas the number of antiepileptic drugs tended to positively correlate with working memory impairment. Onset of epilepsy at a younger age was also related to more executive difficulties but only according to teacher ratings. Lastly, duration of epilepsy was strongly associated with executive deficits reported in the context of school. Our results support the executive dysfunction hypothesis in daily life of children with structural focal epilepsy or focal epilepsy of unknown cause and are consistent with the early brain vulnerability hypothesis currently prevalent in the context of child neuropsychology. The BRIEF appears to be a clinically useful tool for assessing executive function impairment in this clinical population.

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.

Patient considerations in the management of focal seizures in children and adolescents

Focal epilepsy accounts for approximately one-half to two-thirds of new-onset epilepsy in children. Etiologies are diverse, and range from benign epilepsy syndromes with normal neuroimaging and almost certain remission to focal malformations of cortical development or hippocampal sclerosis with intractable seizures persisting lifelong. Other important etiologies in children include pre-, peri-, or postnatal brain injury, low-grade neoplasms, vascular lesions, and neuroimmunological disorders. Cognitive, behavioral, and psychiatric comorbidities are commonly seen and must be addressed in addition to seizure control. Given the diverse nature of focal epilepsies in children and adolescents, investigations and treatments must be individualized. First-line therapy consists of prophylactic antiepileptic drugs; however, prognosis is poor after failure of two to three drugs for lack of efficacy. Refractory cases should be referred for an epilepsy surgery workup. Dietary treatments and neurostimulation may be considered in refractory cases who are not good candidates for surgery.

Cognition, academic achievement, and epilepsy in school-age children: a case-control study in a developing country

We conducted a case-control study of 33 Jamaican children 7 to 12years old with uncomplicated epilepsy and 33 of their classroom peers matched for age and gender to determine whether epilepsy resulted in differences in cognitive ability and school achievement and if socioeconomic status or the environment had a moderating effect on any differences. Intelligence, language, memory, attention, executive function, and mathematics ability were assessed using selected tests from NEPSY, WISCR, TeaCh, WRAT3 - expanded, and Raven's Coloured Progressive Matrices. The child's environment at home was measured using the Middle Childhood HOME inventory. Socioeconomic status was determined from a combination of household, crowding, possessions, and sanitation. We compared the characteristics of the cases and controls and used random effects regression models (using the matched pair as the cluster) to examine the relationship between cognition and epilepsy. We found that there was no significant difference in IQ, but children with epilepsy had lower scores on tests of memory (p<0.05), language (p<0.05), and attention (p<0.01) compared with their controls. In random effects models, epilepsy status had a significant effect on memory (coefficient=-0.14, CI: -0.23, -0.05), language (coefficient=-0.13, CI: -0.23, -0.04), and mathematics ability (coefficient=-0.01, CI: -0.02, -0.00). Adjustment for the home environment and socioeconomic status and inclusion of interaction terms for these variables did not alter these effects. In conclusion, we found that epilepsy status in Jamaican children has a significant effect on performance on tests of memory, language, and mathematics and that this effect is not modified or explained by socioeconomic status or the child's home environment.

Temporal lobe epilepsy in children: executive and mnestic impairments

The current definition of epilepsy emphasizes the importance of cognitive impairment for a complete understanding of the disorder. Cognitive deficits have distinct functional manifestations that differentially impact the daily life experiences of children and adolescents with epilepsy and are a particular concern as they frequently impair academic performance. In particular, memory impairment and executive dysfunction are common disabilities in adults with temporal lobe epilepsy but are less easily recognized and studied in the pediatric population. This review focuses on the consequences of early-onset temporal lobe epilepsy for the development of memory and executive function and discusses current theories to explain these deficits.

Clinical observations on attention-deficit hyperactivity disorder (ADHD) in children with frontal lobe epilepsy

The objective was to investigate the prevalence of attention-deficit hyperactivity disorder (ADHD) in children with frontal lobe epilepsy and related factors. The medical records of 190 children diagnosed with frontal lobe epilepsy at Qilu Hospital of Shandong University between 2006 and 2011 were retrospectively collected, and a follow-up analysis of the prevalence of ADHD in these children was conducted. Of the 161 children with an effective follow-up, 59.0% (95/161) with frontal lobe epilepsy suffered from ADHD as well. Analysis of epilepsy and ADHD-related factors indicated that the incidence of ADHD was 89.4% (76/85) in children with abnormal electroencephalogram (EEG) discharges on the most recent EEG, which was significantly higher than the ADHD incidence of 25% (19/76) in children with normal readings on the most recent EEG (P < .01). Children with frontal lobe epilepsy have a high incidence of ADHD. Sustained abnormal discharge on the electroencephalogram is associated with increased comorbidity of ADHD with frontal lobe epilepsy.