Impaired Social Cognition in Epilepsy: A Review of What We Have Learnt From Neuroimaging Studies

Investigating the relationship of theory of mind and empathy with neuroimaging, neuropsychological, and neuropsychiatric data in persons with multiple sclerosis

Theory of Mind (ToM) is understanding others' minds. Empathy is an insight into emotions and feelings of others. Persons with multiple sclerosis (pwMS) may experience impairment in ToM and empathy. To investigate ToM, empathy, and their relationship with neuroimaging, neuropsychological, and neuropsychiatric data. 41 pwMS and 41 HC were assessed using RMET for ToM, EQ, BICAMS, HADS. Cortical and subcortical gray matter volumes were calculated with Freesurfer from 3T MRI scans. pwMS showed lower EQ scores (44.82 ± 11.9 vs 51.29 ± 9.18, p = 0.02) and worse RMET performance (22.37 ± 4.09 vs 24,47 ± 2.93, p = 0.011). Anxiety and depression were higher in pwMS. EQ correlated with subcortical (amygdala) and cortical (anterior cingulate) volumes. RMET correlated with cortical volumes (posterior cingulate, lingual). In regression analysis, amygdala volume was the single predictor of empathy performance (p = 0.041). There were no significant correlations between social cognitive tests and general cognition. A weak negative correlation was found between EQ and the level of anxiety (r = -0.342, p = 0.038) The present study indicates that pwMS have impairment on ToM and empathy. The performance of ToM and empathy in MS is linked to the volumes of critical brain areas involved in social cognition.

Navigating Social Waters: Understanding Theory-of-Mind Challenges in Patients with Mesial Temporal Lobe Epilepsy

Background: Temporal lobe epilepsy is a common neurological disease that affects many areas of patients' lives, including social competence. The aim of the study was to assess theory of mind in patients with temporal lobe epilepsy and to investigate the demographic and clinical factors associated with this function. Methods: A total of 65 participants took part in the study, which included 44 patients with epilepsy and 21 demographically matched healthy individuals. The following neuropsychological tests were used to examine theory of mind: the Faux Pas Test, the Hinting Task, the Emotion Comprehension Test, and a cognitive function screen, the Montreal Cognitive Assessment. Results: Patients with epilepsy scored lower on all measures of the theory-of-mind tests. Moreover, in the clinical group, numerous moderate and strong correlations were found between the theory-of-mind tests and education, age at onset of epilepsy, lateralization of epileptic focus, cognitive status, and, to a lesser degree, number of anti-epileptic drugs, frequency of seizures, and age. In contrast, in the control group, significant correlations were found mostly between the theory-of-mind tests and sex, and, to a lesser degree, age. Education and cognitive functioning were not associated. Conclusions: Patients with epilepsy experience difficulties in theory of mind, which may have a negative impact on the quality of their social relationships. The level of theory-of-mind abilities correlates with particular clinical and demographic indicators. Recognizing these issues allows clinicians to implement tailored interventions, potentially improving patients' quality of life.

Cognitive flexibility impairment in temporal lobe epilepsy: The impact of epileptic foci lateralization on executive functions

INTRODUCTION

Temporal Lobe Epilepsy (TLE) has been associated with memory impairments, which are typically linked to hippocampal and mesial temporal cortex lesions. Considering the presence of extensive bidirectional frontotemporal connections, it can be hypothesized that executive dysfunction in TLE is modulated by the lateralization of the epileptic foci.

MATERIAL AND METHODS

A comprehensive neuropsychological executive functions protocol was administered to 63 participants, including 42 individuals with temporal lobe epilepsy (20 with right-TLE and 22 with left-TLE) and 21 healthy controls aged 20-49.

RESULTS

The results indicate that TLE patients exhibit poorer executive performance compared to healthy controls in working memory (F(2,60) = 4.18, p <.01), planning (F(2,60) = 4.71, p <.05), set shifting (F(2,60) = 10.1, p <.001), phonetic verbal fluency (F(2,60) = 11.71, p <.01) and semantic verbal fluency (F(2,60) = 9.61, p <.001. No significant differences were found in cognitive inhibition. Furthermore, right-TLE patients showed lower performance than left-TLE in set shifting (F(1,61) = 6.45, p <.05), while no significant differences were observed in working memory, planning, inhibition, and verbal fluency.

