Neuropsychological disorders related to interictal epileptic discharges during sleep in benign epilepsy of childhood with centrotemporal or Rolandic spikes

How the Spreading and Intensity of Interictal Epileptic Activity Are Associated with Visuo-Spatial Skills in Children with Self-Limited Focal Epilepsy with Centro-Temporal Spikes

This paper investigates brain-behaviour associations between interictal epileptic discharges and cognitive performance in a population of children with self-limited focal epilepsy with centro-temporal spikes (SeLECTS). Sixteen patients with SeLECTS underwent an extensive neuropsychological assessment, including verbal short-term and episodic memory, non-verbal short-term memory, attentional abilities and executive function. Two quantitative EEG indices were analysed, i.e., the Spike Wave Index (SWI) and the Spike Wave Frequency (SWF), and one qualitative EEG index, i.e., the EEG score, was used to evaluate the spreading of focal SW to other parts of the brain. We investigated associations between EEG indices and neuropsychological performance with non-parametric Spearman correlation analyses, including correction for multiple comparisons. The results showed a significant negative correlation between (i) the awake EEG score and the Block Tapping Test, a visuo-spatial short-term memory task, and (ii) the sleep SWI and the Tower of London, a visuo-spatial planning task (pcorr < 0.05). These findings suggest that, in addition to the usual quantitative EEG indices, the EEG analysis should include the qualitative EEG score evaluating the spreading of focal SW to other parts of the brain and that neuropsychological assessment should include visuo-spatial skills.

Self-limited childhood epilepsies are disorders of the perisylvian communication system, carrying the risk of progress to epileptic encephalopathies-Critical review

"Sleep plasticity is a double-edged sword: a powerful machinery of neural build-up, with a risk to epileptic derailment." We aimed to review the types of self-limited focal epilepsies..."i.e. keep as two separate paragraphs" We aimed to review the types of self-limited focal epilepsies: (1) self-limited focal childhood epilepsy with centrotemporal spikes, (2) atypical Rolandic epilepsy, and (3) electrical status epilepticus in sleep with mental consequences, including Landau-Kleffner-type acquired aphasia, showing their spectral relationship and discussing the debated topics. Our endeavor is to support the system epilepsy concept in this group of epilepsies, using them as models for epileptogenesis in general. The spectral continuity of the involved conditions is evidenced by several features: language impairment, the overarching presence of centrotemporal spikes and ripples (with changing electromorphology across the spectrum), the essential timely and spatial independence of interictal epileptic discharges from seizures, NREM sleep relatedness, and the existence of the intermediate-severity "atypical" forms. These epilepsies might be the consequences of a genetically determined transitory developmental failure, reflected by widespread neuropsychological symptoms originating from the perisylvian network that have distinct time and space relations from secondary epilepsy itself. The involved epilepsies carry the risk of progression to severe, potentially irreversible encephalopathic forms.

Alternations of neuromagnetic activity across neurocognitive core networks among benign childhood epilepsy with centrotemporal spikes: A multi-frequency MEG study

Objective

We aimed to investigate the alternations of neuromagnetic activity across neurocognitive core networks among early untreated children having benign childhood epilepsy with centrotemporal spikes (BECTS).

Methods

We recorded the Magnetoencephalography (MEG) resting-state data from 48 untreated children having BECTS and 24 healthy children. The fourth edition of the Wechsler Intelligence Scale for Children (WISC-IV) was utilized to divide the children with BECTS into two groups: the cognitive impairment (CI) group with a full-scale intelligence quotient (FSIQ) of < 90 and the cognitive non-impairment (CNI) group with an FSIQ of > 90. We selected 26 bilateral cognitive-related regions of interest based on the triple network model. The neurocognitive core network spectral power was estimated using a minimum norm estimate (MNE).

Results

In the CNI group, the spectral power inside the bilateral anterior cingulate cortex (ACC) and the bilateral caudal middle frontal cortex (CMF) enhanced within the delta band and reduced within the alpha band. Both the CI and the CNI group demonstrated enhanced spectral power inside the bilateral posterior cingulate cortex (PCC), bilateral precuneus (PCu) region, bilateral superior and middle temporal cortex, bilateral inferior parietal lobe (IPL), and bilateral supramarginal cortex (SM) region in the delta band. Moreover, there was decreased spectral power in the alpha band. In addition, there were consistent changes in the high-frequency spectrum (> 90 Hz). The spectral power density within the insula cortex (IC), superior temporal cortex (ST), middle temporal cortex (MT), and parahippocampal cortex (PaH) also decreased. Therefore, studying high-frequency activity could lead to a new understanding of the pathogenesis of BECTS.

Conclusion

The alternations of spectral power among neurocognitive core networks could account for CI among early untreated children having BECTS. The dynamic properties of spectral power in different frequency bands could behave as biomarkers for diagnosing new BECTS.

Does epileptic activity impair sleep-related memory consolidation in epilepsy? A critical and systematic review

STUDY OBJECTIVES

People with epilepsy often complain about disturbed sleep and cognitive impairment. Beyond seizures, the occurrence of interictal epileptic activity during sleep is also increasingly recognized to negatively impact cognitive functioning, including memory processes. The aim of this study was to critically review the effect of interictal epileptic activity on sleep-related memory consolidation.

METHODS

PubMed and PsychINFO databases were systematically searched to identify experimental studies that investigated sleep-related memory consolidation and the relationships between sleep-related epileptic activity and memory in adults and children with epilepsy. This review also highlights hypotheses regarding the potential pathophysiological mechanisms.

RESULTS

A total of 261 studies were identified; 27 of these met selection criteria. Only 13 studies prospectively assessed the effect of sleep on memory in epilepsy. Most studies reported no alteration of sleep-related memory consolidation in patients, with either similar retention levels following a period containing sleep (n = 5) or improved memory performance postsleep (n = 4). Two studies in children with epilepsy found impaired sleep-related memory consolidation. Ten studies, of which 6 were in childhood epilepsy syndromes, reported a debilitating effect of sleep-related epileptic activity on memory functioning.

CONCLUSIONS

Conclusions from existing studies were hampered by small sample sizes, heterogeneous patient groups, and variations in memory assessment techniques. Overall, results to date preclude any definitive conclusions on the alteration of sleep-related memory consolidation in epilepsy. We discuss methodological considerations specific to people with epilepsy and provide suggestions on how to best investigate the relationship between epileptic activity, sleep, and memory consolidation in future studies.

CITATION

Latreille V, Schiller K, Peter-Derex L, Frauscher B. Does epilepticimpair sleep-related memory consolidation in epilepsy? A critical and systematic review. J Clin Sleep Med. 2022;18(10):2481-2495.

The interaction between circadian rhythm and epilepsy

Evidence about the interaction between circadian rhythms (CR) and epilepsy has been expanded with the application of advanced detection technology. An adequate understanding of how circadian system and epilepsy interact with each other could contribute to more accurate seizure prediction as well as rapid development of potential treatment timed to specific phases of CR. In this review, we present the reciprocal relationship between CR and epileptic activities from aspects of sleep effect, genetic modulation and brain biochemistry. It has been found that sleep-wake patterns, circadian timing systems and multidien rhythms have essential roles in seizure activities and interictal epileptiform discharge (IED). For instance, specific distribution patterns of seizures and IED have been reported, i.e., lighter non-rapid eye movement (NREM) sleep stage (stage 2) induces seizures while deeper NREM sleep stage (stage 3) activates IEDs. Furthermore, the epilepsy type, seizure type and seizure onset zone can significantly affect the rhythms of seizure occurrence. Apart from the common seizure types, several specific epilepsy syndromes also have a close correlation with sleep-wakefulness patterns. Sleep influences the epilepsy rhythm, and conversely, epilepsy alters the sleep rhythm through multiple pathways. Clock genes accompanied by two feedback loops of regulation have an important role in cortical excitability and seizure occurrence, which may be involved in the mTORopathy. The suprachiasmatic nuclei (SCN) has a rhythm of melatonin and cortisol secretion under the circadian pattern, and then these hormones can feed back into a central oscillator to affect the SCN-dependent rhythms, leading to variable but prominent influence on epilepsy. Furthermore, we discuss the precise predictive algorithms and chronotherapy strategies based on different temporal patterns of seizure occurrence for patients with epilepsy, which may offer a valuable indication for non-invasive closed-loop treatment system. Optimization of the time and dose of antiseizure medications, and resynchronization of disturbed CR (by hormone therapy, light exposure, ketogenic diet, novel small molecules) would be beneficial for epileptic patients in the future. Before formal clinical practice, future large-scale studies are urgently needed to assist prediction and treatment of circadian seizure activities and address unsolved restrictions.

