Correlation between Cognition and Behavior in Epilepsy

Psychiatric disorders in children and adolescents with temporal lobe epilepsy: A narrative review

People with epilepsy (PWE) are at higher risk of psychiatric disorders (PD), disability, and reduced quality of life than the general population, especially in childhood and adolescence and when seizures originate from the temporal lobe. Temporal Lobe Epilepsy (TLE) is the most common type of focal epilepsy and can be due to structural abnormalities, or non-lesional causes, such as genetic variants. The prevalence of PD is approximately 20%-30% in people with epilepsy in general, and from 40% up to 80% in people with TLE. A higher rate of anxiety and depression disorders has been observed in association with TLE than with extra-temporal epilepsy, or idiopathic generalized epilepsy, or other chronic diseases such as diabetes. However, while the association between psychopathology and TLE has been extensively assessed in adults, only a few studies have focused on its expression in children and adolescents. In this review, we describe the prevalence, characteristics, and risk factors for PD in people with epilepsy in general and with TLE, with a specific focus on the pediatric age. In addition, we provide insights into the current knowledge of the pathophysiological bases of psychiatric symptoms in children and adolescents with TLE. PLAIN LANGUAGE SUMMARY: This review examines the frequency and characteristics of psychiatric disorders in people with temporal lobe epilepsy, with a focus on children and adolescents. Similarly to adults, younger people with epilepsy have higher rates of psychiatric disorders, such as depression and anxiety, than healthy peers or children with other chronic illnesses such as diabetes and asthma. Contributing risk factors include epilepsy duration and severity, and the effects of antiseizure medications, as well as psychological challenges, sociocultural influences, and family dynamics. Psychiatric disorders associated with temporal lobe epilepsy are relatively frequent, probably in relation to the critical role that some limbic structures in the temporal lobe, such as the amygdala and hippocampus, play in regulating emotions and behavior.

Association of synaptic density and cognitive performance in temporal lobe epilepsy: Humans and animals PET imaging study with [18F]SynVesT-1

AIM

Cognitive impairment is a common comorbidity in individuals with temporal lobe epilepsy (TLE), yet the underlying mechanisms remain unknown. This study explored the putative association between in vivo synaptic loss and cognitive outcomes in TLE patients by PET imaging of synaptic vesicle glycoprotein 2A (SV2A).

METHODS

We enrolled 16 TLE patients and 10 cognitively normal controls. All participants underwent SV2A PET imaging using [18F]SynVesT-1 and cognitive assessment. Lithium chloride-pilocarpine-induced rats with status epilepticus (n = 20) and controls (n = 6) rats received levetiracetam (LEV, specifically binds to SV2A), valproic acid (VPA), or saline for 14 days. Then, synaptic density was quantified by [18F]SynVesT-1 micro-PET/CT. The novel object recognition and Morris water maze tests evaluated TLE-related cognitive function. SV2A expression was examined and confirmed by immunohistochemistry.

RESULTS

Temporal lobe epilepsy patients showed significantly reduced synaptic density in hippocampus, which was associated with cognitive performance. In the rat model of TLE, the expression of SV2A and synaptic density decreased consistently in a wider range of brain regions, including the entorhinal cortex, insula, hippocampus, amygdala, thalamus, and cortex. We treated TLE animal models with LEV or VPA to explore whether synaptic loss contributes to cognitive deficits. It was found that LEV significantly exerted protective effects against brain synaptic deficits and cognitive impairment.

CONCLUSION

This is the first study to link synaptic loss to cognitive deficits in TLE, suggesting [18F]SynVesT-1 PET could be a promising biomarker for monitoring synaptic loss and cognitive dysfunction. LEV might help reverse synaptic deficits and ameliorate learning and memory impairments in TLE patients.

On-demand low-frequency stimulation for seizure control: efficacy and behavioural implications

Mesial temporal lobe epilepsy (MTLE), the most common form of focal epilepsy in adults, is often refractory to medication and associated with hippocampal sclerosis. Deep brain stimulation represents an alternative treatment option for drug-resistant patients who are ineligible for resective brain surgery. In clinical practice, closed-loop stimulation at high frequencies is applied to interrupt ongoing seizures, yet has (i) a high incidence of false detections; (ii) the drawback of delayed seizure-suppressive intervention; and (iii) limited success in sclerotic tissue. As an alternative, low-frequency stimulation (LFS) has been explored recently in patients with focal epilepsies. In preclinical epilepsy models, hippocampal LFS successfully prevented seizures when applied continuously. Since it would be advantageous to reduce the stimulation load, we developed a protocol for on-demand LFS. Given the importance of the hippocampus for navigation and memory, we investigated potential consequences of LFS on hippocampal function. To this end, we used the intrahippocampal kainate mouse model, which recapitulates the key features of MTLE, including spontaneous seizure activity and hippocampal sclerosis. Specifically, our online detection algorithm monitored epileptiform activity in hippocampal local field potential recordings and identified short epileptiform bursts preceding focal seizure clusters, triggering hippocampal LFS to stabilize the network state. To probe behavioural performance, we tested the acute influence of LFS on anxiety-like behaviour in the light-dark box test, spatial and non-spatial memory in the object location memory and novel object recognition test, as well as spatial navigation and long-term memory in the Barnes maze. On-demand LFS was almost as effective as continuous LFS in preventing focal seizure clusters but with a significantly lower stimulation load. When we compared the behavioural performance of chronically epileptic mice to healthy controls, we found that both groups were equally mobile, but epileptic mice displayed an increased anxiety level, altered spatial learning strategy and impaired memory performance. Most importantly, with the application of hippocampal LFS before behavioural training and test sessions, we could rule out deleterious effects on cognition and even show an alleviation of deficits in long-term memory recall in chronically epileptic mice. Taken together, our findings may provide a promising alternative to current therapies, overcoming some of their major limitations, and inspire further investigation of LFS for seizure control in focal epilepsy syndromes.

Exploring behavioral systems of the reinforcement sensitivity theory in people with epilepsy: A cross-sectional study

OBJECTIVES

Although epilepsy has previously been associated with behavioral changes, no previous study has utilized the behavioral models of the reinforcement sensitivity theory (RST) to investigate the impact of epilepsy on behavior. Therefore, the objective of this cross-sectional study is to examine the potential relationship between epilepsy and the neurobehavioral systems of the RST.

METHODS

Using the Reinforcement Sensitivity Theory-Personality Questionnaire (RST-PQ), this cross-sectional study assessed the behavioral systems of the RST in a sample of 27 epilepsy patients and 27 age- and gender-matched healthy individuals. The RST-PQ was designed to assess the different behavioral systems of the RST. The behavioral approach system (BAS) is responsible of the approach behavior, in high values related to risk seeking and addictive behavior and in low values well related to depression. The behavioral inhibition system (BIS) is well related to anxiety in high levels, and the fight flight freeze system (FFFS) is responsible for the avoidance behavior.