CONCLUSIONS

This research emphasize the importance of considering the lateralization of the temporal lobe focus to achieve a more accurate neuropsychological characterization. The cognitive differences between left and right TLE patients highlight the need for individualized approaches in their treatment and care.

Febrile Seizure Causes Deficit in Social Novelty, Gliosis, and Proinflammatory Cytokine Response in the Hippocampal CA2 Region in Rats

Febrile seizure (FS), which occurs as a response to fever, is the most common seizure that occurs in infants and young children. FS is usually accompanied by diverse neuropsychiatric symptoms, including impaired social behaviors; however, research on neuropsychiatric disorders and hippocampal inflammatory changes following febrile seizure occurrences is very limited. Here, we provide evidence linking FS occurrence with ASD pathogenesis in rats. We developed an FS juvenile rats model and found ASD-like abnormal behaviors including deficits in social novelty, repetitive behaviors, and hyperlocomotion. In addition, FS model juvenile rats showed enhanced levels of gliosis and inflammation in the hippocampal CA2 region and cerebellum. Furthermore, abnormal levels of social and repetitive behaviors persisted in adults FS model rats. These findings suggest that the inflammatory response triggered by febrile seizures in young children could potentially serve as a mediator of social cognitive impairments.

The effect of cannabidiol on seizure features and quality of life in drug-resistant frontal lobe epilepsy patients: a triple-blind controlled trial

Background

Treatment-resistant epileptic seizures are associated with reduced quality of life (QoL). As polypharmacy with routine antiseizure medications has many side effects, novel add-on treatments are necessary. Recent research showed the efficacy of add-on therapy by cannabidiol (CBD) on refractory epilepsy. We attempted to extend data on the efficacy and safety profile of CBD in patients with frontal lobe treatment-resistant epilepsy.

Methods

A total of 27 patients were recruited into two CBD (n = 12) and placebo (n = 15) groups. The CBD group received a highly purified liposomal preparation of the drug in addition to routine antiseizure medications. The placebo group only received antiseizure medications. This experiment followed a triple-blinding protocol. Outcome measures were seizure frequency, the Chalfont seizure severity scale (CSSS), and the quality of life questionnaire score (QOLIE-31) assessed at baseline, 4 weeks, and 8 weeks.

Results

At 4 weeks, results indicated that a higher fraction of patients in the CBD group (66.67%) showed improvement in seizure, compared to the placebo group (20.00%). Before-after comparison revealed that CBD, unlike routine ADEs, was effective in reducing the occurrence of seizures at the study's final timepoint [mean difference 45.58, 95% CI (8.987 to 82.18), p = 0.009]. Seizure severity was not affected by study groups or time intervals (repeated-measures ANOVA p > 0.05). Post-hoc tests found that the QoLI-31 score was improved at 8 weeks compared to baseline [mean diff. -5.031, 95% CI (-9.729 to -0.3328), p = 0.032]. The difference in cases who experienced enhanced QoL was meaningful between the CBD and placebo groups at 8 weeks [RR: 2.160, 95% CI (1.148 to 4.741), p = 0.018] but not at 4 weeks (p = 0.653). A positive finding for QoL improvement was associated with a positive finding for seizure frequency reduction [r = 0.638, 95% CI (0.296 to 0.835), p = 0.001]. Interestingly, limiting the correlation analysis to cases receiving CBD indicated that QoL improvement was not linked with seizure parameters such as severity and frequency (p > 0.05).

Conclusion

The present study suggests the benefit of a purified and highly efficient preparation of CBD for seizure frequency reduction and improvement of QoL in refractory frontal lobe epilepsy. Further study with longer follow-ups and larger sample size is advised.

Clinical trial registration

https://www.irct.ir/trial/56790, identifier: IRCT20210608051515N1.