Sleep and epilepsy: A snapshot of knowledge and future research lines

Sleep and epilepsy have a reciprocal relationship, and have been recognized as bedfellows since antiquity. However, research on this topic has made a big step forward only in recent years. In this narrative review we summarize the most stimulating discoveries and insights reached by the "European school." In particular, different aspects concerning the sleep-epilepsy interactions are analysed: (a) the effects of sleep on epilepsy; (b) the effects of epilepsy on sleep structure; (c) the relationship between epilepsy, sleep and epileptogenesis; (d) the impact of epileptic activity during sleep on cognition; (e) the relationship between epilepsy and the circadian rhythm; (f) the history and features of sleep hypermotor epilepsy and its differential diagnosis; (g) the relationship between epilepsy and sleep disorders.

Interictal Spikes as an EEG Biomarker of Cognitive Impairment

SUMMARY

Although interictal spikes (IISs) are a well-established EEG biomarker for epilepsy, whether they are also a biomarker of cognitive deficits is unclear. Interictal spikes are dynamic events consisting of a synchronous discharge of neurons producing high frequency oscillations and a succession of action potentials which disrupt the ongoing neural activity. There are robust data showing that IISs result in transitory cognitive impairment with the type of deficit specific to the cognitive task and anatomic location of the IIS. Interictal spike, particularly if frequent and widespread, can impair cognitive abilities, through interference with waking learning and memory and memory consolidation during sleep. Interictal spikes seem to be particularly concerning in the developing brain where animal data suggest that IISs can lead to adverse cognitive effects even after the disappearance of the spikes. Whether a similar phenomenon occurs in human beings is unclear. Thus, although IISs are a clear biomarker of transitory cognitive impairment, currently, they lack sensitivity and specificity as a biomarker for enduring cognitive impairment.

Cognitive impairment following experimental febrile seizures is determined by sex and seizure duration

BACKGROUND

Febrile seizures are the most common type of seizures in children. While in most children the outcome is favorable, children with febrile status epilepticus may exhibit modest cognitive impairment. Whether children with other forms of complex febrile seizure, such as repetitive febrile seizures within the same illness are at risk of cognitive deficits is not known. In this study, we used a well-established model of experimental febrile seizures in rat pups to compare the effects of febrile status epilepticus and recurrent febrile seizures on subsequent spatial cognition and anxiety.

METHODS

Male and female rat pups were subjected to hyperthermic seizures at postnatal day 10 and were divided into groups of rats with continuous seizures for ≥40 min or recurrent febrile seizures. They were then tested as adults in the active avoidance and spatial accuracy tests to assess spatial learning and memory and the elevated plus maze to measure anxiety.

RESULTS

Febrile status epilepticus rats demonstrated impaired spatial cognition in active avoidance and spatial accuracy and exhibited reduced anxiety-like behavior in the elevated plus maze. Rats with recurrent febrile seizures did not differ significantly from the controls on any measures. There were also significant sex-related differences with females with FSE performing far better than males with FSE in active avoidance but demonstrating a navigational learning impairment relative to CTL females in spatial accuracy. However, once learned, females with FSE performed the spatial accuracy task as well as CTL females.

CONCLUSION

There is a duration-dependent effect of febrile seizures on subsequent cognitive and behavioral outcomes. Febrile status epilepticus resulted in spatial cognitive deficits and reduced anxiety-related behaviors whereas rats with recurrent febrile seizures did not differ from controls. Sex had a remarkable effect on spatial cognitive outcome where males with FSE fared worse than females with FSE. The results demonstrate that sex should be considered as a biological variable in studies evaluating the effects of seizures on the developing brain.

Systematic review of executive functions in children with self-limited epilepsy with centrotemporal spikes

Self-limited Epilepsy with Centrotemporal Spikes (ECTS) is a self-limiting childhood epilepsy with an overall good prognosis. The neurocognitive profile of ECTS shows various degrees of neuropsychological impairment, with speech impairment and executive dysfunction being the most prominent. This review aimed to clarify the executive function (EF) profile of children with ECTS and the clinical variables' impact on these abilities. We conducted a systematic review of the relevant literature for articles published up to January 2021. Demographic and clinical characteristics were abstracted from the original records. EF tasks used in the studies were classified according to Diamond's model, which identified four components: working memory, inhibitory control, cognitive flexibility, and higher order EFs. Twenty-three studies were included. Among the included records, 14 studies examined working memory, 15 inhibitory control, 15 flexibility, 4 higher order EFs, and 2 general EFs. Results confirmed the presence of a specific impairment in two abilities: inhibitory control and cognitive flexibility. This review confirms the need to assess each EF both in verbal and visual-spatial tasks. The early detection of children with ECTS at risk of developing neuropsychological impairment could activate interventions and prevent worse school achievement, social functioning, and a poor quality of life. Systematic review registration: PROSPERO: CRD42021245959.

Memory Deficit in Patients With Temporal Lobe Epilepsy: Evidence From Eye Tracking Technology

Objective: To explore quantitative measurements of the visual attention and neuroelectrophysiological relevance of memory deficits in temporal lobe epilepsy (TLE) by eye tracking and electroencephalography (EEG).

Methods: Thirty-four TLE patients and twenty-eight healthy controls were invited to complete neurobehavioral assessments, cognitive oculomotor tasks, and 24-h video EEG (VEEG) recordings using an automated computer-based memory assessment platform with an eye tracker. Visit counts, visit time, and time of first fixation on areas of interest (AOIs) were recorded and analyzed in combination with interictal epileptic discharge (IED) characteristics from the bilateral temporal lobes.

Results: The TLE patients had significantly worse Wechsler Digit Span scores [F(1, 58) = 7.49, p = 0.008]. In the Short-Term Memory Game with eye tracking, TLE patients took a longer time to find the memorized items [F(1, 57) = 17.30, p < 0.001]. They had longer first fixation [F(1, 57) = 4.06, p = 0.049] and more visit counts [F(1, 57) = 7.58, p = 0.008] on the target during the recall. Furthermore, the performance of the patients in the Digit Span task was negatively correlated with the total number of IEDs [r(28) = −0.463, p = 0.013] and the number of spikes per sleep cycle [r(28) = −0.420, p = 0.026].

Conclusion: Eye tracking appears to be a quantitative, objective measure of memory evaluation, demonstrating memory retrieval deficits but preserved visual attention in TLE patients. Nocturnal temporal lobe IEDs are closely associated with memory performance, which might be the electrophysiological mechanism for memory impairment in TLE.

Clinical and electrophysiological predictors of behavioral disorders in patients with benign childhood epilepsy with centrotemporal spikes

PURPOSE

Long-term seizure and developmental outcomes of benign childhood epilepsy with centrotemporal spikes (BECTS) are thought to be good. Studies have shown that behavioral disorders may accompany BECTS. We aimed to investigate the frequency of behavioral disorders in patients with BECTS and evaluate their relationship to epilepsy features.

