Epilepsy as a Network Disorder (1): What can we learn from other network disorders such as autistic spectrum disorder and mood disorders?

Characteristics of Stroke-related Seizures and their Predictive Factors: A Tertiary Care Center Experience

BACKGROUND AND PURPOSE

Various risk factors have been described in the literature that increase the risk of seizures associated with stroke. This study was aimed to determine the occurrence rate of poststroke seizures (PSSs) and the associated risk factors in Arab population.

MATERIALS AND METHODS

Study included all stroke patients aged >18 years with a minimum follow-up of 24 months following stroke to identify seizure occurrence. Patient's hospital records for all admissions and clinic visits were reviewed. Seizures were classified into early PSS if they occur within 1 week of stroke, and late PSS if they occur after 1 week of stroke.

RESULTS

Out of 594 patients, 380 were males. Seizure occurrence was higher in anterior circulation infarctions (94.8%, P < 0.05), cortical location (80.5%, P < 0.05), large artery atherosclerosis (63.8%, P < 0.05), lower activated partial thromboplastin time (APTT) (P = 0.0007), patients with ischemic heart disease (IHD) (P = 0.01), and those who underwent craniotomy (P = 0.001). Nonhigh-density lipoprotein cholesterol was inversely related to PSS (P = 0.01). Higher stroke severity (89%) and confusion (67%) at the time of presentation were independently related to PSS.

CONCLUSIONS

Eighty-two (13.8%) patients had PSS. Greater stroke severity at presentation with altered sensorium was independent risk factors for the development of PSS. Patients with underlying IHD, lower APTT, and undergoing neurosurgical intervention require vigilant monitoring for PSS.

Evaluating the prevalence and risk factors for depression in patients with temporal lobe epilepsy with hippocampal sclerosis: A cross-sectional multicenter study

BACKGROUND

Epilepsy frequently accompanies Major Depressive Disorder (MDD). Notably, people with temporal lobe epilepsy and hippocampal sclerosis may face an increased susceptibility to MDD, as evidence indicates the involvement of the limbic system in the development of emotional symptoms.

OBJECTIVES

To determine the prevalence and predictors of depression in temporal lobe epilepsy with hippocampal sclerosis (TLE-HS) and compare them to those of other epilepsy types.

METHODS

A sample of 293 epilepsy patients, including 159 non-TLE-HS and 134 TLE-HS, were recruited from three hospitals. Of these, 215 completed a two-section electronic survey. The first section collected demographic and epilepsy data, while the second used the Arabic version of the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E).

RESULTS

Of 215 patients, 104 (48%) had TLE-HS-38 with right TLE-HS (37%), 56 with left TLE-HS (54%), and 10 with bilateral TLE-HS (10%). The prevalence and severity of depression was assessed with an NDDI-E score of 15 or higher identified 35 patients (16%) with MDD. Valproic acid and lamotrigine were associated with higher NDDI-E scores. No such associations were found for levetiracetam or carbamazepine. Polytherapy in TLE-HS showed a significant correlation with daily poor concentration.

CONCLUSION

We explored the differences in depression prevalence between TLE-HS and other epilepsy types and concluded they are minimal but slightly higher in TLE-HS. Predictors of depression such as seizure frequency and disease duration influenced MDD prevalence in TLE-HS. Lamotrigine and valproate were linked to higher NDDI-E scores.

Health related quality of life in a Saudi population of patients with epilepsy

OBJECTIVES

To assess the quality of life for epilepsy patients in Saudi Arabia. Epilepsy, one of the most prevalent chronic neurological conditions in the world, frequently results in a low quality of life.

METHODS

This cross-sectional study analyzed data between September 2020 and September 2021 from 102 adult patients with epilepsy in outpatient clinics department of Epilepsy Program at King Fahad Medical City compared it to 108 healthy controls during the same study period. Sociodemographics and clinical data were gathered using the Arabic version of the Rand 36-Item Short Form Survey (SF-36) questionnaire and the Quality of Life in Epilepsy Inventory (QOLIE-31).

RESULTS

Patients with epilepsy had lower SF-36 scores when compared to the control for role limitation due to physical health, role limitations due to emotional health, and general health. The QOLIE-31 revealed that gender was associated with energy/fatigue (p=0.028), medication effect (p=0.016), and social function (p=0.003); only social functioning showed a significant association (p=0.023) with employment.

CONCLUSION

Quality of life for patients with epilepsy was found to be significantly impacted in Saudi Arabia. Certain factors found in this study differentiate it from data that has already been released. This might be due to Arab differences in family support as well as cultural and religious beliefs.

Neuropsychology of epilepsy surgery and theory-based practice: an opinion review

The present review attempts to discuss how some of the central concepts from the Lurian corpus of theories are relevant to the modern neuropsychology of epilepsy and epilepsy surgery. Through the lenses of the main Lurian concepts (such as the qualitative syndrome analysis), we discuss the barriers to clinical reasoning imposed by quadrant-based views of the brain, or even atheoretical, statistically-based and data-driven approaches. We further advice towards a systemic view inspired by Luria's clinical work and theorizing, given their importance towards our clinical practice, by contrasting it to the modular views when appropriate. Luria provided theory-guided methods of assessment and rehabilitation of higher cortical functions. Although his work did not specifically address epilepsy, his theory and clinical approaches actually apply to the whole neuropathology spectrum and accounting for the whole panorama of neurocognition. This holistic and systemic approach to the brain is consistent with the network approach of the neuroimaging era. As to epilepsy, the logic of cognitive functions organized into complex functional systems, contrary to modular views of the brain, heralds current knowledge of epilepsy as a network disease, as well as the concept of the functional deficit zone.