Exposure to Multicultural Context Affects Neural Response to Out-Group Faces: A Functional Magnetic Resonance Imaging Study

Recent migration and globalization trends have led to the emergence of ethnically, religiously, and linguistically diverse countries. Understanding the unfolding of social dynamics in multicultural contexts becomes a matter of common interest to promote national harmony and social cohesion among groups. The current functional magnetic resonance imaging (fMRI) study aimed to (i) explore the neural signature of the in-group bias in the multicultural context; and (ii) assess the relationship between the brain activity and people's system-justifying ideologies. A sample of 43 (22 females) Chinese Singaporeans (M = 23.36; SD = 1.41) was recruited. All participants completed the Right Wing Authoritarianism Scale and Social Dominance Orientation Scale to assess their system-justifying ideologies. Subsequently, four types of visual stimuli were presented in an fMRI task: Chinese (in-group), Indian (typical out-group), Arabic (non-typical out-group), and Caucasian (non-typical out-group) faces. The right middle occipital gyrus and the right postcentral gyrus showed enhanced activity when participants were exposed to in-group (Chinese) rather than out-group (Arabic, Indian, and Caucasian) faces. Regions having a role in mentalization, empathetic resonance, and social cognition showed enhanced activity to Chinese (in-group) rather than Indian (typical out-group) faces. Similarly, regions typically involved in socioemotional and reward-related processing showed increased activation when participants were shown Chinese (in-group) rather than Arabic (non-typical out-group) faces. The neural activations in the right postcentral gyrus for in-group rather than out-group faces and in the right caudate in response to Chinese rather than Arabic faces were in a significant positive correlation with participants' Right Wing Authoritarianism scores (p < 0.05). Furthermore, the activity in the right middle occipital gyrus for Chinese rather than out-group faces was in a significant negative correlation with participants' Social Dominance Orientation scores (p < 0.05). Results are discussed by considering the typical role played by the activated brain regions in socioemotional processes as well as the role of familiarity to out-group faces.

Human cortical interneurons optimized for grafting specifically integrate, abort seizures, and display prolonged efficacy without over-inhibition

Previously, we demonstrated the efficacy of human pluripotent stem cell (hPSC)-derived GABAergic cortical interneuron (cIN) grafts in ameliorating seizures. However, a safe and reliable clinical translation requires a mechanistic understanding of graft function, as well as the assurance of long-term efficacy and safety. By employing hPSC-derived chemically matured migratory cINs in two models of epilepsy, we demonstrate lasting efficacy in treating seizures and comorbid deficits, as well as safety without uncontrolled growth. Host inhibition does not increase with increasing grafted cIN densities, assuring their safety without the risk of over-inhibition. Furthermore, their closed-loop optogenetic activation aborted seizure activity, revealing mechanisms of graft-mediated seizure control and allowing graft modulation for optimal translation. Monosynaptic tracing shows their extensive and specific synaptic connections with host neurons, resembling developmental connection specificity. These results offer confidence in stem cell-based therapy for epilepsy as a safe and reliable treatment for patients suffering from intractable epilepsy.

Cortico-limbic disruption, material-specificity, and deficits in cognitive-affective theory of mind

The Theory of Mind deficit due to cognitive-affective disintegration is a poorly understood cognitive consequence of cortical and subcortical disruption in right temporal lobe epilepsy. Following Marr's trilevel approach, we used the material-specific processing model to understand the Theory of Mind deficit in drug-resistant epilepsy (N = 30). We examined pre- and post-surgery changes in first-order (somatic-affective, non-verbal component) and second-order Theory of Mind (cognitive-verbal component) in three groups formed using: (i) seizure side (right versus left), (ii) right temporal epilepsy (right temporal lobe epilepsy versus non-right temporal lobe epilepsy), and (iii) right temporal lobe epilepsy with amygdalohippocampectomy (right temporal lobe epilepsy versus left temporal lobe epilepsy amygdalohippocampectomy versus non-amygdalohippocampectomy). We observed a marked deficit in the first-order Theory of Mind in the right temporal lobe amygdalohippocampectomy group; we mapped this deficit to decline in the non-verbal component of Theory of Mind (somatic-affective component). Preliminary results support using a material-specific processing model to understand the Theory of Mind deficits in right temporal lobe epilepsy amygdalohippocampectomy. Malleability of verbal processing in presence of deterioration of non-verbal processing might have clinical relevance for post-surgery recovery in right temporal lobe epilepsy amygdalohippocampectomy. Documenting the material-specific nature of deficits (verbal versus non-verbal) in non-western, linguistically, and socioeconomically diverse country enables us to understand the problem of heterogeneity in post-surgery cognitive consequences in the right amygdalohippocampectomy.