METHODS

Data for 41 patients with BECTS followed up at our clinic between December 2019 and June 2020 were analyzed. Behavioral disorders and intelligence were evaluated by the Turgay Diagnostic and Statistical Manual of Mental Disorders 4th Edition - Disruptive Behaviour Disorders Rating Scale and Wechsler Intelligence Scale for Children Revised, respectively. Patients with a diagnosis of BECTS were divided into 2 groups: children with a behavioral disorder and children without a behavioral disorder. Demographic characteristics, clinical and electroencephalography (EEG) findings, and intelligence level were compared between the two groups.

RESULTS

Twelve of the patients (29%) were classified as having attention-deficit/hyperactivity disorder (ADHD) and 2 (5%) were classified as having oppositional defiant disorder (ODD). The age at seizure onset was earlier in patients with behavioral disorders (p = 0.023). Bilateral interictal epileptic discharges (IEDs) were more common in children with behavioral disorders than children without behavioral disorders (p = 0.039). The most preferred antiseizure medication was carbamazepine, followed by levetiracetam and valproic acid. The intelligence score of the patients with BECTS was in the normal range in both groups. The total, verbal, and performance scores were lower in patients with a behavioral disorder than in patients without a behavioral disorder, but there was no statistically significant difference between the two groups.

CONCLUSION

Behavioral disorders may be present in approximately one-third of patients with BECTS. Early onset of seizures and the presence of bilateral IEDs may be risk factors for behavioral disorders in children with BECTS.

Executive functioning in children with self-limited epilepsy with centrotemporal spikes: a systematic review and meta-analysis

Self-limited epilepsy with centrotemporal spikes (ECTS) is one of the most frequent focal epilepsies amongst children. Because remission usually occurs before 16 years old and patients present infrequent clinical manifestation, ECTS was considered benign for a long time. Despite the reports on cognitive deficits associated with ECTS in the last years, knowledge about the condition's specific executive function domains (inhibitory control, working memory, cognitive flexibility, verbal fluency, and higher-order executive functions) is still lacking. The following systematic review was conducted according to PRISMA guidelines. The PubMed and Scopus databases and gray literature were searched according to the following eligibility criteria: (1) original articles published in peer-review journals; (2) studies that present assessment of children with ECTS; and (3) studies with an available assessment of the executive function of the participants. A total of 43 studies (1179 patients and 1086 healthy controls) met the inclusion criteria. Data from 19 studies were extracted, and meta-analysis methods were used to compare results in the three main executive function domains and verbal fluency. The study quality was measured through the Newcastle-Ottawa Scale (NOS) and the evidence quality with the GRADEpro tool. Results and conclusions: The present systematic review is the first to gather information about executive functioning in children with ECTS. According to the meta-analyses, children with ECTS show weaker performances when compared with a control group in inhibitory control, cognitive flexibility, and verbal fluency. However, because the quality of evidence was classified as very low, caution is needed when interpreting the strength of the results.

Delayed brain development of Rolandic epilepsy profiled by deep learning-based neuroanatomic imaging

OBJECTIVES

Although Rolandic epilepsy (RE) has been regarded as a brain developmental disorder, neuroimaging studies have not yet ascertained whether RE has brain developmental delay. This study employed deep learning-based neuroanatomic biomarker to measure the changed feature of "brain age" in RE.

METHODS

The study constructed a 3D-CNN brain age prediction model through 1155 cases of typically developing children's morphometric brain MRI from open-source datasets and further applied to a local dataset of 167 RE patients and 107 typically developing children. The brain-predicted age difference was measured to quantitatively estimate brain age changes in RE and further investigated the relevancies with cognitive and clinical variables.

RESULTS

The brain age estimation network model presented a good performance for brain age prediction in typically developing children. The children with RE showed a 0.45-year delay of brain age by contrast with typically developing children. Delayed brain age was associated with neuroanatomic changes in the Rolandic regions and also associated with cognitive dysfunction of attention.

CONCLUSION

This study provided neuroimaging evidence to support the notion that RE has delayed brain development.

KEY POINTS

• The children with Rolandic epilepsy showed imaging phenotypes of delayed brain development with increased GM volume and decreased WM volume in the Rolandic regions. • The children with Rolandic epilepsy had a 0.45-year delay of brain-predicted age by comparing with typically developing children, using 3D-CNN-based brain age prediction model. • The delayed brain age was associated with morphometric changes in the Rolandic regions and attentional deficit in Rolandic epilepsy.

Sleep-dependent memory consolidation in children with self-limited focal epilepsies

OBJECTIVE

Children with self-limited focal epilepsies of childhood (SLFE) are known to show impaired memory functions, particularly in the verbal domain. Interictal epileptiform discharges (IED) in these epilepsies are more pronounced in nonrapid eye movement (NREM) sleep. Nonrapid eye movement sleep is crucial for consolidation of newly-encoded memories. Therefore, we hypothesize that sleep-dependent memory consolidation is altered in relation to IED in children with SLFE.

METHODS

We conducted a prospective case-control study. We applied a verbal (word pair) and a visuospatial (two-dimensional [2D] object location) learning task, both previously shown to benefit from sleep in terms of memory consolidation. Learning took place in the evening, and retrieval was tested in the morning after a night of sleep. Electroencephalogram (EEG) was recorded across night. After sleep-stage scoring, the spike-wave index (SWI) was assessed at the beginning and the end of sleep. Fourteen patients with SLFE (age: 5.5 to 11.6 years) were compared with 15 healthy controls (age: 6.8 to 9.1 years) examined in a previous study.

RESULTS

In contrast to healthy controls (mean: +12.9% recalled word pairs, p = .003, standard deviation (SD) = 12.4%), patients did not show overnight performance gains in the verbal memory task (mean: +6.4% recalled word pairs, p > .05, SD = 17.3) Neither patients nor controls showed significant overnight changes in visuospatial task performance. Spike-wave index was negatively correlated with recall performance in the verbal but not in the visuospatial task.

SIGNIFICANCE

We found evidence for impaired overnight improvement of performance in children with SLFE in a verbal learning task, with high SWI rates predicting low recall performance. We speculate that spike-waves hamper long-term memory consolidation by interfering with NREM sleep.

ADHD and ADHD-related neural networks in benign epilepsy with centrotemporal spikes: A systematic review

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) and benign epilepsy with centrotemporal spikes (BECTS or rolandic epilepsy) present with a very high level of comorbidity. We aimed to review the existing literature focusing on two aspects: the possible role of epileptic activity in the damage of ADHD-related neural networks and the clinical approach to patients presenting with both conditions.

MATERIAL AND METHODS

A systematic review was performed using Sapienza Library System and PubMed. The following search terms have been considered: attention networks, ADHD, attention systems, rolandic epilepsy, benign epilepsy with centrotemporal spikes, centrotemporal spikes epilepsy, and focal epilepsy in children. The target population consisted of patients under 18 years of age diagnosed with either BECTS and ADHD or healthy controls.

RESULTS

Nine case-control and cohort studies have been selected. The reported prevalence of ADHD in patients with BECTS was around 60%. No clinical correlation was found between the medical records and the presence of ADHD in patients with BECTS, if not due to febrile convulsion (FC). One study showed higher levels of bilateral discharges in patients with severe ADHD. The negative influence of the age at onset of seizures was demonstrated on attention but not on intelligence quotient (IQ). Moreover, the frequency of seizures and the occurrence of discharges during nonrapid eye movement (NREM) sleep were correlated to attention impairment. From a neurobiological point of view, functional connectivity in patients with BECTS and ADHD appears to be disrupted. Two studies reported a specific impairment in selective visual attention, while one study underlined a decreased activation of the dorsal attention network (DAN). Two different studies found that patients with BECTS and comorbid ADHD presented with altered thickness in their magnetic resonance imaging (MRI) scans in the cortical and subcortical regions (including the frontal lobes, lingual-fusiform cortex, cuneus and precuneus, limbic area and pericalcarine cortex among others). This might explain the cognitive and behavioral symptoms such as poor selective visual attention, speech disturbance, and impulsivity.