Attention deficit hyperactivity disorder in patients with seizures: Functional seizures vs. epilepsy

BACKGROUND

We investigated the rates of positive screening for attention deficit-hyperactivity disorder (ADHD) in adults with seizures [i.e., focal epilepsy vs. idiopathic generalized epilepsy (IGE) vs. functional seizures (FS)]. We hypothesized that the rates of positive screening for ADHD are different between these three groups of patients.

METHODS

This was a cross sectional study. Patients, 19 to 55 years of age, with a diagnosis of IGE, focal epilepsy or FS were investigated at the outpatient epilepsy clinic at Shiraz University of Medical Sciences, Shiraz, Iran, from September 2022 until January 2023 and during their follow-up visits. We used the validated Persian version of Adult ADHD Self-Report Scale (ASRS v1.1)15 to investigate and screen for ADHD in these patients.

RESULTS

Forty patients with focal epilepsy, 40 with IGE, and 40 with FS were included. Attention deficit-hyperactivity disorder (ADHD) screening was positive in 35% of patients with FS, in 30% of those with focal epilepsy (compared with FS, p = 0.633), and in 10% of patients with IGE (compared with FS, p = 0.007).

CONCLUSION

Adult patients with functional seizures and those with focal epilepsy are at a high risk of self-reporting experiences that could be characteristic of ADHD. Screening tools [e.g., Adult ADHD Self-Report Scale (ASRS v1.1)] are useful to help clinicians address seizure comorbidities such as ADHD. However, a clinical diagnosis of ADHD should be ascertained in a patient with positive screening.

Inhibitory dysfunction may cause prospective memory impairment in temporal lobe epilepsy (TLE) patients: an event-related potential study

Introduction

Prospective memory (PM) is the ability to remember future intentions, and PM function is closely related to independence in daily life, particularly in patients with temporal lobe epilepsy (TLE). As PM involves various cognitive components of attention, working memory, inhibition and other executive functions, this study investigated how TLE may affect PM components and the underlying neural mechanisms.

Methods

Sixty-four subjects were recruited, including 20 refractory TLE patients, 18 well-controlled TLE patients and 26 age-matched healthy controls. A set of neuropsychological tests was administered to assess specific brain functions. An event-related potential (ERP) task was used to further explore how PM and its components would be differentially affected in the two TLE types.

Results

Our findings revealed that: (1) refractory TLE patients scored lower than the healthy controls in the digit span, Verbal Fluency Test and Symbol Digit Modalities Test; (2) refractory TLE patients exhibited impaired PM performance and reduced prospective positivity amplitudes over the frontal, central and parietal regions in ERP experiments when compared to the healthy controls; and (3) decreased P3 amplitudes in the nogo trials were observed over the frontal-central sites in refractory but not in well-controlled TLE patients.

Discussion

To our knowledge, this is the first ERP study on PM that has specifically identified PM impairment in refractory but not in well-controlled TLE patients. Our finding of double dissociation in PM components suggests that inhibition dysfunction may be the main reason for PM deficit in refractory TLE patients. The present results have clinical implications for neuropsychological rehabilitation in TLE patients.

Bioinformatics and network pharmacology analysis of drug targets and mechanisms related to the comorbidity of epilepsy and migraine

OBJECTIVE

The present study aimed to explore the mechanisms underlying the comorbidity of epilepsy and migraine, identify potential common targets for drug intervention, and provide insight into new avenues for disease prevention and treatment using an integrated bioinformatic and network pharmacology approach.

METHODS

Disease targets in epilepsy and migraine were screened using the DisGeNET database to identify intersecting gene targets. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEEG) enrichment analyses were then performed using the WebGestalt database. Furthermore, the STRING database was used to construct a protein-protein interaction (PPI) network, and Cytoscape software was used to analyze the protein molecular signals at the intersection of epilepsy and migraine. The Drugbank database was used to identify common targets for antiepileptic drugs in epilepsy and migraine to further analyze the disease-gene-target-drug interaction network. Finally, molecular docking simulations were performed to verify the hypothesis that migraine and epilepsy share common diseases and drug targets.