RESULTS

After adjusting for age, no significant differences were found in demographic information (gender and marital status) between the general population and epilepsy patients. Gender distribution was similar, with 55.6% females in both groups. Marital status also showed no significant difference, with 74% single in the control group and 63% in the epilepsy group. Significant differences were observed in the behavioral systems of the RST. The epilepsy group had higher scores compared with the control group in several areas. BAS reward activity had a median score of 23 in the epilepsy group and 21 in the control group (p = 0.001). BAS goal drive persistence (p = 0.04), BAS impulsivity (p = 0.014), FFFS (p = 0.002), and BIS (median score of 77 in the epilepsy group and 66 in the control group) also showed significant differences, with p = 0.001. These significant differences remained consistent before and after matching the control group, indicating their robustness. The only exception was BAS reward activity, which did not show a significant difference after matching, with p = 0.106 and p = 0.051 before and after matching, respectively.

CONCLUSIONS

The study suggests a potential positive association between epilepsy and the BIS, potentially mediated by the hippocampus. The relationship between epilepsy and the BAS, as well as the FFFS, may also be influenced by the BIS. These findings have clinical implications, but further research is needed to confirm these relationships.

Neurotoxicity of Silver Nanoparticles and Non-Linear Development of Adaptive Homeostasis with Age

For the first time in the world, the behavioral functions of laboratory mammals exposed to silver nanoparticles were studied with regard to age. Silver nanoparticles coated with polyvinylpyrrolidone with a size of 8.7 nm were used in the present research as a potential xenobiotic. Elder mice adapted to the xenobiotic better than the younger animals. Younger animals demonstrated more drastic anxiety than the elder ones. A hormetic effect of the xenobiotic in elder animals was observed. Thus, it is concluded that adaptive homeostasis non-linearly changes with age increase. Presumably, it may improve during the prime of life and start to decline just after a certain stage. This work demonstrates that age growth is not directly conjugated with the organism fading and pathology development. Oppositely, vitality and resistance to xenobiotics may even improve with age at least until the prime of life.

Therapeutic Potential of Quercetin and its Derivatives in Epilepsy: Evidence from Preclinical Studies

Quercetin is a polyphenolic bioactive compound highly enriched in dietary fruits, vegetables, nuts, and berries. Quercetin and its derivatives like rutin and hyperoside are known for their beneficial effects in various neurological conditions including epilepsy. The clinical studies of quercetin and its derivatives in relation to epilepsy are limited. This review provides the evidence of most recent knowledge of anticonvulsant properties of quercetin and its derivatives on preclinical studies. Additionally, the studies demonstrating antiseizure potential of various plants extracts enriched with quercetin and its derivatives has been included in this review. Herein, we have also discussed neuroprotective effect of these bioactive compound and presented underlying mechanisms responsible for anticonvulsant properties in brief. Finally, limitations of quercetin and its derivatives as antiseizure compounds as well as possible strategies to enhance efficacy have also been discussed.

Visual Motor and Executive Functioning in Adult Patients with Primary Generalized Epilepsy: A Pilot Study

Background and Purpose

Epilepsy is a neuropsychological disorder which can lead to various cognitive deficits of varying levels. Primary generalized epilepsy is characterized by bilateral ictal electroencephalography patterns and excessive neural activity found in both hemispheres of the brain. There is dearth of research on primary generalized epilepsy in adult population. The present study investigates the visual motor and executive functioning deficits in patients with primary generalized epilepsy.

Methods

Study was conducted on 30 participants (n=30) divided into target and normal control group. Target group consisted of patients diagnosed with primary generalized epilepsy with minimum 5 years of illness. Bender-Gestalt test (BGT) and Wisconsin's Card Sorting Test (WCST) was administered on both the groups.

Results

A significant difference was found between target group and control group's performances on BGT which indicates that visual motor functioning of control group was better than target group. A significant difference in executive functioning was found in performance of epilepsy patients and non-patients on the domains of WCST.

Conclusions

Both executive and visuomotor functioning are significantly affected in patients of primary generalized epilepsy in adult patients.

Dynamic Temporospatial Patterns of Functional Connectivity and Alterations in Idiopathic Generalized Epilepsy

The dynamic profile of brain function has received much attention in recent years and is also a focus in the study of epilepsy. The present study aims to integrate the dynamics of temporal and spatial characteristics to provide comprehensive and novel understanding of epileptic dynamics. Resting state fMRI data were collected from eighty-three patients with idiopathic generalized epilepsy (IGE) and 87 healthy controls (HC). Specifically, we explored the temporal and spatial variation of functional connectivity density (tvFCD and svFCD) in the whole brain. Using a sliding-window approach, for a given region, the standard variation of the FCD series was calculated as the tvFCD and the variation of voxel-wise spatial distribution was calculated as the svFCD. We found primary, high-level, and sub-cortical networks demonstrated distinct tvFCD and svFCD patterns in HC. In general, the high-level networks showed the highest variation, the subcortical and primary networks showed moderate variation, and the limbic system showed the lowest variation. Relative to HC, the patients with IGE showed weaken temporal and enhanced spatial variation in the default mode network and weaken temporospatial variation in the subcortical network. Besides, enhanced temporospatial variation in sensorimotor and high-level networks was also observed in patients. The hyper-synchronization of specific brain networks was inferred to be associated with the phenomenon responsible for the intrinsic propensity of generation and propagation of epileptic activities. The disrupted dynamic characteristics of sensorimotor and high-level networks might potentially contribute to the driven motion and cognition phenotypes in patients. In all, presently provided evidence from the temporospatial variation of functional interaction shed light on the dynamics underlying neuropathological profiles of epilepsy.

Self-injurious behavior in epilepsy

Self-injurious behavior (SIB) can be described as an act involving self-inflicted destruction of tissue, right away or over a period of time. Patients with epilepsy have to deal with an often chronic and unpredictable disorder leading to adversity in many psychosocial variables such as employment, stigma, and overall quality of life. The above factors contribute toward SIB in these patients. Behavioral problems occurring in people with epilepsy can range from aggressiveness, mood fluctuations to SIB. We report a 23-year-old male, married, educated up to 10^th standard, referred from neurology department for psychiatric evaluation. The patient had gone to neurologist with the chief complaints of generalized tonic-clonic convulsions and was hospitalized for breakthrough seizure. There was a history of indulging in episodes of self-SIB since the past 8 months. He responded satisfactorily to adjustment of antiepileptic medication along with fluoxetine and low-dose risperidone. Early identification of such behavior in epilepsy patients should be done so that a holistic management is undertaken leading to better functioning and improved quality of life.