CONCLUSIONS

Despite BECTS being considered to have a relative benign course, many studies have documented cognitive and/or behavioral problems in patients diagnosed with this type of epilepsy. In particular, children affected by rolandic epilepsy should receive a complete neuropsychological evaluation at seizure onset considering the high rate of comorbidity with ADHD. A further investigation of the common pathogenic substrate is desirable to better orientate the clinical and therapeutic interventions applied.

Oral language in children with benign childhood epilepsy with centrotemporal spikes

PURPOSE

Benign childhood epilepsy with centrotemporal spikes is one of the most common childhood disorders. Despite the benignity usually attributed to this epileptic syndrome, several studies have demonstrated that these children have cognitive disabilities. Among these disturbances, language disorders have been the less studied in depth. We aimed to obtain accurate information about the language skills of children with this epileptic syndrome and to explore the correlation between demographic and clinical factors associated with epilepsy and the language skills.

METHODS

We assessed 30 children with this epileptic syndrome, followed in three hospitals in Lisbon, and 60 controls, aged between 6 and 12 years, attending the same schools and matched by age, gender, and parents' socioprofessional level. All the included children did not present cognitive impairment (reasoning ability, verbal memory), sensory, or motor limitations. The evaluation tests covered all language areas.

RESULTS

Overall, children with this epileptic syndrome had lower skills in the majority of the language areas, when compared with their peers. These children showed greater difficulties in semantics and syntax domains. The atypical evolution of the seizures and a longer duration of epilepsy were the clinical variables that most influence the language skills of our samples.

CONCLUSION

The early assessment of these capacities and the possible need for therapeutic intervention should be emphasized, in order to minimize the impact on their academic performance and quality of life.

Social cognition in childhood epilepsy with centrotemporal spikes

PURPOSE

Social cognition is involved in the perception, processing, and interpretation of social information. For this reason, social cognition is a crucial domain for successful communication and interpersonal relationships. With this in mind, we aimed to assess social cognition in children with Self-Limited Childhood Epilepsy with Centrotemporal Spikes (CECTS) and its association with traditional executive function tests and clinical variables of epilepsy.

METHODS

We evaluated 23 patients with CECTS (65% male, mean age of 10.64 years) and 20 healthy children (75% male, mean age of 10.15 years). We used the Faux-Pas Child Task (FP) to analyze social cognition and a comprehensive battery of neuropsychological tests to evaluate domains of classic executive functions.

RESULTS

Patients with CECTS had impairments in FP compared to healthy children [p < 0.001]. Impairments in some areas of traditional executive functions were related to worse social cognition in patients with CECTS. Epilepsy-related factors did not impair the performance on FP, except for the number of antiseizure medication [p = 0.016].

CONCLUSIONS

Social cognition is impaired in children and adolescents with CECTS. The presence of ongoing seizures and frequent epileptiform activity were not correlated with social cognition. Therefore, epilepsy per se was more relevant for social cognition than its severity.

Oromotor, word retrieval, and dichotic listening performance in young adults with previous Rolandic epilepsy

AIMS

Results from a previous study indicated that children with Rolandic epilepsy (RE) exhibit abnormalities of oromotor and dichotic listening performance. The current study aimed to investigate whether the same individuals, 10 years later, still exhibited differences between the groups. Earlier literature suggests that children with RE normalize after remission and as they become adults. More recent studies have, on the contrary, suggested that there is a risk for residual oromotor and language deficits after remission.

METHODS

Eleven young adults with RE and 9 matched controls were retested 10 years after participating in a study investigating oromotor ability, articulation, dichotic listening ability, and phonological and semantic word retrieval.

RESULTS

Results of this longitudinal study indicated that there was a persistent, albeit reduced, difference between the groups, after remission, in dichotic listening and, to some extent, oromotor performance. Articulation and word retrieval did not differ between the groups.

CONCLUSION

Young adults with previous RE in childhood have a moderate risk for persistent difficulties in verbal perception and oromotor performance.

Epilepsy syndromes of childhood with sleep activation: Insights from functional imaging

In epilepsy syndromes of childhood with sleep activation, defined as the spectrum of epileptic conditions going from classical benign childhood epilepsy with centrotemporal spikes (BECTS) to epileptic encephalopathy (EE) with continuous spike and waves during slow-wave sleep (CSWS) including Landau-Kleffner syndrome (LKS), a lot of functional imaging studies have been performed so far, leading to results that are not always consistent, related to the technique of neuroimaging performed and to the variability of the clinical phenotype. Most consistent findings are, depending of the method used, activations or increased regional glucose metabolism in the epileptogenic regions, and deactivations, hypometabolism or decreased functional connectivity in cortical regions that belong to the default mode network. Functional changes are either transitory, temporally related to the occurrence of interictal epileptiform discharges (IED), or permanent, persisting across IED-free periods. Some studies have shown that the more severe phenotype, i.e. EE with CSWS, displays the more profound functional disturbances. Taken together, functional imaging studies support the concept that IED impact cognition in epilepsy syndromes of childhood with sleep activation. However, the precise chronology between the occurrence of IED and the functional disturbances, the neuropsychological correlates of the functional disturbances, and the effects of the anti-epileptic treatments on IED, functional disturbances and cognition need to be further studied.

Attention profile in children with epilepsy compared to healthy children using computer-based ForamenRehab program

Attention is a key component in cognitive functioning. Attention impairment is often present in children with epilepsy, which is one of the most common neurological disorders in children and adolescents. Evaluating the attention profiles is important for describing the patients' cognitive weaknesses and planning individual-based cognitive neurorehabilitation. The aim of this study was to assess the attention profiles of children with epilepsy and compare the results to neurologically healthy children. Twenty-nine children with epilepsy aged 8-12 years and 19 neurologically healthy age-matched comparison group participated in assessments with baseline tasks of the Attention module of ForamenRehab computer-program. Four separate attention components were measured - focused, sustained, complex, and tracking - to reveal the most impaired aspects of attention. At the baseline level, patients showed impairments in different attention function components compared to comparison group. Children with epilepsy had significantly lower results in sustained, complex attention, and tracking components (p < 0.05). The patients had similar results with comparison group only in one component - focused attention. All children had quicker visual reaction times compared to their auditory reaction times. The results emphasize the need for attention rehabilitation in children with epilepsy and help to focus on specific components of attention in planning the intervention process.

Functional and Structural Network Disorganizations in Typical Epilepsy With Centro-Temporal Spikes and Impact on Cognitive Neurodevelopment

Epilepsy with Centrotemporal Spikes (ECTS) is the most common form of self-limited focal epilepsy. The pathophysiological mechanisms by which ECTS induces neuropsychological impairment in 15-30% of affected children remain unclear. The objective of this study is to review the current state of knowledge concerning the brain structural and functional changes that may be involved in cognitive dysfunctions in ECTS. Structural brain imaging suggests the presence of subtle neurodevelopmental changes over the epileptogenic zone and over distant regions in ECTS. This structural remodeling likely occurs prior to the diagnosis and evolves over time, especially in patients with cognitive impairment, suggesting that the epileptogenic processes might interfere with the dynamics of the brain development and/or the normal maturation processes. Functional brain imaging demonstrates profound disorganization accentuated by interictal epileptic spikes (IES) in the epileptogenic zone and in remote networks in ECTS. Over the epileptogenic zone, the literature demonstrates changes in term of neuronal activity and synchronization, which are effective several hundred milliseconds before the IES. In the same time window, functional changes are also observed in bilateral distant networks, notably in the frontal and temporal lobes. Effective connectivity demonstrates that the epileptogenic zone constitutes the key area at the origin of IES propagation toward distant cortical regions, including frontal areas. Altogether, structural and functional network disorganizations, in terms of: (i) power spectral values, (ii) functional and effective connectivity, are likely to participate in the cognitive impairment commonly reported in children with ECTS. These results suggest a central and causal role of network disorganizations related to IES in the neuropsychological impairment described in ECTS children.