RESULTS

A total of 178 common targets for epilepsy and migraine were identified using the DisGeNET database, and the 24 genes most related to the diseases were screened using the Score_gda gene scoring system. GO enrichment analysis indicated that common targets were mainly enriched in biological processes and molecular functions, including membrane potential regulation, inorganic ion transmembrane transport, axonal signaling, and ion channel activity. KEGG pathway enrichment analysis indicated that the mechanism of action might be related to neuroactive ligand receptors, AGE-RAGE, cAMP, and VEGF signaling pathways. The PPI network construction and analysis results showed that the PPI grid had 23 central nodes and 24 connected edges, with an average node degree of 2.09 and an average clustering coefficient of 0.384. The 10 genes with potentially important roles in epilepsy and migraine were CACNA1A, KCNQ2, KCNA1, SCN1A, PRRT2, SCN8A, KCNQ3, SCN2A, GRIN2A, and GABRG2. Drugbank database results indicated that antiepileptic drugs, including lamotrigine, topiramate, valproic acid, carbamazepine, gabapentin, and perampanel, also had common targets with migraine. The three most important targets exhibited strong binding affinity with drugs in the molecular docking simulations.

CONCLUSION

Our systematic and comprehensive analyses of disease-gene-target-drug interaction networks identified several biological processes and molecular functions common to migraine and epilepsy, most of which were related to neuroactive ligand-receptor interactions. These data provide a new theoretical basis and reference for the clinical treatment of comorbid epilepsy and migraine and may aid in the development of novel pharmacological strategies.

Early cognitive comorbidities before disease onset: A common symptom towards prevention of related brain diseases?

Brain diseases are very heterogeneous; however they also display multiple common risk factors and comorbidities. With a paucity of disease-modifying therapies, prevention became a health priority. Towards prevention, one strategy is to focus on similar symptoms of brain diseases occurring before disease onset. Cognitive deficits are a promising candidate as they occur across brain diseases before disease onset. Based on recent research, this review highlights the similarity of brain diseases and discusses how early cognitive deficits can be exploited to tackle disease prevention. After briefly introducing common risk factors, I review common comorbidities across brain diseases, with a focus on cognitive deficits before disease onset, reporting both experimental and clinical findings. Next, I describe network abnormalities associated with early cognitive deficits and discuss how these abnormalities can be targeted to prevent disease onset. A scenario on brain disease etiology with the idea that early cognitive deficits may constitute a common symptom of brain diseases is proposed.

Pathogenesis of seizures and epilepsy after stroke

Stroke is the most frequent cause of secondary epilepsy in the elderly. The incidence of cerebral stroke is increasing with the extension of life expectancy, and the prevalence of post-stroke epilepsy (PSE) is rising. There are various seizure types after stroke, and the occurrence of epilepsy is closely related to the type and location of stroke. Moreover, the clinical treatment of post-stroke epilepsy is difficult, which increases the risk of disability and death, and affects the prognosis and quality of life of patients. Now seizure and epilepsy after stroke is more and more get the attention of the medical profession, has been more and more researchers have devoted to seizures after stroke and PSE clinical and basic research, and hope to get a scientific and unified guideline, to give timely and effective treatment, but the exact pathophysiologic mechanism has not yet formed a unified conclusion. It has been found that ion channels, neurotransmitters, proliferation of glial cells, genetics and other factors are involved in the occurrence and development of PSE. In this review, we discuss the pathogenesis of early-onset epileptic seizures and late-onset epilepsy after stroke, in order to provide a basis for clinicians to understand the disease, and expect to provide ideas for future exploration.

Forced Normalization Revisited: New Concepts About a Paradoxical Phenomenon

The phenomenon of Forced Normalization (FN) was first described by Landolt in 1953, who described the disappearance of epileptiform discharges in the EEG of patients with epilepsy, concomitant with the development of psychotic symptoms. Later, Tellenbach coined the term “alternative psychosis” referring specifically to the alternation between clinical phenomena. Finally, in 1991, Wolf observed a degenerative process involved in the phenomenon, which he called “paradoxical normalization.” Initially, FN was explained through experimental models in animals and the demonstration of the kindling phenomenon, in its electrical and pharmacological subdivisions. At this stage of research on the epileptic phenomenon, repetitive electrical stimuli applied to susceptible regions of the brain (hippocampus and amygdala) were considered to explain the pathophysiological basis of temporal lobe epileptogenesis. Likewise, through pharmacological manipulation, especially of dopaminergic circuits, psychiatric comorbidities began to find their basic mechanisms. With the development of new imaging techniques (EEG/fMRI), studies in the area started to focus on the functional connectivity (FC) of different brain regions with specific neuronal networks, which govern emotions. Thus, a series of evidence was produced relating the occurrence of epileptic discharges in the limbic system and their consequent coactivation and deactivation of these resting-state networks. However, there are still many controversies regarding the basic mechanisms of network alterations related to emotional control, which will need to be studied with a more homogeneous methodology, in order to try to explain this interesting neuropsychiatric phenomenon with greater accuracy.