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.

Toward social neuropsychology of epilepsy: a meta-analysis on social cognition in epilepsy phenotypes and a critical narrative review on assessment methods

Background

The aim of this review is to (a) characterize social cognition impairments in the domains of emotion recognition (ER) and theory of mind (ToM) in patients with epilepsy and (b) to review assessment tools with a focus on their validity and usability in clinical practice.

Methods

An electronic search for clinical studies investigating social cognition in epilepsy populations vs healthy control subjects (HC) yielded 53 studies for the meta-analysis and descriptive review.

Results

Results suggest that (1) social cognition is significantly impaired in patients with temporal lobe epilepsy (TLE), frontal lobe epilepsy (FLE) and patients with epilepsy not originating within the temporal or frontal lobes including idiopathic generalized epilepsies (eTLE/eFLE); (2) there is no significant difference between eTLE/eFLE and TLE regarding ER, while TLE and FLE patients perform worse than those with eTLE/eFLE, without significant differences between FLE and TLE regarding ToM ability. A descriptive analysis of the most commonly used assessment tools and stimulus material in this field revealed a lack of ecological validity, usability, and economic viability for everyday clinical practice.

Conclusions

Our meta-analysis shows that patients with epilepsy are at a significantly increased risk of deficits in social cognition. However, the underlying multifactorial mechanisms remain unclear. Future research should therefore specifically address the impairment of processing and methodological problems of testing.

Face-induced gamma oscillations and event-related potentials in patients with epilepsy: an intracranial EEG study

Background

To examine the pathological effect of a mesial temporal seizure onset zone (SOZ) on local and inter-regional response to faces in the amygdala and other structures of the temporal lobe.

Methods

Intracranial EEG data was obtained from the amygdala, hippocampus, fusiform gyrus and parahippocampal gyrus of nine patients with drug-refractory epilepsy during visual stimulation with faces and mosaics. We analyzed event-related potentials (ERP), gamma frequency power, phase-amplitude coupling and phase-slope-index and compared the results between patients with versus without a mesial temporal SOZ.

Results

In the amygdala and fusiform gyrus, faces triggered higher ERP amplitudes compared to mosaics in both patient groups and higher gamma power in patients without a mesial temporal SOZ. In the hippocampus, famous faces triggered higher gamma power for both groups combined but did not affect ERPs in either group. The differentiated ERP response to famous faces in the parahippocampal gyrus was more pronounced in patients without a mesial temporal SOZ. Phase-amplitude coupling and phase-slope-index results yielded bidirectional modulation between amygdala and fusiform gyrus, and predominately unidirectional modulation between parahippocampal gyrus and hippocampus.

Conclusions

A mesial temporal SOZ was associated with an impaired response to faces in the amygdala, fusiform gyrus and parahippocampal gyrus in our patients. Compared to this, the response to faces in the hippocampus was impaired in patients with, as well as without, a mesial temporal SOZ. Our results support existing evidence for face processing deficits in patients with a mesial temporal SOZ and suggest the pathological effect of a mesial temporal SOZ on the amygdala to play a pivotal role in this matter in particular.

Functional patterns of neural activation during vocal emotion recognition in youth with and without refractory epilepsy

Epilepsy has been associated with deficits in the social cognitive ability to decode others' nonverbal cues to infer their emotional intent (emotion recognition). Studies have begun to identify potential neural correlates of these deficits, but have focused primarily on one type of nonverbal cue (facial expressions) to the detriment of other crucial social signals that inform the tenor of social interactions (e.g., tone of voice). Less is known about how individuals with epilepsy process these forms of social stimuli, with a particular gap in knowledge about representation of vocal cues in the developing brain. The current study compared vocal emotion recognition skills and functional patterns of neural activation to emotional voices in youth with and without refractory focal epilepsy. We made novel use of inter-subject pattern analysis to determine brain areas in which activation to emotional voices was predictive of epilepsy status. Results indicated that youth with epilepsy were comparatively less able to infer emotional intent in vocal expressions than their typically developing peers. Activation to vocal emotional expressions in regions of the mentalizing and/or default mode network (e.g., right temporo-parietal junction, right hippocampus, right medial prefrontal cortex, among others) differentiated youth with and without epilepsy. These results are consistent with emerging evidence that pediatric epilepsy is associated with altered function in neural networks subserving social cognitive abilities. Our results contribute to ongoing efforts to understand the neural markers of social cognitive deficits in pediatric epilepsy, in order to better tailor and funnel interventions to this group of youth at risk for poor social outcomes.