EEG Abnormalities as a Neurophysiological Biomarker of Severity in Autism Spectrum Disorder: A Pilot Cohort Study

To date, the phenotypic significance of EEG abnormalities in patients with ASD is unclear. In a population affected by ASD we aimed to evaluate: the phenotypic characteristics; the prevalence of EEG abnormalities; the potential correlations between EEG abnormalities and behavioral and cognitive variables. Sixty-nine patients with ASD underwent cognitive or developmental testing, language assessment, and adaptive behavior skills evaluation as well as sleep/wake EEG recording. EEG abnormalities were found in 39.13% of patients. EEG abnormalities correlated with autism severity, hyperactivity, anger outbursts, aggression, negative or destructive behavior, motor stereotypies, intellectual disability, language impairment and self-harm. Our findings confirmed that EEG abnormalities are present in the ASD population and correlate with several associated phenotypic features.

Construction and disruption of spatial memory networks during development

Spatial memory, the aspect of memory involving encoding and retrieval of information regarding one's environment and spatial orientation, is a complex biological function incorporating multiple neuronal networks. Hippocampus-dependent spatial memory is not innate and emerges during development in both humans and rodents. In children, nonhippocampal dependent egocentric (self-to-object) memory develops before hippocampal-dependent allocentric (object-to-object) memory. The onset of allocentric spatial memory abilities in children around 22 mo of age occurs at an age-equivalent time in rodents when spatially tuned grid and place cells arise from patterned activity propagating through the entorhinal-hippocampal circuit. Neuronal activity, often driven by specific sensory signals, is critical for the normal maturation of brain circuits This patterned activity fine-tunes synaptic connectivity of the network and drives the emergence of specific firing necessary for spatial memory. Whereas normal activity patterns are required for circuit maturation, aberrant neuronal activity during development can have major adverse consequences, disrupting the development of spatial memory. Seizures during infancy, involving massive bursts of synchronized network activity, result in impaired spatial memory when animals are tested as adolescents or adults. This impaired spatial memory is accompanied by alterations in spatial and temporal coding of place cells. The molecular mechanisms by which early-life seizures lead to disruptions at the cellular and network levels are now becoming better understood, and provide a target for intervention, potentially leading to improved cognitive outcome in individuals experiencing early-life seizures.

Changes in functional organization and functional connectivity during story listening in children with benign childhood epilepsy with centro-temporal spikes

Children with Benign Epilepsy with Centrotemporal Spikes (BECTS), despite high likelihood for seizure remission, are reported to have subtle difficulties in language and other cognitive skills. We used functional MRI and a story listening task to examine the effect of BECTS on patterns of activation and connectivity. Language and cognitive skills were assessed using standardized measures. Twenty-four children with recently diagnosed BECTS and 40 typically-developing children participated. In a functionally-defined region of interest in right inferior frontal gyrus, BECTS patients showed a lower level of activation. Across both groups combined, increased activation in superior/middle temporal regions of interest was associated with better language scores. Connectivity in the story processing network was similar between groups, but connectivity within left inferior frontal gyrus was decreased in children with BECTS. These results suggest that language networks are largely maintained in new-onset BECTS, but some subtle changes in activation and connectivity can be observed.

Delayed cortical maturation at the centrotemporal brain regions in patients with benign childhood epilepsy with centrotemporal spikes (BCECTS)

Benign childhood epilepsy with centrotemporal spikes (BCECTS) is an epilepsy syndrome commonly found in child and adolescent. Although the prognosis is mostly favorable as long as the seizure is well controlled. However, they are often suffering from the cognitive and behavioral problems which might be the consequences of the initial insults. It is still not clear whether the initial epileptiform discharges has long term impact on the resting-state brain activities at later ages. This study investigated the resting-state brain activities in BCECTS patients with clinical seizure remission stage (n = 16; 11 males) and compared with the non-epileptic, age-matched control subjects. Quantitative electroencephalography (qEEG) revealed a significantly higher absolute power of the theta and alpha waves in BCECTS patients with clinical seizure remission as compared with the non-epileptic control subjects. Interestingly, the differences were observed mainly over the centrotemporal electrodes which are the common sites of the initial epileptiform discharges. The differences were more significant in patients with bilateral epileptiform discharges than those with the unilateral epileptic activities. Typically, the brain wave power continuously decreases with increasing ages. Therefore, higher absolute powers of the brain waves indicate more delayed in cortical maturation compared with the non-epileptic control group. These findings indicated that BCECTS patients have delay cortical maturation at the centrotemporal brain regions even at the clinical seizure remission phase.

The neuropsychological profile of parietal and occipital lobe epilepsy

Despite the extensive body of research in clinical neurology on the functional organization of posterior cortices, parietal and occipital lobe epilepsy (PLE and OLE) have not as yet received the attention afforded frontal and temporal lobe epilepsy (FLE and TLE), perhaps due to their low prevalence. Posterior epilepsies however, represent a challenge for epileptology in general and neuropsychological differential diagnosis in particular. Our main purpose was to examine the likely existence of a pattern of cognitive dysfunction characterizing patients suffering from seizures with a parietal and/or occipital ictal onset. We hypothesized that such patients would present difficulties in the visuospatial and visuoconstructive domains, since spatial analysis and synthesis is an inherent feature of posterior cortical systems. Participants were 14 patients with epilepsy and 14 healthy controls matched for demographic characteristics (gender, age, and education level). We used an extensive battery of neuropsychological tests to assess auditory-verbal memory and learning, episodic memory, attention and working memory, verbal abilities, haptic perception, arithmetic abilities, and executive functions. Special attention was given to visuospatial abilities. Depression and anxiety symptoms were assessed through a self-administered questionnaire. Nonparametric (Mann-Whitney U test) statistical tests were conducted. We found that patients with epilepsy performed significantly worse in visuoconstruction, verbal, and executive functions compared to their healthy matches. Finally, we interpret our findings from the perspective of Luria of mental functions organized into functional systems and the current trends in epileptology to view epilepsy as a system (network) problem.

Levetiracetam versus carbamazepine in treatment of rolandic epilepsy

PURPOSE

The aim of the current study was to systematically review the literature to compare the efficacy of levetiracetam (LEV) with that of carbamazepine (CBZ) to control seizures and reduce the burden of interictal epileptiform discharges in children with rolandic epilepsy (RE) and also to compare their tolerability.

METHODS

We searched the electronic database PubMed on January 9, 2019 for original articles that included the following English-language search terms in the title: "Rolandic epilepsy" OR "benign childhood epilepsy with centrotemporal spikes" since 2000. We concentrated our review on three main areas: 1. Neuropsychological impairments in children with RE; 2. Influence of epileptic activity on cognitive performance in RE; 3. Effects of antiepileptic drug (AED) therapies in RE.

RESULTS

The primary search yielded 308 papers. We reviewed the results and removed duplicate articles and all nonoriginal, non-English papers. Finally, after carefully reviewing the full texts, we included 44 original articles to achieve the aims of this review.

CONCLUSION

Physicians taking care of children with RE should be aware of the risks for cognitive dysfunctions in these patients and screen their patients for any subtle dysfunction that may affect their academic performance and achievement. If and when the physician decides to prescribe an AED for their patients with RE, LEV is probably a better option compared with CBZ to prescribe for these children.