Is Preterm Birth a Risk Factor for Subsequent Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder in Children with Febrile Seizure?-A Retrospective Study

Febrile seizure (FS) is the most prevalent childhood seizure; it is significantly related to subsequent epilepsy and has possible links to childhood neurodevelopmental disorders. Separately, premature births are believed to increase the risk of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Therefore, this study investigated whether preterm birth is a risk factor for subsequent epilepsy, ASD, and ADHD in children with FS. We retrospectively collected data for children aged < 5 years with FS from 1 January 2005, to 31 December 2013. We divided these children into two groups-the premature birth group and the full-term group-and compared their incidence rates of epilepsy, ASD and ADHD. The data of 426 patients with history of febrile convulsion were retrospectively collected. The premature birth group (FS+/preterm+) had 108 patients and the full-term group (FS+/preterm-) had 318 patients. The overall epilepsy risk in the FS+/preterm+ group was higher than in the FS+/preterm- group (odds ratio [OR], 2.52; 95% confidence interval [CI], 1.14-5.58; p = 0.02). The overall risk of ADHD in the FS+/preterm+ group was higher than that in the FS+/preterm- group (OR, 6.41; 95% CI, 3.39-12.09; p = 0.0001). In addition, children with FS+/preterm+ had 16.9 times (95% CI, 4.79-59.7; p = 0.0001) higher odds of having ASD compared with those with FS+/preterm-. Preterm birth may be a risk factor for subsequent epilepsy, ASD and ADHD in children with FS.

Disconnecting surgery at alveus and cornu ammonis of hippocampus, amygdala superficialis, and amygdala medial nuclei for epilepsy associated with attention deficit hyperactivity disorder

The neural basis for epilepsy and attention deficit hyperactivity disorder (ADHD) is currently incompletely known. We reported a young girl with both epilepsy and ADHD, who had a calcified lesion in the right basolateral amygdalo-hippocampal region extending to the ventral striatum. The child underwent disconnecting surgery and biopsy of the lesion. Fascinatingly, the child's behavior changed immediately after the surgery from inattentive and impulsive to nearly normal behavior experiencing no more breakthrough seizures since after 3 years of surgery. The Schaltenbrand Wahren Brain Atlas revealed alveus, cornu ammonis, amygdala superficialis, and medium as the disconnected region in this surgery.

Deep Relational Reasoning for the Prediction of Language Impairment and Postoperative Seizure Outcome Using Preoperative DWI Connectome Data of Children With Focal Epilepsy

Prolonged seizures in children with focal epilepsy (FE) may impair language functions and often reoccur after surgical intervention. This study is aimed at developing a novel deep relational reasoning network to investigate whether conventional diffusion-weighted imaging connectome analysis can be improved when predicting expressive and receptive scores of preoperative language impairments and classifying postoperative seizure outcomes (seizure freedom or recurrence) in individual FE children. To deeply reason the dependencies of axonal connections that are sparsely distributed in the whole brain, this study proposes the "dilated CNN + RN", a dilated convolutional neural network (CNN) combined with a relation network (RN). The performance of the dilated CNN + RN was evaluated using whole brain connectome data from 51 FE children. It was found that when compared with other state-of-the-art algorithms, the dilated CNN + RN led to an average improvement of 90.2% and 97.3% in predicting expressive and receptive language scores, and 2.2% and 4% improvement in classifying seizure freedom and seizure recurrence, respectively. These improvements were independent of the prefixed connectome densities. Also, the dilated CNN + RN could provide an explainable artificial intelligence (AI) model by computing gradient-based regression/classification activation maps. This mapping analysis revealed left superior-medial frontal cortex, bilateral hippocampi, and cerebellum as crucial hubs, facilitating important connections that were most predictive of language function and seizure refractoriness after surgery.

The relation of major depression, OCD, personality disorders and affective temperaments with Temporal lobe epilepsy

BACKGROUND

In patients with temporal lobe epilepsy (TLE), studies demonstrate frequent comorbidity with mood disorders, personality disorders (especially obsessive-compulsive disorder) and major depression, but there are conflicting findings. This study aimed to investigate psychiatric comorbidities and affective temperament among TLE patients and to explore the relationships between obsessive compulsive disorder, other personality disorders, major depression and affective temperament in order to clarify the mediator effect of TLE in these relationships.

METHODS

Thirty patients with TLE and 30 healthy volunteers were included. The Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), the Structured Clinical Interview for DSM III-R Axis II Disorders (SCID-II), Hamilton Anxiety (HAM-A) scale, Hamilton Depression (HAM-D) scale, Beck Suicidal Ideation Scale (BSSI) and Yale Brown Obsession Compulsion Scale (YBOCS) were applied and evaluated by a psychiatrist. Additionally, all individuals completed The Temperament Evaluation of Memphis, Pisa, Paris and San Diego (TEMPS-A).

RESULTS

Patients with temporal lobe epilepsy had higher scores in TEMPS-A, HAM-A, HAM-D, YBOCS and BSSI. Major depression, obsessive compulsive disorder and dependent and antisocial personality disorders were prevalent in patients. With respect to affective temperaments, depressive, cyclothymic and anxious temperaments were associated with obsessive compulsive disorder comorbidity; whereas, depressive and anxious temperaments were found to be associated with major depression comorbidity in patients with TLE. Furthermore, cluster A and cluster C personality disorders were associated with affective temperaments in patients with TLE. Affective temperaments had no correlation with illness duration, seizure frequency, depression severity and suicidal thoughts, but obsessions and compulsions. Suicidal thoughts were associated with obsessions and compulsions.