Theory of mind and facial emotion recognition in adults with temporal lobe epilepsy: A meta-analysis

BACKGROUND

Mounting studies have investigated impairments in social cognitive domains (including theory of mind [ToM] and facial emotion recognition [FER] in adult patients with temporal lobe epilepsy (TLE). However, to date, inconsistent findings remain.

METHODS

A search of PubMed, Web of Science, and Embase databases was conducted until December 2021. Hedges g effect sizes were computed with a random-effects model. Meta-regressions were used to assess the potential confounding factors of between-study variability in effect sizes.

RESULTS

The meta-analysis included 41 studies, with a combined sample of 1,749 adult patients with TLE and 1,324 healthy controls (HCs). Relative to HCs, adult patients with TLE showed large impairments in ToM (g = -0.92) and cognitive ToM (g = -0.92), followed by medium impairments in affective ToM (g = -0.79) and FER (g = -0.77). Besides, no (statistically) significant differences were observed between the magnitude of social cognition impairment in adult with TLE who underwent and those who did not undergo epilepsy surgery. Meta-regressions exhibited that greater severity of executive functioning was associated with more severe ToM defects, and older age was associated with more severe FER defects.

CONCLUSIONS

Results of this meta-analysis suggest that adult patients with TLE show differential impairments in the core aspects of social cognitive domains (including ToM and FER), which may help in planning individualized treatment with appropriate cognitive and behavioral interventions.

Social cognition in children and adolescents with epilepsy: A meta-analysis

Many studies have investigated impairments in two key domains of social cognition (theory of mind [ToM] and facial emotion recognition [FER]) in children and adolescents with epilepsy. However, inconsistent conclusions were found. Our objective was to characterize social cognition performance of children and adolescents with epilepsy. A literature search was conducted using Web of Science, PubMed, and Embase databases. The article retrieval, screening, quality assessment (Newcastle-Ottawa-Scale), and data extraction were performed independently by two investigators. A random-effects model was used to examine estimates. The meta-analysis included 19 studies, with a combined sample of 623 children and adolescents with epilepsy (mean [SD] age, 12.13 [2.62] years; 46.1% female) and 677 healthy controls [HCs]) (mean [SD] age, 11.48 [2.71] years; 50.7% female). The results revealed that relative to HCs, children and adolescents with epilepsy exhibited deficits in ToM (g = -1.08, 95% CI [-1.38, -0.78], p < 0.001, the number of studies [k] = 13), FER (g = -0.98, 95% CI [-1.33, -0.64], p < 0.001, k = 12), and ToM subcomponents (cognitive ToM: g = -1.04, 95% CI [-1.35, -0.72], p < 0.001, k = 12] and affective ToM: g = -0.73, 95% CI [-1.12, -0.34], p < 0.001, k = 8). In addition, there were no statistically significant differences in social cognition deficits between children and adolescents with focal epilepsy and generalized epilepsy. Meta-regressions confirmed the robustness of the results. These quantitative results further deepen our understanding of the two core domains of social cognition in children and adolescents with epilepsy and may assist in the development of cognitive interventions for this patient population. Systematic review registration: https://inplasy.com/inplasy-2022-3-0011/, identifier INPLASY202230011.

Affective Empathy, Theory of Mind and Social Functioning in Patients With Focal Epilepsy

OBJECTIVE

Social cognition comprises basic and more complex functions, such as theory of mind (ToM) and affective empathy. Although everyday social interactions may be impaired if such higher-order social cognitive functions are compromised, associations between social functioning and social cognition in people with focal epilepsy (PWFE) are still poorly understood. We used a novel, naturalistic approach to investigate ToM in PWFE by applying the Movie for the Assessment of Social Cognition (MASC). Furthermore, we studied affective empathy, the relationship between social cognitive parameters and measures of social functioning, as well as between epilepsy focus and ToM.