Effect of sleep quality on memory, executive function, and language performance in patients with refractory focal epilepsy and controlled epilepsy versus healthy controls - A prospective study

We aimed to evaluate the effect of sleep quality on memory, executive function, and language performance in patients with refractory focal epilepsy and controlled epilepsy and compare these with healthy individuals. We prospectively enrolled 37 adolescent and adult patients with refractory focal epilepsy (Group 1) and controlled epilepsy (Group 2) in each group. History pertaining to epilepsy and sleep were recorded, and all patients underwent overnight polysomnography. Language, memory, and executive function assessments were done using Western Aphasia Battery, Post Graduate Institute (PGI) memory scale, and battery of four executive function tests (Trail Making Test A & B, Digit symbol test, Stroop Task, and Verbal Fluency Test), respectively. Forty age- and sex-matched controls were also included in the study. Significant differences were noted in both objective and subjective sleep parameters among all the groups. On polysomnography, parameters like total sleep time, sleep efficiency, sleep latency, and rapid eye movement (REM) latency were found to be significantly worse in Group 1 as compared with Group 2. Cognitive and executive parameters were significantly impaired in Group 1. Shorter total sleep time, poorer sleep efficiency, and prolonged sleep latencies were observed to be associated with poor memory and executive function in patients with refractory epilepsy. Our study strongly suggests that sleep disturbances, mainly shorter total sleep time, poor sleep efficiency, and prolonged sleep latencies, are associated with impaired memory and executive function in patients with refractory focal epilepsy and to a lesser extent, among those with medically controlled epilepsy.

The association of epileptic focus estimated by magnetoencephalography with cognitive function in non-lesional epilepsy with continuous spikes and waves during slow wave sleep (ECSWS) children

OBJECTIVE

Epilepsy with continuous spikes and waves during slow sleep (ECSWS) is associated with cognitive deficits. The underlying mechanism is thought to relate to disturbance of functions of the foci by the persistent epileptic activity. However, the relationship between epileptic foci and cognitive deficits remains largely unknown, except for in Landau-Kleffner syndrome. The aim of this study was to evaluate the relationship of epileptic foci estimated from magnetoencephalography (MEG) with cognitive functions at the period of diagnosis in non-lesional ECSWS children, excluding those with Landau-Kleffner syndrome.

METHODS

MEG data and the Wechsler intelligence scale for children-III scores at ECSWS diagnosis, and medical records, were reviewed. Multiple regression analysis was performed to examine the relationship of parameters of MEG spike dipole clusters, including anatomical location or laterality, with the Wechsler intelligence scale for children-III scores at ECSWS diagnosis.

RESULTS

Sixteen patients were included, all of whom were right-handed. Epilepsy onset (first unprovoked seizure) ranged from 31 to 110 months (mean, 68.5). The age at ECSWS diagnosis ranged from 72 to 156 months (mean, 108.9). The dipole clusters were estimated on the right Rolandic area (RA) in 4 patients (25%), right supramarginal gyrus (SMG) in 3 (19%), left RA in 2 (13%), left SMG in 2 (13%), bilateral RA in 3 (19%), multiple anatomical locations in 2 (13%). The age at epilepsy onset had the strongest prognostic effect, and full-scale intelligence quotient was relatively less-affected if the cluster was found on the SMG (β = 14.7, p = 0.031). Cases with only a right side cluster exhibited reduced impairment of perceptual organization compared with those with only a left side cluster or bilateral clusters (β = 17.48, p = 0.02). In 12 patients, long-term intellectual prognosis was evaluated, and was associated with intellectual level at the period of ECSWS diagnosis.

CONCLUSION

In non-lesional ECSWS, the relationship between epileptic focus and cognitive deficits differs from that observed in adults. Rather, it is similar to epilepsies associated with congenital or early infantile brain insults, in that the left epileptic foci in right-handed patients were associated with lower non-verbal functions. Future studies are required to determine the role of plasticity of the immature brain in driving these differences.

Strong relationship between NREM sleep, epilepsy and plastic functions - A conceptual review on the neurophysiology background

The aim of this review is to summarize and discuss the strong bond between NREM sleep and epilepsy underlain by the shared link and effect on brain plasticity. Beyond the seizure occurrence rate, sleep relatedness may manifest in the enhancement of interictal epileptic discharges (spikes and pathological ripples). The number of the discharges as well as their propagation increase during NREM sleep, unmasking the epileptic network that is hidden during wakefulness. The interictal epileptic discharges associate with different sleep constituents (sleep slow waves, spindling and high frequency oscillations); known to play essential role in memory and learning. We highlight three major groups of epilepsies, in which sleep-related plastic functions suffer an epileptic derailment. In absence epilepsy mainly involving the thalamo-cortical system, sleep spindles transform to generalized spike-wave activity. In mesio-temporal epilepsy affecting the hippocampal declarative memory system, the sharp wave ripples derail to dysfunctional epileptic oscillations (spikes and pathological ripples). Idiopathic childhood epilepsies affecting the perisylvian network may progress to catastrophic status electricus during NREM sleep. In these major epilepsies, NREM sleep has a pivotal role in the development and course of the disorder. Epilepsy is born in-, and exhibits its pathological properties during NREM sleep. Interictal discharges are important causative agents in this process.

Interictal spike connectivity in human epileptic neocortex

OBJECTIVE

Interictal spikes are a biomarker of epilepsy, yet their precise roles are poorly understood. Using long-term neocortical recordings from epileptic patients, we investigated the spatial-temporal propagation patterns of interictal spiking.

METHODS

Interictal spikes were detected in 10 epileptic patients. Short time direct directed transfer function was used to map the spatial-temporal patterns of interictal spike onset and propagation across different cortical topographies.

RESULTS

Each patient had unique interictal spike propagation pattern that was highly consistent across times, regardless of the frequency band. High spiking brain regions were often not spike onset regions. We observed frequent spike propagations to shorter distances and that the central sulcus forms a strong barrier to spike propagation. Spike onset and seizure onset seemed to be distinct networks in most cases.

CONCLUSIONS

Patients in epilepsy have distinct and unique network of causal propagation pattern which are very consistent revealing the underlying epileptic network. Although spike are epileptic biomarkers, spike origin and seizure onset seems to be distinct in most cases.

SIGNIFICANCE

Understanding patterns of interictal spike propagation could lead to the identification patient-specific epileptic networks amenable to surgical or other treatments.

The Impact of Interictal Discharges on Performance

PURPOSE OF REVIEW

Our purpose is to review evidence relating to the concept that interictal epileptiform discharges (IEDs) impair brain performance.

RECENT FINDINGS

Sophisticated measures of motor and cognitive performance have clarified older observations, confirming that in both animals and humans, IEDs affect aspects of performance, IED morphology, frequency, anatomical distribution, and duration matter. However, we now know that it is difficult to draw a line between IEDs and seizures, not only by electrical criteria but even by metabolic and molecular measures. IEDs impair performance acutely and probably chronically. Thus, there are good theoretical reasons for suppressing them, but no consensus has been reached on how much effort this deserves. Many antiepileptic medications effective for control of clinical seizures have little effect on IEDs. Better methods of measuring outcomes may allow selection of individual patients for whom treatment aimed at IEDs is worthwhile.