CONCLUSION

Affective temperaments are core personality traits with biological background and they may provide a foundation for psychiatric disorders, especially mood disorders. Considering that TLE originates from abnormalities in brain circuitry, it may form a basis for psychiatric disorders. Therefore, psychiatric evaluation to determine comorbidities may be beneficial to increase the quality of life of patients with TLE.

Global brain network dynamics predict therapeutic responsiveness to cannabidiol treatment for refractory epilepsy

Refractory epilepsy is a chronic brain network disorder characterized by unresponsiveness to multiple (>2) anti-epileptic drugs. Cannabidiol, a non-psychotropic neuroactive substance, is an emerging anti-epileptic treatment that was recently approved by the US Food and Drug Administration for the treatment of refractory epilepsy, especially Lennox Gastaut syndrome and Dravet syndrome. Here, we evaluated associations between global brain network dynamics and related changes and responsiveness to cannabidiol therapy using a combination of electroencephalography phase coherence and graph theoretical analyses. Refractory epilepsy patients with Lennox Gastaut syndrome or Dravet syndrome underwent serial electroencephalography testing prior to and during cannabidiol treatment. Patients showing greater than 70% seizure frequency reduction were classified as treatment responders for the purposes of this study. We calculated inter-electrode electroencephalography phase coherence in delta (1–3 Hz), theta (4–7 Hz), alpha (8–12 Hz) and beta (13–30 Hz) frequency bands. Graph theoretical analysis of brain network dynamics was extracted from phase coherence to evaluate measures of network integration (i.e. characteristic path length, global efficiency and degree) and segregation (i.e. modularity and transitivity). We found that responders, relative to non-responders, showed increased network integration—as indexed by relatively higher global efficiency and lower degree—and increased network segregation—as indexed by relatively higher modularity—exclusively in the beta-frequency band. We also found that larger cannabidiol dosages were associated with increased network integration—as indexed by higher global efficiency with increasing dose—and increased network segregation—as indexed by lower transitivity with increasing dose—in the delta, theta and alpha frequency bands. In summary, we demonstrate novel effects of cannabidiol on brain network dynamics with important implications for the treatment of refractory epilepsy and, possibly, across broader research applications in the future.

Berberine: A Plant-derived Alkaloid with Therapeutic Potential to Combat Alzheimer's disease

Berberine (a protoberberine isoquinoline alkaloid) has shown promising pharmacological activities, including analgesic, anti-inflammatory, anticancer, antidiabetic, anti-hyperlipidemic, cardioprotective, memory enhancement, antidepressant, antioxidant, anti-nociceptive, antimicrobial, anti- HIV and cholesterol-lowering effects. It is used in the treatment of the neurodegenerative disorder. It has strong evidence to serve as a potent phytoconstituent in the treatment of various neurodegenerative disorders such as AD. It limits the extracellular amyloid plaques and intracellular neurofibrillary tangles. It has also lipid-glucose lowering ability, hence can be used as a protective agent in atherosclerosis and AD. However, more detailed investigations along with safety assessment of berberine are warranted to clarify its role in limiting various risk factors and AD-related pathologies. This review highlights the pharmacological basis to control oxidative stress, neuroinflammation and protective effect of berberine in AD, which will benefit to the biological scientists in understanding and exploring the new vistas of berberine in combating Alzheimer's disease.

Major Depressive Disorder Associated With Reduced Cortical Thickness in Women With Temporal Lobe Epilepsy

Background: Major Depressive Disorder (MDD) is highly prevalent in patients with mesial temporal lobe epilepsy (MTLE), especially in women, carrying significant morbidity. This study aimed to investigate the cortical thickness (CT) abnormalities associated with MDD in women with MTLE and hippocampal atrophy (HA). Also, we investigated the impact of MDD upon the volumes of the hippocampus and amygdala in these patients.

Methods: We included 50 women with MTLE and HA (20 left, LMTLE; 30 right, RMTLE), 41 healthy women in the control group, and 15 women with MDD without epilepsy. MTLE patients were subdivided into three groups: MTLE-without-MDD (23 MTLE patients without MDD), MTLE-mild-MDD (nine MTLE patients with mild symptoms of MDD), and MTLE-severe-MDD (18 MTLE patients with moderate to severe symptoms of MDD). The five groups were balanced for age (p = 0.56). All participants had high-resolution 3D T1-weighted images in a 3T scanner. We used FreeSurfer 6.0 for volumetry and CT parcellation. All participants were submitted to a clinical psychological evaluation through the Structured Clinical Interview for DSM-IV (SCID-IV) and completed the Beck Depression Inventory (BDI-II).

Results: We identified a smaller ipsilateral amygdala volume (p = 0.04) in the MTLE-severe-MDD group when compared to the control group. Our results presented a reduced ipsilateral lateral orbitofrontal cortex (p = 0.02) in the MTLE-severe-MDD in comparison to the MTLE-mild-MDD group. We also identified a thinner ipsilateral fusiform gyrus (p < 0.01) in the MTLE-severe-MDD compared to both MTLE-without-MDD and control groups. A reduced CT of the contralateral superior frontal gyrus (p = 0.02) was observed in the MTLE-severe-MDD in comparison to the MTLE-mild-MDD group.