METHODS

Thirty patients with either temporal (TLE) or frontal lobe epilepsy (FLE) were compared to 29 healthy control subjects (HC). In addition to the MASC, we applied questionnaire measures assessing empathy and everyday social functioning.

RESULTS

PWFE, especially with FLE, performed significantly worse than HC on the MASC. Perceived social integration and social activities, but not affective empathy, were reduced in PWFE. Regression analyses revealed associations between perceived social integration, clinical group status, affective empathy and ToM.

CONCLUSION

PWFE displayed ToM deficits during a naturalistic task, whereas affective empathy was unimpaired. FLE may be associated with especially compromised ToM performance. Social cognition and social functioning appear to be interrelated in PWFE, whose self-perceived levels of social integration and social activities are lower than those of HC. More research into the association between social cognition and social functioning in PWFE is needed, in order to develop tailored intervention programs for these patients.

The effect of facial expression intensity on emotion recognition and psychosocial performance in patients with frontal or temporal lobe epilepsy

PURPOSE

No studies have examined the relationship between the intensity of facial emotion expression and theory of mind (ToM) ability in people with epilepsy. This study aimed to explore facial emotion recognition in a group of patients with frontal (FLE) or temporal lobe epilepsy (TLE) and its relationship with the intensities of perceived facial emotion expressions, ToM, and social functioning.

METHODS

Twenty-six patients with FLE or TLE and 30 matched controls were included in the study. All participants completed the facial emotion recognition test, Faux Pas Recognition (FPR) test measuring advanced ToM, Symptom Checklist-90-Revised, Social and Occupational Functioning Scale for Epilepsy (SOFSE), and background neuropsychological tests.

RESULTS

The patient group was significantly worse than the control group in recognizing facial expressions of negative emotions, particularly for medium-intensity facial expression of fear. There was no significant difference between the groups in recognizing high-intensity fear facial expressions. The scores of FPR (overall and affective ToMs) in the patient group were significantly lower than those in the control group. Additionally, the facial emotion recognition was significantly associated with the total score of FPR, and the FPR total score remarkably correlated with the Communication subscale score of the SOFSE.

CONCLUSIONS

Patients with FLE or TLE had impaired ability to recognize medium-intensity facial expressions of fear. Moreover, patients' ToM deficit significantly correlated not only with their emotion recognition problem but also with their social-communicative competence. Nevertheless, we also found that increasing the intensity of expression can improve the accuracy of emotion recognition in patients with epilepsy. These findings may provide considerations for further longitudinal studies and interventions on the social difficulties of people with epilepsy.

Theory of Mind and Empathy in Adults With Epilepsy: A Meta-Analysis

Mounting evidence suggests that social cognitive abilities [including theory of mind (ToM) and empathy] are impaired in adult patients with epilepsy. Although the deficits in overall ToM in epilepsy have been documented well, the effects of epilepsy on empathic ability and specific subcomponents of ToM remain unclear. The primary aim of this study was to provide the first meta-analytic integration of ToM and empathy in adult patients with epilepsy, and to decompose these constructs to clearly differentiate their distinct (cognitive ToM and affective empathy) and overlapping (affective ToM/cognitive empathy) components. This meta-analysis included 28 studies. Adult patients with temporal lobe epilepsy (TLE) and frontal lobe epilepsy (FLE) showed impairments in cognitive ToM and affective ToM/cognitive empathy compared to the healthy controls (HCs); no group differences were identified for affective empathy. Besides, cognitive ToM was impaired in adult patients with idiopathic generalized epilepsy (IGE) and focal seizures (caused by epileptogenic foci) outside the temporal and frontal lobes (extra-TLE/FLE) and no group differences were evident for affective ToM/cognitive empathy compared to the HCs. Moreover, relative to the HCs, no group differences were identified for affective empathy in adult patients with IGE. Additionally, no (statistically) significant difference was observed between the magnitude of ToM/empathy impairment in adult patients who underwent and those who did not undergo epilepsy surgery. These quantitative findings suggest differential impairment of the core aspects of social cognitive processing in adult patients with epilepsy, which may contribute to the development of structured cognitive interventions (i.e., social cognitive training) for adult patients with epilepsy.