A Proline Derivative-Enriched Fraction from Sideroxylon obtusifolium Protects the Hippocampus from Intracerebroventricular Pilocarpine-Induced Injury Associated with Status Epilepticus in Mice

The N-methyl-(2S,4R)-trans-4-hydroxy-l-proline-enriched fraction (NMP) from Sideroxylon obtusifolium was evaluated as a neuroprotective agent in the intracerebroventricular (icv) pilocarpine (Pilo) model. To this aim, male mice were subdivided into sham (SO, vehicle), Pilo (300 µg/1 µL icv, followed by the vehicle per os, po) and NMP-treated groups (Pilo 300 µg/1 µL icv, followed by 100 or 200 mg/kg po). The treatments started one day after the Pilo injection and continued for 15 days. The effects of NMP were assessed by characterizing the preservation of cognitive function in both the Y-maze and object recognition tests. The hippocampal cell viability was evaluated by Nissl staining. Additional markers of damage were studied-the glial fibrillary acidic protein (GFAP) and the ionized calcium-binding adaptor molecule 1 (Iba-1) expression using, respectively, immunofluorescence and western blot analyses. We also performed molecular docking experiments revealing that NMP binds to the γ-aminobutyric acid (GABA) transporter 1 (GAT1). GAT1 expression in the hippocampus was also characterized. Pilo induced cognitive deficits, cell damage, increased GFAP, Iba-1, and GAT1 expression in the hippocampus. These alterations were prevented, especially by the higher NMP dose. These data highlight NMP as a promising candidate for the protection of the hippocampus, as shown by the icv Pilo model.

Effects of Dexamethasone on Remodeling of the Hippocampal Synaptic Filamentous Actin Cytoskeleton in a Model of Pilocarpine-induced Status Epilepticus

The filamentous actin (F-actin) cytoskeleton is progressively damaged after status epilepticus (SE), which is related to delayed neuronal death, aberrant recurrent circuits and epileptogenesis. Glucocorticoids regulate dendritic spine remodeling by acting on glucocorticoid receptors and the dynamics of the F-actin cytoskeleton. Our previous study showed that administration of dexamethasone (DEX) in the latent period of the pilocarpine epileptic model reduces damage to the hippocampal filamentous actin cytoskeleton and the loss of hippocampal neurons and aids in maintaining the synaptic structures, but it is not sufficient to stop epileptogenesis. In this work, we focused on the role of glucocorticoids in regulating the hippocampal F-actin cytoskeleton during SE. We examined the abundance of synaptic F-actin, analyzed the hippocampal F-actin/G-actin (F/G) ratio and pCofilin, and evaluated the number of hippocampal neurons and pre/postsynaptic markers in pilocarpine-induced status epilepticus mice with or without administration of dexamethasone (DEX). We found that the latency of Stage 3 seizures increased, the mortality decreased, the damage to the synaptic F-actin cytoskeleton in the hippocampal subfields was significantly attenuated, and a greater number of postsynaptic structures were retained in the hippocampal subfields after treatment with DEX. These results indicate that treatment with dexamethasone stabilizes the synaptic F-actin cytoskeleton and reduces the damage to the brain due to SE. This approach is expected to be beneficial in alleviating delayed neuron damage and the process of epileptogenesis.

Sleep disorders and behavioral disorders in Jamaican children with epilepsy: A case-control study

Children with epilepsy (CWE) are more likely to have sleep and behavioral disorders. With differences in reports, the aim was to evaluate sleep and behavior in Jamaican CWE and determine any association with epilepsy-related variables. Children with epilepsy were identified along with age and gender-matched controls from the University Hospital of the West Indies and the Bustamante Hospital for Children. Written informed consent was obtained followed by the completion of questionnaires assessing sleep, behavior, and background of both cases and controls. Parents of 61 children (26 cases and 35 controls) participated in the study. There was no difference in sleep scores or frequency of sleep disorders between cases and controls (p > 0.05). Children with epilepsy had worse scores than controls in peer problems (3.85 vs 2.32, p < 0.01), internal problems (7.42 vs 4.71, p < 0.01), and total behavioral problem (16.27 vs 12.09, p < 0.01). When compared with controls, CWE had a higher frequency of abnormal peer problems (66% vs 32%, p < 0.05) and emotional problems score (42% vs 15%, p < 0.05). Children with learning difficulty were three times more likely to have abnormal behavioral score Odds Ratio (OR) = 3.818, p < 0.05). Jamaican CWE have similar sleep scores to their healthy peers but have a higher frequency of peer and emotional problems.

Social cognition, behaviour and therapy adherence in frontal lobe epilepsy: a study combining neuroeconomic and neuropsychological methods

Social behaviour of healthy humans and its neural correlates have been extensively studied in social neuroscience and neuroeconomics. Whereas it is well established that several types of epilepsies, such as frontal lobe epilepsy, lead to social cognitive impairments, experimental evidence on how these translate into behavioural symptoms is scarce. Furthermore, it is unclear whether social cognitive or behavioural disturbances have an impact on therapy adherence, which is critical for effective disease management, but generally low in these patients. In order to investigate the relationship between social cognition, social behaviour, and therapy adherence in patients with frontal lobe epilepsies (FLE), we designed a study combining conventional neuropsychological with behavioural economic and functional magnetic resonance imaging (fMRI) methodology. Fifteen patients and 15 healthy controls played a prisoners' dilemma game (an established game to operationalize social behaviour) while undergoing fMRI. Additionally, social cognitive, basic neuropsychological variables, and therapy adherence were assessed. Our results implicate that social behaviour is indeed affected and can be quantified using neuroeconomic methods in patients with FLE. Impaired social behaviour in these patients might be a consequence of altered brain activation in the medial prefrontal cortex and play a role in low therapy adherence. Finally, this study serves as an example of how to integrate neuroeconomic methods in neurology.

Effects of Histone Deacetylase Inhibitors on the Development of Epilepsy and Psychiatric Comorbidity in WAG/Rij Rats

Epigenetic mechanisms, such as alterations in histone acetylation based on histone deacetylases (HDACs) activity, have been linked not only to normal brain function but also to several brain disorders including epilepsy and the epileptogenic process. In WAG/Rij rats, a genetic model of absence epilepsy, epileptogenesis and mild-depression comorbidity, we investigated the effects of two HDAC inhibitors (HDACi), namely sodium butyrate (NaB), valproic acid (VPA) and their co-administration, on the development of absence seizures and related psychiatric/neurologic comorbidities following two different experimental paradigms. Treatment effects have been evaluated by EEG recordings (EEG) and behavioural tests at different time points. Prolonged and daily VPA and NaB treatment, started before absence seizure onset (P30), significantly reduced the development of absence epilepsy showing antiepileptogenic effects. These effects were enhanced by NaB/VPA co-administration. Furthermore, early-chronic HDACi treatment improved depressive-like behaviour and cognitive performance 1 month after treatment withdrawal. WAG/Rij rats of 7 months of age showed reduced acetylated levels of histone H3 and H4, analysed by Western Blotting of homogenized brain, in comparison to WAG/Rij before seizure onset (P30). The brain histone acetylation increased significantly during treatment with NaB or VPA alone and more markedly during co-administration. We also observed decreased expression of both HDAC1 and 3 following HDACi treatment compared to control group. Our results suggest that histone modifications may have a crucial role in the development of epilepsy and early treatment with HDACi might be a possible strategy for preventing epileptogenesis also affecting behavioural comorbidities.