Conclusions: The identification of areas with reduced CT and atrophy of the ipsilateral amygdala in women with MTLE and MDD suggest that the cortical thinning in the network of the paralimbic system is related to the co-occurrence and intensity of depressive symptoms in this group.

Normalization of EEG in depression after antidepressant treatment with sertraline? A preliminary report

BACKGROUND

MDD patients with abnormal EEG patterns seem more likely to be non-responsive to the antidepressants escitalopram and venlafaxine, but not sertraline, than patients without EEG abnormalities. This finding suggests that patients with both MDD and abnormal EEGs may differentially respond to antidepressant treatment. In the current study, we investigated whether depressed patients with an abnormal EEG show a normalization of the EEG related to antidepressant treatment and response and whether such effect is drug specific, and whether having had early life stress (ELS) increases the chance of abnormal activity.

METHODS

Baseline and week 8 EEGs and depression symptoms were extracted from a large multicenter study (iSPOT-D, n = 1008) where depressed patients were randomized to escitalopram, sertraline, or venlafaxine-XR treatment. We calculated Odds Ratios of EEG normalization and depression response in patients with an abnormal EEG at baseline, comparing sertraline versus other antidepressants.

RESULTS

Fifty seven patients with abnormal EEGs were included. EEGs did not normalize significantly more with sertraline compared to other antidepressants (OR = 1.9, p = .280). However, patients with a normalized EEG taking sertraline were 5.2 times more likely to respond than subjects taking other antidepressants (p = .019). ELS was not significantly related to abnormal activity.

LIMITATIONS

Neurophysiological recordings were limited in time (two times 2-minute EEGs) and statistical power (n = 57 abnormal EEGs).

CONCLUSIONS

Response rates in patients with normalized EEG taking sertraline were significantly larger than in subjects treated with escitalopram/venlafaxine. This adds to personalized medicine and suggests a possible drug repurposing for sertraline.

Psychiatric comorbidities go untreated in patients with epilepsy: Ignorance or denial?

Psychiatric comorbidities are common in patients with epilepsy (PWE). Depression and anxiety are the most prevalent of these comorbidities and are associated with worse quality of life. Several screening tools are available to identify and follow up these conditions. However, time constrains in outpatient clinic visits and limited access to mental healthcare professionals discourage clinicians to use them. This paper discusses the advantage and limitations of screening tools and makes a compelling argument for neurologists to take an active role in the diagnosis and treatment of common psychiatric comorbidities in PWE. This article is part of the Special Issue "Obstacles of Treatment of Psychiatric Comorbidities in Epilepsy".

Autism spectrum disorder and attention-deficit/hyperactivity disorder-related symptoms in benign childhood epilepsy with centrotemporal spikes: A prospective case-control study

BACKGROUND

Benign childhood epilepsy with centrotemporal spikes (BECTS), one of the most common idiopathic epilepsy syndromes in children, has been associated with neuropsychological problems.

PURPOSE

The objective of this study was to investigate the frequency of symptoms related to comorbid neurodevelopmental disorders, the autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) in children with typical BECTS, and to identify corresponding risk factors.

METHODS

Children and adolescents with typical BECTS aged 6-16 years were included in the study period from January 1, 2017, to December 31, 2017. Children with atypical presentations of BECTS, other neurological disorders, and preexisting neuropsychiatric disorders were excluded. The ASD and ADHD were assessed by the Social Communication Questionnaire (SCQ) and the Turgay Diagnostic and Statistical Manual of Mental Disorders - 4th Edition - Disruptive Behavior Disorders Rating Scale (T-DSM-IV-S), respectively. Patients' scores were compared with those of healthy subjects. Correlation analyses were performed to evaluate the association between the age at seizure onset, the total number of seizures and the SCQ and T-DSM-IV-S scores.

RESULTS

Fifty-eight children with BECTS and 60 healthy children participated in the study. The total SCQ score, the SCQ reciprocal social interaction score, and the SCQ communication score significantly differed between children with BECTS and the control group (p = 0.001, p < 0.001, p = 0.001, respectively). The total ADHD score was significantly different between patients and controls (p < 0.001). A significant difference was observed between patients and controls in terms of the T-DSM-IV-S hyperactivity-impulsivity score and the T-DSM-IV-S inattention score (p = 0.012, p < 0.001, respectively). The age at seizure onset was significantly correlated with the total SCQ score (p = 0.03). The Spearman's correlation coefficient was 0.352 for the total SCQ score, indicating a positive association between the age at seizure onset and the total SCQ score.

CONCLUSION

Children with typical BECTS may have an increased risk of suffering from symptoms of ASD and ADHD. Children with late onset of seizures may be more likely to develop neuropsychological disturbances regarding ASD and ADHD.