Language skills in children with benign childhood epilepsy with centrotemporal spikes: A systematic review

Benign childhood epilepsy with centrotemporal spikes (BECTS) is the epileptic syndrome that most affects preschool and school-age children. Despite being usually considered a benign condition, several studies have shown that this epileptic syndrome is responsible for cognitive morbidities in children, namely at the level of attention and memory, as well as language. However, language disorders are still superficially addressed by the literature. This review aimed to compile and synthesize recent literature in this area. This systematic bibliographic research comprises studies published between 2005 and 2016 in PubMed, Science Direct, and PsycInfo computer databases that included the keywords "language", "cognition", "benign childhood epilepsy with centrotemporal spikes", "rolandic epilepsy", and "children". Studies were selected according to the following criteria: (i) published in scientific peer reviewed journals; (ii) performed with children between the ages of 3 and 16 years; and (iii) performed in children with BECTS in the active phase or after remission. Eighteen studies met these criteria. Nine studies mentioned language skill disorders in children with BECTS in the receptive and productive domains of semantics and seven studies in morphosyntax. Regarding phonological awareness, six studies have found limitations in the intrasyllabic, syllabic, and phonemic levels. These studies have also detected deficits in verbal fluency (semantic and phonemic) and in verbal memory. Because of the heterogeneity of the study samples and the use of innumerable distinct tasks in the evaluation of language skills, the results obtained still show some lack of consensus regarding the affected areas. Despite this, it was possible to synthesize and define more precisely the oral language variations presented by this population. We have concluded that the changes in semantic skills are the most frequently mentioned. The studies have also showed morphosyntactic and phonological disorders, in spite of showing some variability among them.

The relevance of attention deficit hyperactivity disorder in self-limited childhood epilepsy with centrotemporal spikes

In this study, we aimed to evaluate the attentional and executive functions in patients with benign childhood epilepsy with centrotemporal spikes (BCECTS) with and without attention-deficit hyperactivity disorder (ADHD) compared with controls and compared with patients with ADHD without epilepsy. We evaluated 12 patients with BCECTS and ADHD (66.7% boys; mean age of 9.67years); 11 children with non-ADHD BCECTS (63.6% boys; mean age of 11.91years); 20 healthy children (75% boys; mean age of 10.15years); and 20 subjects with ADHD without epilepsy (60% boys; mean age of 10.9years). We used a comprehensive battery of neuropsychological tests to evaluate attentional and executive functions in their broad domains. Patients with BCECTS and ADHD had worse performance in Conners' Continuous Performance Test II (reaction time standard error [p=0.008], variability [p=0.033], perseverations [p=0.044] and in reaction time interstimuli interval [p=0.016]). Patients with ADHD showed worse performance in Trail Making Test B errors [p=0.012]. In conclusion, patients with BCECTS and ADHD had worse executive and attentional performance compared with controls than non-ADHD patients with BCECTS. Regardless of the presence of epilepsy, ADHD also negatively impacted executive and attentional functions but in different executive subdomains compared with patients with epilepsy.

Brain responses to auditory oddball task in children with benign childhood epilepsy with centrotemporal spikes: Quantitative analysis and correlation with neuropsychological assessment scores

OBJECTIVE

Variable degrees of cognitive dysfunction have been reported in children with benign childhood epilepsy with centrotemporal spikes (BCECTS). Our aim was to perform quantitative analyses of the brain responses to cognitive tasks using event-related desynchronization (ERD) and event-related synchronization (ERS) and correlating the results with the scores of neuropsychological tests in patients with BCECTS.

METHODS

This case control study included 30 patients with BCECTS and 20 controls. Clinical assessment, neuropsychological tests, the Positive wave at 300 msec (P300) parameters recording, and quantitative electroencephalography (EEG) analysis were carried out for both groups. Alpha power ERD and ERS were measured in six different brain regions during an auditory oddball paradigm.

RESULTS

Children with epilepsy showed a statistically significant poorer performance in verbal intelligence quotient (IQ), performance IQ, and total scale IQ and lower number of correct responses. Moreover, both groups showed diffuse alpha power attenuation in response to the target tones. After summation of the alpha power ERD over all brain regions to get the net diffuse ERD, the patients' group showed a statistically significant smaller net alpha ERD compared with that of the control group (P=0.001). No significant correlations between the alpha ERD percentage, recorded P300 parameters, and neuropsychological tests scores were found.

CONCLUSIONS

Children with BCECTS have subtle cognitive dysfunction proved by significantly lower scores of verbal IQ and performance IQ subtests. The significantly smaller net diffuse alpha power ERD detected in children with epilepsy may be an electrophysiological indicator of disruptive brain activation in relation to cognitive attentional tasks; however, its correlation with neuropsychological tests was insignificant.

Polysomnographic Aspects of Sleep Architecture on Self-limited Epilepsy with Centrotemporal Spikes: A Systematic Review and Meta-analysis

Self-limited epilepsy with centrotemporal spikes is the most common paediatric epileptic syndrome, with growing evidence linking it to various degrees and presentations of neuropsychological dysfunction. The objective of this study is to evaluate the possible sleep macro and microstructural alterations in children with this diagnosis. A systematic review of published manuscripts was carried out in Medline, LILACS and Scielo databases, using the MeSH terms epilepsy, sleep and polysomnography. From 753 retrieved references, 5 were selected, and data from macro and, when available, microstructure of sleep were extracted. Meta-analysis was performed with data from 4 studies using standardized mean difference. Findings were heterogeneous between studies, being the most frequent macrostructural findings a smaller proportion and greater latency of REM sleep in two studies and, in meta-analysis, a longer sleep latency was the most significant finding among epileptic patients. Only one study evaluated sleep microstructure, suggesting possible alterations in cyclic alternating pattern in diagnosed children. Studies evaluating macro and microstructure of sleep in children with self-limited epilepsy with centrotemporal spikes are necessary to a better understanding of mechanisms of the neuropsychologic disturbances that are frequently seen in children with this diagnosis.

The influence of EEG-detected nocturnal centrotemporal discharges on the expression of core symptoms of ADHD in children with benign childhood epilepsy with centrotemporal spikes (BCECTS): A prospective study in a tertiary referral center

Benign childhood epilepsy with centrotemporal spikes (BCECTS) is the most frequent benign focal epilepsy in childhood. Although it is described as a benign epilepsy syndrome, many studies have revealed that a significant number of patients have some degree of neuropsychological impairment. Thirty-two patients with BCECTS aged 6-11years were included in the study. All patients (without any antiepileptic or psychiatric medication) underwent all-night EEG monitoring and complex neuropsychological testing to diagnose the presence of core symptoms of attention-deficit/hyperactivity disorder (ADHD). The spike index (number of spikes per minute) on awake and asleep EEG, age at seizure onset, family history of epilepsy, and perinatal risks were correlated with the results of neuropsychological testing. Of the 32 patients, 21 patients (65.6%) fulfilled the criteria for ADHD diagnosis. Children who were younger at epilepsy onset demonstrated lower IQ and higher attention deficit (P=0.004) and higher impulsivity (P=0.016). The occurence of epileptiform discharges on nocturnal EEG was positively related to higher attention deficit and higher impulsivity. The findings are discussed in terms of how interictal discharges in the centrotemporal region during sleep affect the development of cognitive functions in children during critical epochs of neuropsychological development.

Cognitive and behavioral comorbidities in Rolandic epilepsy and their relation with default mode network's functional connectivity and organization

OBJECTIVE

Rolandic epilepsy (RE) is characterized by typical interictal-electroencephalogram (EEG) patterns mainly localized in centrotemporal and parietooccipital areas. An aberrant intrinsic organization of the default mode network (DMN) due to repeated disturbances from spike-generating areas may be able to account for specific cognitive deficits and behavioral problems in RE. The aim of the present study was to investigate cognitive development (CD) and socioemotional development (SED) in patients with RE during active disease in relation to DMN connectivity and network topology.

METHODS

In 10 children with RE and active EEG, CD was assessed using the Wechsler Intelligence Scale for Children-IV (WISC-IV); SED was assessed using the Fünf-Faktoren-Fragebogen für Kinder (FFFK), a Big-Five inventory for the assessment of personality traits in children. Functional connectivity (FC) in the DMN was determined from a 15-minute resting state functional magnetic resonance imaging (fMRI), and network properties were calculated using standard graph-theoretical measures.