Envisioning the neuroprotective effect of Metformin in experimental epilepsy: A portrait of molecular crosstalk

Epilepsy is a neurological disorder characterized by an enduring predisposition to generate and aggravate epileptic seizures affecting around 1% of global population making it a serious health concern. Despite the recent advances in epilepsy research, no disease-modifying treatment able to terminate epileptogenesis have been reported yet reflecting the complexity in understanding the disease pathogenesis. To overcome the current treatment gap against epilepsy, one effective approach is to explore anti-epileptic effects from a drug that are approved to treat non-epileptic diseases. In this regard, Metformin emerged as an ideal candidate which is a first line treatment option for type 2 diabetes mellitus (T2DM), has conferred neuroprotection in several in vivo neurological disorders such as Alzheimer's diseases (AD), Parkinson's disease (PD), Stroke, Huntington's diseases (HD) including epilepsy. In addition, Metformin has ameliorated cognitive alteration, learning and memory induced by epilepsy as well as in animal model of AD. Herein, we review the promising findings demonstrated upon Metformin treatment against animal model of epilepsy however, the precise underlying mechanism of anti-epileptic potential of Metformin is not well understood. However, there is a growing understanding that Metformin demonstrates its anti-epileptic effect mainly via ameliorating brain oxidative damage, activation of AMPK, inhibition of mTOR pathway, downregulation of α-synuclein, reducing apoptosis, downregulation of BDNF and TrkB level. These reflects that Metformin being non-anti-epileptic drug (AED) has a potential to ameliorate the cellular pathways that were impaired in epilepsy reflecting its therapeutical potential against epileptic seizure that might plausibly overcome the limitations of today epilepsy treatment.

Internalizing and externalizing symptoms in preschool and school-aged children with epilepsy: Focus on clinical and EEG features

INTRODUCTION

Psychiatric and behavioral problems are frequent comorbidities of epilepsy, although their clinical and electroencephalographic (EEG) correlates remain uncertain. In this study, we have assessed the frequency of psychopathological problems in a cohort of children with epilepsy, and established their main clinical and EEG-associated features.

METHODS

One hundred fifty-nine young patients with epilepsy were recruited and assessed through the Child Behavior Checklist for preschool-aged children (CBCL 1 1/2-5) or for school-aged children (CBCL 6-18). Child Behavior Checklist (CBCL) results were then correlated to the main clinical and EEG data.

RESULTS

We found emotional and behavioral problems in about half of the children in our sample. Internalizing, social, and attention problems were more common than externalizing features. Moderate intellectual disability, a nonidiopathic etiology of epilepsy, a poor control of seizures, and antiepileptic polytherapies, as well as an early age at seizure-onset and a longer duration of the disorder, were all associated with specific behavioral and emotional problems. A temporal site of interictal EEG abnormalities also enhanced the risk for psychiatric comorbidities, especially in the externalizing domain.

CONCLUSIONS

Several clinical and EEG features are associated with an increased risk for emotional and behavioral comorbidities in children with epilepsy. Their identification may foster an early diagnosis and appropriate care, limiting the worsening of psychiatric symptoms and their impact on quality of life and health status. A better understanding of the underlying clinical and molecular mechanisms is needed to further improve prevention and treatment interventions.

Analytic information processing style in epilepsy patients

Relevant to the study of epileptogenesis is learning processing, given the pivotal role that neuroplasticity assumes in both mechanisms. Recently, evoked potential analyses showed a link between analytic cognitive style and altered neural excitability in both migraine and healthy subjects, regardless of cognitive impairment or psychological disorders. In this study we evaluated analytic/global and visual/auditory perceptual dimensions of cognitive style in patients with epilepsy. Twenty-five cryptogenic temporal lobe epilepsy (TLE) patients matched with 25 idiopathic generalized epilepsy (IGE) sufferers and 25 healthy volunteers were recruited and participated in three cognitive style tests: "Sternberg-Wagner Self-Assessment Inventory", the C. Cornoldi test series called AMOS, and the Mariani Learning style Questionnaire. Our results demonstrate a significant association between analytic cognitive style and both IGE and TLE and respectively a predominant auditory and visual analytic style (ANOVA: p values <0,0001). These findings should encourage further research to investigate information processing style and its neurophysiological correlates in epilepsy.

The relationship of seizure focus with depression, anxiety, and health-related quality of life in children and adolescents with epilepsy

For youth with epilepsy, comorbid psychiatric conditions, such as depression and anxiety, require further examination as they carry increased risk for reduced health-related quality of life (HRQOL). The current study assessed whether rates of depression, anxiety, and withdrawal behaviors differed based on seizure location. Data included parental ratings on the Behavior Assessment System for Children (BASC-2) and the Quality of Life in Childhood Epilepsy (QOLCE) questionnaire for 132 children and adolescents (mean age=11.34, SD=3.95) with generalized or partial (i.e., frontal [FLE] or temporal lobe epilepsy [TLE]) epilepsy. Our results identified clinically significant internalizing psychopathology in nearly half of our sample (41%). Although rates of internalizing behavior were similar between generalized and partial groups, children and adolescents with TLE demonstrated higher rates of depression compared to youth with FLE. No effects of laterality on internalizing behaviors were identified between TLE and FLE groups. Finally, for youth with TLE, parental depression ratings along with current number of antiepileptic medications (AEDs) were found to be significant barriers to HRQOL above and beyond anxiety, withdrawal, and epilepsy-specific variables. Temporal lobe epilepsy was associated with a two-fold risk of clinically significant depression ratings. These findings highlight the high prevalence of internalizing psychopathology features in pediatric epilepsy and offer further support for the relationship between depression and TLE in children and adolescents with epilepsy.

Cognitive Function and Heat Shock Protein 70 in Children With Temporal Lobe Epilepsy

We conducted the present study to examine cognitive function and serum heat shock protein 70 levels among children with temporal lobe epilepsy. The Stanford-Binet Intelligence Test was carried out to examine cognitive function in 30 children with temporal lobe epilepsy and 30 controls. Serum heat shock protein 70 levels were determined with an enzyme-linked immunosorbent assay. The epilepsy group had significantly lower cognitive function testing scores and significantly higher serum heat shock protein 70 levels than the control group; there were significant negative correlations between serum heat shock protein 70 levels and short-term memory and composite scores. Children with uncontrolled seizures had significantly lower verbal reasoning scores and significantly higher serum heat shock protein 70 levels than children with controlled seizures. Children with temporal lobe epilepsy have cognitive dysfunction and elevated levels of serum heat shock protein 70, which may be considered a stress biomarker.