Developments in depression in epilepsy: screening, diagnosis, and treatment

INTRODUCTION

Depression is one of the most frequent comorbidities in epilepsy affecting between 17% and 22% of patients, but it is still underdiagnosed and undertreated. Areas covered: This paper discusses recent advances about screening, diagnosis, and treatment of depression in epilepsy taking into account the heterogeneity of clinical scenarios where depression can occur. Expert opinion: A number of screening instruments are now validated for adults with epilepsy, and their psychometric properties are discussed but the NDDI-E is the most practical and cost-effective. Challenges in diagnosing depression in epilepsy are discussed including reasons for the atypical features of mood disorders in epilepsy. Psychological treatments and/or SSRIs are indicated, but the level of evidence is still low. Even if there is no reason to hypothesise that internationally accepted guidelines of treatment of depression outside epilepsy may not be valid, rigorous studies are needed in order to have proper outcome measures. Epilepsy centers should have well-defined care pathways for depression in order to provide access to mental health support when needed.

Clinical and electroencephalographic correlates of psychiatric features in children with frontal lobe epilepsy

BACKGROUND AND OBJECTIVE

Frontal lobe epilepsy (FLE) is often associated with psychiatric features, although the factors predisposing to the concurrence of these conditions have yet to be determined, especially in younger children. We aimed at defining possible clinical and electroencephalography (EEG) features that may enhance the psychiatric risk in pediatric FLE.

METHOD

We performed a structured psychiatric assessment of 59 children with FLE, using both categorical and dimensional approaches, correlated psychopathology with epilepsy data, and cognitive development.

RESULTS

About 1/3 of patients with FLE displayed intellectual disability (ID), and more than 2/3 displayed psychiatric disorders, including depression, disruptive behaviors, anxiety, and bipolar/psychotic disorders. Psychiatric dimensions such as impulse control problems, attentional deficits, social problems, and aggressive behaviors were frequent features of FLE. Intellectual disability was associated with an earlier onset of psychiatric disorders and more frequent disruptive behavior disorders and aggressiveness. Long-standing epilepsy and bilateral or anterior frontal EEG abnormalities also increased the risk of psychopathology. Finally, right-hemisphere lesions were associated with disruptive behavior disorders, fast EEG rhythms with attention/memory problems, and phases of seizure remission with impulse control problems.

CONCLUSIONS

Clinical and EEG markers of increased psychopathological risk may help in defining consistent at-risk subgroups within FLE and improving early diagnosis, prognosis, and treatment. Categorical and dimensional approaches to psychiatric diagnosis may generate new research hypotheses and support the investigation of the complex pathophysiological bases shared by different neurodevelopmental disturbances.

Gamma oscillations as a biomarker for major depression: an emerging topic

Identifying biomarkers for major depression is of high importance for improving diagnosis and treatment of this common and debilitating neuropsychiatric disorder, as the field seeks to move toward both personalized and more effective treatments. Here we focus on electroencephalography (EEG) or direct scalp voltage recordings as such a biomarker, with an emphasis on gamma and high gamma oscillations (or "rhythms"). In the last several decades, alpha and theta band rhythms have been found to provide information on depressive state as well as recovery, but the gamma band is less well characterized with respect to depression. We summarize some key findings on gamma rhythms (especially their amplitude) as a biomarker or endophenotype for major depression. These studies suggest: (1) under certain conditions gamma rhythms can distinguish subjects with major depression from healthy controls, (2) gamma may distinguish bipolar disorder from unipolar depression, (3) various pharmacological and non-pharmacological treatments that counteract depression also alter gamma, (4) animal models of depression-like behavior show gamma abnormalities, with changes in gamma associated with therapeutic recovery. The most informative approaches in the future may combine profiles of gamma band power across the brain to assess ratios of activity across regions. Overall we have good evidence to suggest that gamma rhythms may provide objective information on major depressive disease status, but we will need further work to better define the precise measures to follow.

IDGenetics: a comprehensive database for genes and mutations of intellectual disability related disorders

Intellectual disability (ID) is one of the most prevalent chronic developmental brain disorders or phenotype of syndromic ID, affecting nearly 1-2% of the general population worldwide. Over recent decades, tremendous effort and high-throughput platforms have been devised to explore the complex heterogeneity, numerous genes and variants have been associated with the ID, especially de novo mutations and copy number variants. An organized resource containing the increasing genetic data is imperative to assist ID research. In this study, the integrative and annotated intellectual disability database has been developed, named 'IDGenetics', which contains known information about ID, including 815 genes and 17102 variants associated with 918 clinical diseases (3001 clinical phenotype) collected from 3822 publications and ID-related databases. Furthermore, in-depth data mining was performed to obtain an understanding of each entry, including functional annotation, gene/disease/phenotype network establishment and overlap analysis focusing on comorbidity. 1478 candidate genes (483 high-confidence and 995 low-confidence) were collected and prioritized by adopting the annotations of 12 functional prediction tools and algorithm. In addition, IDGenetics database provides concise search methods, convenient browsing functions, intuitive graphical displays and constantly updated features. IDGenetics will be a valuable and integrative resource for deciphering the genetic and functional architecture of ID and the improvement of clinical diagnosis, intervention and treatment.