RESULTS

More severe deficits of verbal abilities tended to be associated with an earlier age at epilepsy onset, but were not directly related to the number of seizures and disease duration. Nonetheless, at the network level, disease duration was associated with alterations of the efficiency and centrality of parietal network nodes and midline structures. Particularly, centrality of the left inferior parietal lobe (IPL) was found to be linked with CD. Reduced centrality of the left IPL and alterations supporting a rather segregated processing within DMN's subsystems was associated with a more favorable CD. A more complicated SED was associated with high seizure frequency and long disease duration, and revealed links with a less favorable CD.

SIGNIFICANCE

An impaired CD and - because of their interrelation - SED might be mediated by a common pathomechanism reflected in an aberrant organization, and thus, a potential functional deficit of the DMN. A functional segregation of (left) parietal network nodes from the DMN and a rather segregated processing mode within the DMN might have positive implications/protective value for CD in patients with RE.

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.

"Atypical forms" of benign epilepsy with centrotemporal spikes (BECTS): How to diagnose and guide these children. A practical/scientific approach

Benign epilepsy with centrotemporal spikes (BECTS) epilepsy, also known as rolandic epilepsy, is the most common childhood type of epilepsy. There is debate on its "benign" definition given the numerous literature data on its correlation to cognitive morbidity. Although its prognosis is often favorable, BECTS can present or evolve however to an atypical form, characterized by a worse prognosis and negative impact on cognitive development. It is possible that abnormal electrical activity, marker of neurological dysfunction, has the potential to disrupt neural network function and development. Numerous studies tried to identify clinical or electroencephalographic criteria for atypical forms and atypical evolution of BECTS in order to guide follow-up and treatment of patients and to predict their outcome. This review provides a compact summery of literature data with a focus on predictive features of future cognitive decline.

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.

Neurorehabilitation with FORAMENRehab for attention impairment in children with epilepsy

Epilepsy is a frequent neurological disorder in children and often accompanied with attention impairment. Still, few systematically controlled rehabilitation techniques for children exist. The aim of this study was to design and measure the impact of the FORAMENRehab computer-based intervention method for attention impairment rehabilitation in children with epilepsy. We chose the FORAMENRehab program because it allows separate training for different attention components based on individual needs. Forty-eight children participated in the study. At baseline, all patients underwent neuropsychological examination of attention with the NEPSY test battery. The study group consisted of 17 8- to 12-year-old children with partial epilepsy and attention impairment who received neurorehabilitation over 5weeks (10 sessions) with FORAMENRehab Attention module accompanied by a therapist. Two control groups were included: the first control group of 12 children with partial epilepsy and attention impairment (waiting-list) participated in assessments with baseline tasks before and after the five-week period and received no active training. Additionally, all patients participated in the follow-up assessment 1.31years later. The second control group consisted of 19 typically developing children who only participated in the first assessment. After the intervention, study group patients showed significant improvement in complex attention and tracking (P<0.025). To achieve the effect of intervention in children with partial epilepsy, 10 sessions tailored to individual levels of ability were the minimum. Three attention components - sustained, complex, and tracking - need selective and longer training for more effective remediation. Follow-up assessment revealed a long-term positive effect of intervention. After 1.31years, the study group had significantly improved in three out of the four attention components (P<0.025), whereas the waiting-list group showed improvement in only two aspects of one complex attention component. In conclusion, attention impairment rehabilitation with FORAMENRehab is effective for children with epilepsy. Rehabilitation should focus on training specific components of attention and follow an individual-based rehabilitation process.

Attention deficits in children with epilepsy: Preliminary findings

OBJECTIVE

Attention difficulties are a common clinical complaint among children with epilepsy. We aimed to compare a range of attentional abilities between groups of children with two common epilepsy syndromes, Temporal Lobe Epilepsy (TLE) and Idiopathic Generalized Epilepsy (IGE), and to healthy controls. We also investigated whether epilepsy factors (laterality of seizure focus, epilepsy onset, duration, and severity) were related to attentional abilities.

METHODS

Multiple dimensions of attention (selective, sustained, and divided attention and attentional control) were assessed directly with standardized neuropsychological measures in 101 children aged 6-16years (23 children with TLE, 20 with IGE and 58 healthy controls). Attention was also assessed indirectly, via a parent-report measure.

RESULTS

Children with TLE performed worse than children with IGE (p=0.013) and healthy controls (p<0.001) on a test of attentional control, but no between-group differences were apparent on tests of other attentional abilities. Compared to healthy controls, greater attention problems were reported by parents of children with TLE (p=0.006) and IGE (p=0.012). Left-hemisphere seizure focus and greater epilepsy severity were associated with poorer attentional control and sustained-divided attention, respectively, but no other epilepsy factors were associated with attentional abilities.

SIGNIFICANCE

These findings suggest that children with localization-related epilepsy, but not generalized epilepsy, may be at risk of deficits in attentional control. Interventions aimed at improving attentional control may be targeted at children with localization-related epilepsy, particularly those with a left-hemisphere seizure focus, who appear to be particularly susceptible to this type of attentional deficit.

Atypical Benign Epilepsy of Childhood With Rolandic Spikes: Features of a Subset Requiring More Than One Medication for Seizure Control

The objective of this study was to compare the clinical and electrographic features of two groups of children with benign epilepsy of childhood with rolandic spikes: those in whom seizure control was attained either without the use of medication or with a single medication (group1) and those requiring two medications for seizure control (group 2). A consecutive series of children with benign epilepsy of childhood with rolandic spikes were identified in a single pediatric neurology practice. Medical charts were then systematically retrospectively reviewed. A total of 66 children with benign epilepsy of childhood with rolandic spikes were identified; 52 (78.8%) required either no medication ( n = 7) or a single medication ( n = 45) for seizure control, whereas 14 (21.2%) required two medications. The two groups did not differ with respect to gender, age of onset, type (generalized or partial) of initial seizure, or whether EEG abnormalities were unilateral or bilateral. They did differ significantly with respect to the mean number of seizures experienced prior to initiating treatment (group 1, 2.06, versus group 2, 4.36; t = 3.40, P = .005). In those treated ( n = 59), the initial medication selected (carbamazepine versus noncarbamazepine) in the two groups was significantly different: group 1, 40 (carbamazepine)/45, versus group 2, 9 (carbamazepine)/14; χ 2 = 4.59; P = .03. The difference in frequency between the two groups of associated comorbid conditions (tics, attention-deficit hyperactivity disorder [ADHD], learning disability) almost reached the threshold of statistical significance: group 1, 7/52, versus group 2, 5/14 (χ2 = 3.67, P = .06). A subset of children with benign epilepsy of childhood with rolandic spikes may require more than one medication for effective seizure control. This subset experiences more seizures prior to the initiation of treatment, is more likely to be treated initially with a noncarbamazepine medication, and tends to have a higher frequency of associated conditions. ( J Child Neurol 2002; 17: 900—903).

New genes for focal epilepsies with speech and language disorders

The last 2 years have seen exciting advances in the genetics of Landau-Kleffner syndrome and related disorders, encompassed within the epilepsy-aphasia spectrum (EAS). The striking finding of mutations in the N-methyl-D-aspartate (NMDA) receptor subunit gene GRIN2A as the first monogenic cause in up to 20% of patients with EAS suggests that excitatory glutamate receptors play a key role in these disorders. Patients with GRIN2A mutations have a recognizable speech and language phenotype that may assist with diagnosis. Other molecules involved in RNA binding and cell adhesion have been implicated in EAS; copy number variations are also found. The emerging picture highlights the overlap between the genetic determinants of EAS with speech and language disorders, intellectual disability, autism spectrum disorders and more complex developmental phenotypes.