Psychopathology in adolescents with TLE and FLE

BACKGROUND

To describe the rates and types of psychiatric disorders among adolescents with chronic symptomatic epilepsies and to evaluate syndrome-specific differences between temporal lobe (TLE) and frontal lobe (FLE) epilepsies.

METHODS

A cross-sectional single-center study design applying the Youth Self Report (YSR) to investigate psychopathological symptoms and the Weinberger Adjustment Inventory (WAI) to investigate personality dimensions was used. Consecutive adolescents between 14 and 18 years of age with drug-resistant symptomatic TLE and FLE were investigated during pre-surgical evaluation prior to epilepsy surgery. Data from twenty-eight patients (19 with TLE and 9 with FLE) were analyzed for this report.

RESULTS

Compared with the test norm, higher prevalence rates and a wider range of psychopathological symptoms were seen in patients with TLE. This result was not seen in patients with FLE. Concerning personality dimensions, significantly higher values of repressive defensiveness and significantly lower values of positive emotion and confidence were found in patients with TLE. In contrast, significantly lower levels of distress and significantly higher levels of repressive defensiveness and denial of distress were seen in patients with FLE. Comparing TLE with FLE, a significantly higher mean score for distress, and a significantly lower mean score for positive emotion and denial of distress were found in patients with TLE.

CONCLUSION

In summary, psychiatric comorbidity was frequently found in this sample of youths with chronic drug-resistant localization-related epilepsies. Although results have to be interpreted with caution because of the small sample size, psychiatric symptomatology was significantly different between TLE and FLE. Our results show that continuous and syndrome-specific psychiatric monitoring is essential in young patients with epilepsy.

Time course evaluation of behavioral impairments in the pilocarpine model of epilepsy

Epilepsy is a brain function disorder characterized by unpredictable and recurrent seizures. The majority of patients with temporal lobe epilepsy (TLE), which is the most common type of epilepsy, have to live not only with seizures but also with behavioral alterations, including anxiety, psychosis, depression, and impaired cognitive functioning. The pilocarpine model has been recognized as an animal model of TLE. However, there are few studies addressing behavioral alterations in the maturation phase when evaluating the time course of the epileptogenic process after pilocarpine administration. Therefore, the present work was designed to analyze the neurobehavioral impairments of male adult Wistar rats during maturation and chronic phases in the pilocarpine model of epilepsy. Behavioral tests included: open-field tasks, olfactory discrimination, social recognition, elevated plus maze, and the forced swimming test. The main behavioral alterations observed in both maturation and chronic phases of the pilocarpine model were olfactory and short-term social memory deficits and decrease in the immobility time in the forced swimming test. Moreover, increased anxiety-like responses were only observed in the maturation phase. These findings indicate that early behavioral impairments can be observed in the pilocarpine model during the maturation phase, and these behavioral deficits also occur during the acquired epilepsy (chronic phase). Several of the neurobehavioral impairments that are associated with epilepsy in humans were observed in the pilocarpine-treated rats, thus, rendering this animal model a useful tool to study neuroprotective strategies as well as neurobiological and psychopathological mechanisms associated with epileptogenesis.

Ultrasound stimulation inhibits recurrent seizures and improves behavioral outcome in an experimental model of mesial temporal lobe epilepsy

Current therapies for epilepsy consist mostly of pharmacological agents or invasive surgery. Recently, ultrasound (US) stimulation has been considered a promising tool for the noninvasive treatment of brain diseases, including epilepsy. However, in temporal lobe epilepsy (TLE), a common form of epilepsy, neurophysiological and functional outcomes following US stimulation are not well defined. To address this, we developed a paradigm of transcranial pulsed US stimulation to efficiently suppress seizure activity in the initial/acute period in a kainate (KA)-induced mouse model of mesial TLE. Pulsed US stimulation inhibited acute seizure activity and either delayed the onset of or suppressed status epilepticus (SE). Kainate-treated mice that had received US stimulation in the initial period exhibited fewer spontaneous recurrent seizures (SRSs) and improved performance in behavioral tasks assessing sociability and depression in the chronic period of epilepsy. Our results demonstrate that US stimulation in the acute period of epilepsy can inhibit SRSs and improve behavioral outcomes in a mouse model of mesial TLE. The present study suggests that noninvasive transcranial pulsed US stimulation may be feasible as an adjuvant therapy in patients with epilepsy. This article is part of a Special Issue entitled "Status Epilepticus".

Impaired neuronal operation through aberrant intrinsic plasticity in epilepsy

OBJECTIVE

Patients with temporal lobe epilepsy often display cognitive comorbidity with recurrent seizures. However, the cellular mechanisms underlying the impairment of neuronal information processing remain poorly understood in temporal lobe epilepsy. Within the hippocampal formation neuronal networks undergo major reorganization, including the sprouting of mossy fibers in the dentate gyrus; they establish aberrant recurrent synapses between dentate granule cells and operate via postsynaptic kainate receptors. In this report, we tested the hypothesis that this aberrant local circuit alters information processing of perforant path inputs constituting the major excitatory afferent pathway from entorhinal cortex to dentate granule cells.

METHODS

Experiments were performed in dentate granule cells from control rats and rats with temporal lobe epilepsy induced by pilocarpine hydrochloride treatment. Neurons were recorded in patch clamp in whole cell configuration in hippocampal slices.

RESULTS

Our present data revealed that an aberrant readout of synaptic inputs by kainate receptors triggered a long-lasting impairment of the perforant path input-output operation in epileptic dentate granule cells. We demonstrated that this is due to the aberrant activity-dependent potentiation of the persistent sodium current altering intrinsic firing properties of dentate granule cells.

INTERPRETATION

We propose that this aberrant activity-dependent intrinsic plasticity, which lastingly impairs the information processing of cortical inputs in dentate gyrus, may participate in hippocampal-related cognitive deficits, such as those reported in patients with epilepsy.

Neuropsychological functioning in children with temporal lobe epilepsy and hippocampal atrophy without mesial temporal sclerosis: a distinct clinical entity?