Role of inflammation in epilepsy and neurobehavioral comorbidities: Implication for therapy

Epilepsy is a devastating condition affecting around 70 million people worldwide. Moreover, the quality of life of people with epilepsy (PWE) is worsened by a series of comorbidities. The neurobehavioral comorbidities discussed herein share a reciprocal and complex relationship with epilepsy, which ultimately complicates the treatment process in PWE. Understanding the mechanistic pathway by which these comorbidities are associated with epilepsy might be instrumental in developing therapeutic interventions. Inflammatory cytokine signaling in the brain regulates important brain functions including neurotransmitter metabolism, neuroendocrine function, synaptic plasticity, dopaminergic transmission, the kynurenine pathway, and affects neurogenesis as well as the neural circuitry of moods. In this review, we hypothesize that the complex relationship between epilepsy and its related comorbidities (cognitive impairment, depression, anxiety, autism, and schizophrenia) can be unraveled through the inflammatory mechanism that plays a prominent role in all these individual conditions. An ample amount of evidence is available reporting the role of inflammation in epilepsy and all individual comorbid condition but their complex relationship with epilepsy has not yet been explored through the prospective of inflammatory pathway. Our review suggests that epilepsy and its neurobehavioral comorbidities are associated with elevated levels of several key inflammatory markers. This review also sheds light on the mechanistic association between epilepsy and its neurobehavioral comorbidities. Moreover, we analyzed several anti-inflammatory therapies available for epilepsy and its neurobehavioral comorbidities. We suggest, these anti-inflammatory therapies might be a possible intervention and could be a promising strategy for preventing epileptogenesis and its related neurobehavioral comorbidities.

A Comprehensive Overview on Stress Neurobiology: Basic Concepts and Clinical Implications

Stress is recognized as an important issue in basic and clinical neuroscience research, based upon the founding historical studies by Walter Canon and Hans Selye in the past century, when the concept of stress emerged in a biological and adaptive perspective. A lot of research after that period has expanded the knowledge in the stress field. Since then, it was discovered that the response to stressful stimuli is elaborated and triggered by the, now known, stress system, which integrates a wide diversity of brain structures that, collectively, are able to detect events and interpret them as real or potential threats. However, different types of stressors engage different brain networks, requiring a fine-tuned functional neuroanatomical processing. This integration of information from the stressor itself may result in a rapid activation of the Sympathetic-Adreno-Medullar (SAM) axis and the Hypothalamus-Pituitary-Adrenal (HPA) axis, the two major components involved in the stress response. The complexity of the stress response is not restricted to neuroanatomy or to SAM and HPA axes mediators, but also diverge according to timing and duration of stressor exposure, as well as its short- and/or long-term consequences. The identification of neuronal circuits of stress, as well as their interaction with mediator molecules over time is critical, not only for understanding the physiological stress responses, but also to understand their implications on mental health.

Yield of EEG monitoring in children with developmental disabilities is high

PURPOSE

The purpose of this study was to investigate the yield of a 2-hour electroencephalography (EEG) monitoring (awake and sleep) in children with developmental disabilities and without any clinically apparent seizures.

METHODS

In this retrospective study, I investigated all children below 9 years of age who had developmental disabilities and were referred to Shiraz Comprehensive Epilepsy center for electroencephalographic investigation from June 2017 until January 2018. Exclusion criteria included any past history of neonatal seizures, febrile or afebrile seizures, and parental suspicion for seizures. We systematically obtained a brief clinical history and performed a 2-hour, awake and asleep EEG monitoring for all patients.

RESULTS

Thirty-two patients (23 males and 9 females) met all the inclusion and exclusion criteria; mean age (±standard deviation) was 4.1 (±2.1) years. Nineteen patients (59%) had an abnormal EEG: 15 patients (47%) had epileptiform discharges, and four children had abnormal background activity with no epileptiform discharges.

CONCLUSION

Considering the high diagnostic yield of an awake and asleep EEG monitoring, as it was observed in the current study, this test on a screening basis can be reasonably justified in all children with developmental disabilities.

Bio-electrochemical microelectrode arrays for glutamate and electrophysiology detection in hippocampus of temporal lobe epileptic rats

Temporal Lobe Epilepsy (TLE) is a chronic neurological disorder, characterized by sudden, repeated and transient central nervous system dysfunction. For better understanding of TLE, bio-nanomodified microelectrode arrays (MEA) are designed, for the achievement of high-quality simultaneous detection of glutamate signals (Glu) and multi-channel electrophysiological signals including action potentials (spikes) and local field potentials (LFPs). The MEA was fabricated by Micro-Electro-Mechanical System fabrication technology and all recording sites were modified with platinum black nano-particles, the average impedance decreased by nearly 90 times. Additionally, glutamate oxidase was also modified for the detection of Glu. The average sensitivity of the electrode in Glu solution was 1.999 ± 0.032 × 10^-2pA/μM·μm²(n = 3) and linearity was R = 0.9986, with a good selectivity of 97.82% for glutamate and effective blocking of other interferents. In the in-vivo experiments, the MEA was subjected in hippocampus to electrophysiology and Glu concentration detection. During seizures, the fire rate of spikes increases, and the interspike interval is concentrated within 30 ms. The amplitude of LFPs increases by 3 times and the power increases. The Glu level (4.22 μM, n = 4) was obviously higher than normal rats (2.24 μM, n = 4). The MEA probe provides an advanced tool for the detection of dual-mode signals in the research of neurological diseases.