Unilateral hippocampal atrophy (HA) is considered as a precursor of mesial temporal sclerosis (MTS) in some patients with temporal lobe epilepsy. However, in other cases, it has been suggested that HA without MTS may constitute a distinct epileptic entity. Hippocampal atrophy without MTS was defined as HA without T2-weighted hyperintensity, loss of internal architecture, or associated lesion seen on the MRI data. To date, no study has focused on the cognitive pattern of children with epilepsy with HA without MTS. The objectives of the present study were to characterize the cognitive profile of these children and to investigate the presence (or the absence) of material-specific memory deficits in these young patients, as found in patients with MTS. Toward this end, 16 young patients with epilepsy with either left or right HA without MTS completed a set of neuropsychological tests, assessing overall intelligence, verbal memory and nonverbal memory, and some aspects of attention and executive functions. Results showed normal intellectual functioning without specific memory deficits in these patients. Furthermore, comparison between patients with left HA and patients with right HA failed to reveal a material-specific lateralized memory pattern. Instead, attention and executive functions were found to be impaired in most patients. These results suggest that HA may constitute a distinct epileptic entity, and this information may help health-care providers initiate appropriate and timely interventions.

p38 MAP kinase-mediated NMDA receptor-dependent suppression of hippocampal hypersynchronicity in a mouse model of Alzheimer's disease

Hypersynchronicity of neuronal brain circuits is a feature of Alzheimer's disease (AD). Mouse models of AD expressing mutated forms of the amyloid-β precursor protein (APP), a central protein involved in AD pathology, show cortical hypersynchronicity. We studied hippocampal circuitry in APP23 transgenic mice using telemetric electroencephalography (EEG), at the age of onset of memory deficits. APP23 mice display spontaneous hypersynchronicity in the hippocampus including epileptiform spike trains. Furthermore, spectral contributions of hippocampal theta and gamma oscillations are compromised in APP23 mice, compared to non-transgenic controls. Using cross-frequency coupling analysis, we show that hippocampal gamma amplitude modulation by theta phase is markedly impaired in APP23 mice. Hippocampal hypersynchronicity and waveforms are differentially modulated by injection of riluzole and the non-competitive N-methyl-D-aspartate (NMDA) receptor inhibitor MK801, suggesting specific involvement of voltage-gated sodium channels and NMDA receptors in hypersynchronicity thresholds in APP23 mice. Furthermore, APP23 mice show marked activation of p38 mitogen-activated protein (MAP) kinase in hippocampus, and injection of MK801 but not riluzole reduces activation of p38 in the hippocampus. A p38 inhibitor induces hypersynchronicity in APP23 mice to a similar extent as MK801, thus supporting suppression of hypersynchronicity involves NMDA receptors-mediated p38 activity. In summary, we characterize components of hippocampal hypersynchronicity, waveform patterns and cross-frequency coupling in the APP23 mouse model by pharmacological modulation, furthering the understanding of epileptiform brain activity in AD.

Pilocarpine-induced epilepsy is associated with actin cytoskeleton reorganization in the mossy fiber-CA3 synapses

Dramatic structural changes have been demonstrated in the mossy fiber-CA3 synapses in the post status epilepticus (SE) animals, suggesting a potential reorganization of filamentous actin (F-actin) network occurring in the hippocampus. However, until now the long-term effects of SE on the synaptic F-actin have still not been reported. In this study, phalloidin labeling combined with confocal microscopy and protein analyses were adopted to investigate the effects of pilocarpine treatment on the F-actin in the C57BL/6 mice. As compared to the controls, there was ∼ 43% reduction in F-actin density in the post SE mice. Quantitative analysis showed that the labeling density and the puncta number were significantly decreased after pilocarpine treatment (p<0.01, n=5 mice per group, Student's t-test). The puncta of F-actin in the post SE group tended to be highly clustered, while those in the controls were generally distributed evenly. The mean puncta size of F-actin puncta was 0.73±0.19μm(2) (n=1102 puncta from 5 SE mice) in the experimental group, significantly larger than that in the controls (0.51±0.10μm(2), n=1983 puncta from 5 aged-matched control mice, p<0.01, Student's t-test). These observations were well consistent with the alterations of postsynaptic densities in the same region, revealed by immunostaining of PSD95, suggesting the reorganization of F-actin occurred mainly postsynaptically. Our results are indicative of important cytoskeletal changes in the mossy fiber-CA3 synapses after pilocarpine treatment, which may contribute to the excessive excitatory output in the hippocampal trisynaptic circuit.

Magnetoencephalography in presurgical epilepsy diagnosis

Magnetoencephalography (MEG) is a functional modality to register magnetic brain activity with high spatiotemporal resolution. Since distortion of magnetic fields by the skin, skull and cerebrospinal fluids is negligible, the technique offers an almost undistorted view on brain activity. While MEG systems are still expensive and complex, the technique's characteristics offer promising possibilities for the investigation of epilepsy patients, for example, for focus localization and presurgical functional mapping. This review gives an overview of the method and discusses advantages and limitations in the clinical context of presurgical epilepsy diagnosis.

A patient with medication-resistant epilepsy featuring psychosensorial and psychotic symptoms presenting with significant functional improvement on psychotherapeutic treatment: a case report

Background

Partial complex epilepsy with psychosensorial and psychotic symptoms remains a relatively rare condition that can sometimes be mistaken for an axis I psychiatric disorder. There is no specific treatment for this particular type of epilepsy, anti-epileptic medication being the cornerstone of therapeutic intervention with the occasional addition of neuroleptics. Lack of response to anti-epileptic agents is often a sign of poor prognosis and requires risky and sometimes invasive interventions with high morbidity for patients.

Case presentation

We report the case of a 21-year-old right-handed Caucasian man of French-Canadian descent who was living with his mother immediately before being hospitalized in a psychiatric setting for the first time. He seemed obsessed with developing new concepts to reach a more ‘perfect’ existence. He also claimed feeling odd sensations in his mind and in his body that could be linked to some sort of ‘evolutionary’ process resulting from spiritual uplift. He reported non-specific visual hallucinations and what sounded like auditory hallucinations and telepathic powers. The first diagnosis was a possible schizophreniform disorder and our patient was hospitalized. Shortly afterwards, an electroencephalogram showed an important subcortical epileptic activity, compatible with partial complex epilepsy with psychosensorial and psychotic symptoms. Despite a negative response to medication, symptoms proper to this type of epilepsy were substantially alleviated using a psychotherapeutical treatment intended for patients with psychotic disorders, namely integrated psychological therapy (IPT). Significant functional improvement in our patient has been achieved since then.

Conclusions

This case report illustrates that despite a negative response to medication, symptoms proper to this type of epilepsy could be substantially alleviated using psychotherapeutical treatment modalities. To the best of our knowledge, this is the first time such a finding has been reported in the scientific literature. This could open the way for new research themes and therapeutic interventions for such patients.

Association between leisure time, physical activity, and mood disorder levels in individuals with epilepsy

The aim of this study was to investigate the association between physical activity levels (occupational, sports, and leisure time activities), depression, anxiety, and epilepsy. The behavioral outcomes of individuals with epilepsy (E) were also compared with healthy control subjects (C). The sample included 31 individuals with epilepsy (12 with idiopathic generalized epilepsy and 19 with partial epilepsy) and 31 control subjects. Self-rating questionnaires were used to assess mood (State-Trait Anxiety Inventory and Beck Depression Inventory), anxiety, and depression as well as habitual physical activity. Patients with epilepsy were more severely impaired compared to control subjects in both mood questionnaires and presented higher levels of depression (35%), state anxiety (18%), and trait anxiety (12.6%) when compared to the C group. Although physical activity level did not differ significantly between groups, linear regression analyses showed that the physical activity leisure level predicted 31% of depression levels and 26% of anxiety levels in the E group. These data suggest that low levels of physical activity may be considered a risk factor for the development of depression and anxiety and can play an important role in the quality of life of individuals with epilepsy.

Epilepsy in a large cohort of children diagnosed with attention deficit/hyperactivity disorders (ADHD)

PURPOSE

The knowledge about possible relationships between ADHD and epilepsy is largely based on small samples of ADHD patients and on cohorts with epilepsy. There is insufficient information about the clinical characteristics of epilepsy among children diagnosed with ADHD. The aim of this study was to investigate the prevalence and characteristics of epilepsy in a large, unselected cohort of children with ADHD.

METHODS

We conducted a retrospective chart-review of children with ADHD who were evaluated in our clinic between the years 2000 and 2005. We compared age, sex, disorders of psychological development, cognitive level, pharmacological treatment for ADHD, initial response to treatment and ADHD subtype with and without epilepsy. In addition, we compared our data with data from a Norwegian study in a large general pediatric population.

RESULTS

Of 607 children with ADHD (age 6-14 years; 82.4% males); 14 (2.3%) had a history of epilepsy, and 13 of these had active epilepsy. This is a higher occurrence than expected in the general pediatric population (0.5%). The majority of our patients had mild (an easily treated) epilepsy and they were more likely to be seizure free (79%) compared to the patients with epilepsy in general pediatric population. The ADHD patients with and without epilepsy did not differ regarding age, gender, disorders of psychological development, IQ level<85 or ADHD subtype. The patients had been diagnosed with epilepsy on average 1.8 years before the ADHD assessment. All patients with epilepsy were treated with methylphenidate (MPH), and initial response to MPH was achieved in 85.7%.

CONCLUSION

The epilepsy diagnosis preceded the ADHD diagnosis, and was found in a significantly higher rate than would be expected in the general pediatric population. The majority of patients had mild epilepsy and ADHD-Combined Inattentive/Hyperactive-Impulsive Subtype. All cases with epilepsy and ADHD were treated with MPH, with initial response achieved in 86%.

Improving the knowledge of epilepsy and reducing epilepsy-related stigma among children using educational video and educational drama--a comparison of the effectiveness of both interventions

PURPOSE

This study was intended to compare the effectiveness of educational animated video and educational drama in improving the knowledge of epilepsy and reducing epilepsy-related stigma among children aged 9-11 years.

METHOD

The first group of children involved in the study (n(1)=762) watched a video and then completed a questionnaire on epilepsy. The second group (n(2)=400) completed the questionnaire after participating in a drama. Both groups were retested 6 months later by the same questionnaire, which was also completed by a control group (n(3)=180) not subjected to intervention.

RESULTS

Both groups subjected to intervention achieved significantly higher scores (P<0.001) than the control group on knowledge of epilepsy and on attitudes towards children with the disease. Educational video was more effective than drama in improving knowledge of epilepsy. On the other hand, there was no significant difference (P>0.05) between the two kinds of intervention regarding attitudes towards children with this disease.

CONCLUSION

The results suggest that both interventions could be used to reduce epilepsy-related stigma in this age group.

Early deficits in social behavior and cortical rhythms in pilocarpine-induced mouse model of temporal lobe epilepsy

Many patients with epilepsy are afflicted with psychiatric comorbidities including social dysfunction. However, although social deficits have been a major concern in epilepsy treatment, the relationship between social behavioral pathogenesis and the time course of epileptogenesis is not well defined. To address this, we investigated social behavioral alterations and cortical rhythms during two distinct periods in a mouse model of temporal lobe epilepsy (TLE): 1) a seizure-free, latent period after status epilepticus and 2) the subsequent, chronic period characterized by spontaneous recurrent seizures (SRSs). We found that severe social impairments, such as reduced sociability/social novelty preference, social interaction, social learning, and enhanced defensiveness, appeared during the latent period in mice with TLE. The social dysfunctions in the latent-period mice were nearly comparable to those in the chronic-period mice. We also found that both the latent- and chronic-period mice showed similar aberrant neural activities. They showed enhanced delta-band (1-4 Hz) activity and reduced alpha- (8.5-12 Hz) and gamma-band (30-55 Hz) activity during baseline behavior. Interestingly, concomitant increases in alpha- and gamma-band activities during social behavior, which were characteristic in control mice, were not observed in either latent- or chronic-period mice. Our results indicate that social deficits and abnormal neural activities appear at an earlier stage in epileptogenesis regardless of SRS occurrence. These findings may help to understand behavioral pathogenesis in patients with TLE and at-risk patients with initial insults that develop into TLE.

Self-injury in people with intellectual disability and epilepsy: a matched controlled study

We aimed to identify the presence of self-injurious behavior in a sample of 158 people with intellectual disability and epilepsy as compared with a control sample consisting of 195 people with intellectual disability without epilepsy. The Italian Scale for the Assessment of self-injurious behaviors was used to describe self-injurious behavior in both groups. The groups were matched for ID degree: mild/moderate (20 and 20 respectively), severe/profound (45 in both samples) and unknown (4 in both samples). Seventy-four percent of the first sample were diagnosed with symptomatic partial epilepsy. The prevalence of self-injurious behaviors was 44% in the group with intellectual disability and epilepsy and 46.5% in the group with intellectual disability without epilepsy (difference not significant). The areas most affected by self-injurious behaviors in both samples were the hands, the mouth and the head. The most frequent types of self-injurious behaviors were self-biting, self-hitting with hands and with objects. Self-injurious behavior is frequently observed in individuals with epilepsy and intellectual disability. Our study does not suggest that the presence of epilepsy is a risk factor for self-injurious behavior in this patient group.

Behavioral problems in children with epilepsy in rural Kenya

The aims of this study were to record behavioral problems in children with epilepsy (CWE), compare the prevalence with that reported among healthy children without epilepsy, and investigate the risk factors. A child behavioral questionnaire for parents comprising 15 items was administered to the main caregiver of 108 CWE and 108 controls matched for age in Kilifi, Kenya. CWE had a higher mean score for reported behavioral problems than controls (6.9 vs 4.9, t=4.7, P<0.001). CWE with active epilepsy also recorded more behavioral problems than those with inactive epilepsy (8.2 vs 6.2, t=-2.9, P=0.005). A significantly greater proportion of CWE (49% vs 26% of controls) were reported to have behavioral problems. Active epilepsy, cognitive impairment, and focal seizures were the most significant independent covariates of behavioral problems. Behavioral problems in African CWE are common and need to be taken into consideration in planning comprehensive clinical services in this region.

Psychiatric symptomatologies and disorders related to epilepsy and antiepileptic medications

INTRODUCTION

Psychiatric comorbidities (such as depression, anxiety, psychosis, inattention, obsession, personality traits, aggression and suicide) are frequent in patients with epilepsy and have a significant impact on medical management and quality of life.

AREAS COVERED

A literature search was performed in MEDLINE for epidemiological, longitudinal, prospective, double-blind clinical trial studies published between 1990 and 2011 using the following words: epilepsy, antiepileptic drugs (AEDs), behavioral/emotional/psychiatric comorbidities, suicide and aggression. In this review, the author discusses: i) the characterization and prevalence of behavioral disturbances associated with epilepsy, ii) variables correlated with behavioral comorbidities which include: psychosocial-, clinical- and treatment-related variables, iii) the complex mechanisms of behavioral comorbidities associated with epilepsy, which include both psychosocial (functional) and organic; the process of epileptogenesis, neuronal plasticity, abnormalities in hypothalamic-pituitary axis and neurotransmitters and pathways are fundamental determinants, iv) the negative psychotropic effects of AEDs and their mechanisms and v) the suggested biopsychosocial model of management (pharmacological and non-pharmacological).

EXPERT OPINION

The relationship between psychiatric disorders and epilepsy has relevant therapeutic implications which should be directed towards a comprehensive biopsychosocial approach that focuses on the whole person rather than simply on the disease process.

Benign rolandic epileptiform discharges are associated with mood and behavior problems

Children with benign rolandic epilepsy (BRE) experience elevated rates of cognitive, behavioral, and affective problems. Frequent epileptiform spike discharges may impair behavioral functioning. To elucidate this relationship, we evaluated associations between the EEG spike frequency index (SI) and parental ratings of psychosocial adjustment and executive functioning in school-aged children with EEGs typical of BRE. Twenty-one children (6-12 years) participated. Parents completed validated questionnaires at a median of 5 months (range: 1-8) after a routine outpatient EEG. The EEG SI was calculated for wakefulness and sleep. The strength of association between the SI and behavioral variables was evaluated by simple and multivariate correlation. Higher awake and sleep SIs were associated with more symptoms of depression (P<0.001), aggression and conduct problems (P<0.01). Higher sleep SI was associated with executive dysfunction and anxiety (P<0.05). Symptoms of hyperactivity and inattention had no correlation. Increased epileptiform activity in children with BRE may predict higher rates of mood and behavioral problems.

Proteomic profiling of the epileptic dentate gyrus

The development of epilepsy is often associated with marked changes in central nervous system cell structure and function. Along these lines, reactive gliosis and granule cell axonal sprouting within the dentate gyrus of the hippocampus are commonly observed in individuals with temporal lobe epilepsy (TLE). Here we used the pilocarpine model of TLE in mice to screen the proteome and phosphoproteome of the dentate gyrus to identify molecular events that are altered as part of the pathogenic process. Using a two-dimensional gel electrophoresis-based approach, followed by liquid chromatography-tandem mass spectrometry, 24 differentially expressed proteins, including 9 phosphoproteins, were identified. Functionally, these proteins were organized into several classes, including synaptic physiology, cell structure, cell stress, metabolism and energetics. The altered expression of three proteins involved in synaptic physiology, actin, profilin 1 and α-synuclein was validated by secondary methods. Interestingly, marked changes in protein expression were detected in the supragranular cell region, an area where robust mossy fibers sprouting occurs. Together, these data provide new molecular insights into the altered protein profile of the epileptogenic dentate gyrus and point to potential pathophysiologic mechanisms underlying epileptogenesis.

Autism Spectrum Disorder: Correlation between aberrant behaviors, EEG abnormalities and seizures

The relationship between epilepsy, epileptiform discharges, cognitive, language and behavioral symptoms is not clearly understood. Since difficulties with socialization and maladaptive behaviors are found in children with Autism Spectrum Disorder (ASD), we inquired whether epileptiform activity and seizures are associated with adverse behavioral manifestations in this population. We reviewed our EEG database between 1999–2006, and identified 123 children with ASD. EEG abnormalities were found in 39 children (31%). A control group of age and gender matched ASD children with normal EEG’s was obtained. Packets of questionnaires including the Vineland Adaptive Behavior Scale II (VABS), Aberrant Behavior Checklist (ABC) and the Childhood Autism Rating Scale (CARS) were sent by mail. Out of 21 packets received, 11 had normal and 10 had abnormal EEG’s. There were no statistically significant differences in behavior between the two groups. Statistical analysis of discharge location and frequency did not reveal a significant trend. However, children with ASD and seizures had statistically significant lower scores in VABS daily living (P=0.009) and socialization (P=0.007) as compared to those without seizures. ASD children with seizures had higher ABC levels of hyperactivity and irritability. Differences in irritability scores nearly reached statistical significance (P=0.058). There was no significant difference in the degree of CARS autism rating between the groups. Our study did not reveal statistically significant differences in behaviors between ASD children with and without EEG abnormalities. However, ASD children with seizures revealed significantly worse behaviors as compared to counterparts without seizures.

A decision support framework for the discrimination of children with controlled epilepsy based on EEG analysis

BACKGROUND

In this work we consider hidden signs (biomarkers) in ongoing EEG activity expressing epileptic tendency, for otherwise normal brain operation. More specifically, this study considers children with controlled epilepsy where only a few seizures without complications were noted before starting medication and who showed no clinical or electrophysiological signs of brain dysfunction. We compare EEG recordings from controlled epileptic children with age-matched control children under two different operations, an eyes closed rest condition and a mathematical task. The aim of this study is to develop reliable techniques for the extraction of biomarkers from EEG that indicate the presence of minor neurophysiological signs in cases where no clinical or significant EEG abnormalities are observed.

METHODS

We compare two different approaches for localizing activity differences and retrieving relevant information for classifying the two groups. The first approach focuses on power spectrum analysis whereas the second approach analyzes the functional coupling of cortical assemblies using linear synchronization techniques.

RESULTS

Differences could be detected during the control (rest) task, but not on the more demanding mathematical task. The spectral markers provide better diagnostic ability than their synchronization counterparts, even though a combination (or fusion) of both is needed for efficient classification of subjects.

CONCLUSIONS

Based on these differences, the study proposes concrete biomarkers that can be used in a decision support system for clinical validation. Fusion of selected biomarkers in the Theta and Alpha bands resulted in an increase of the classification score up to 80% during the rest condition. No significant discrimination was achieved during the performance of a mathematical subtraction task.