Identification and Validation of a Dysregulated miRNA-Associated mRNA Network in Temporal Lobe Epilepsy

Objectives

This study is aimed at exploring the relationships between miRNAs and mRNAs and to characterize their biological functions in temporal lobe epilepsy (TLE).

Methods

Novel clinical significant miRNAs and target genes and their potential underlying mechanisms have been discovered and explored by mining miRNAs and mRNA expression data of TLE patients using various bioinformatics methods. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to validate the bioinformatic analysis results.

Results

A total of 6 dysregulated miRNAs and 442 differentially expressed genes (DEGs) related to TLE were obtained from GEO database (GSE114701 and GSE127871 datasets). A protein-protein interaction (PPI) network containing the 442 DEGs was established. mRNA response elements from the 6 dysregulated miRNAs were predicted using the miRDB and TargetScan bioinformatic tools. By merging the identified targets of the dysregulated miRNAs and the 247 downregulated DEGs, a miRNA-mRNA network was constructed revealing the interaction of miR-484 with eight mRNAs (ABLIM2, CEP170B, CTD-3193O13.9, EFNA5, GAP43, PRKCB, FXYD7, and NCAN). A weighted correlation network analysis (WGCNA) based on the eight genes was established and demonstrated that these mRNAs, except FXYD7 and NCAN, were hub genes in the network. Gene Oncology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that the six hub genes were mainly involved in cellular-related biological functions and the neurotransmitter synapse pathway. The differences in expression levels of the miR-484 and the three hub genes (CTD-3193O13.9, EFNA5, and PRKCB) observed experimentally in TLE patients compared to those of healthy controls were consistent with the WGCNA prediction.

Conclusion

Our study suggests that understanding the miRNA-mRNA interactions will provide insights into the epilepsy pathogenesis. In addition, our results indicate that miR-484 may be a promising novel biomarker for TLE.

Emotion recognition and theory of mind after temporal lobe epilepsy surgery: A systematic review

In order to navigate in our complex social world successfully, it is crucial to maintain and practice cognitive skills that are dedicated to adaptive social functioning. Emerging evidence suggests that besides deficits in declarative memory, executive functions, and language, impairments in social cognition (SC, e.g., emotion recognition, theory of mind) are also present in temporal lobe epilepsy (TLE). The organic and psycho-social consequences of epilepsy surgery might have additional implications regarding this deficit. Here we qualitatively synthesize longitudinal and cross-sectional findings on SC after TLE surgery. A literature search using PubMed and Scopus identified 275 potential articles. Studies were eligible if they (1) included patients with a diagnosis of TLE, (2) included a healthy comparison group, (3) reported original research, (4) were published in peer-reviewed journals and in English language, (5) reported the intervention of epilepsy surgery. Articles that (1) were case studies, (2) did not focus on SC abilities, (3) used interviews or self-report questionnaires to examine SC functions were excluded. A total of 16 original studies assessing emotion recognition (ER) and/or theory of mind (ToM) matched our criteria. The literature suggests that neither ER nor ToM abilities change after surgery: post-surgery patients show similar impairment patterns to pre-surgery patients. Nevertheless, individual improvement or decline could be masked by group comparisons and results should be considered in light of methodological heterogeneity among studies.

Temporal lobe epilepsy alters neural responses to human and avatar facial expressions in the face perception network

BACKGROUND AND OBJECTIVE

Although avatars are now widely used in advertisement, entertainment, and business today, no study has investigated whether brain lesions in neurological patients interfere with brain activation in response to dynamic avatar facial expressions. The aim of our event-related fMRI study was to compare brain activation differences in people with epilepsy and controls during the processing of fearful and neutral dynamic expressions displayed by human or avatar faces.

METHODS

Using functional magnetic resonance imaging (fMRI), we examined brain responses to dynamic facial expressions of trained actors and their avatar look-alikes in 16 people with temporal lobe epilepsy (TLE) and 26 controls. The actors' fearful and neutral expressions were recorded on video and conveyed onto their avatar look-alikes by face tracking.

RESULTS

Our fMRI results show that people with TLE exhibited reduced response differences between fearful and neutral expressions displayed by humans in the right amygdala and the left superior temporal sulcus (STS). Further, TLE was associated with reduced response differences between human and avatar fearful expressions in the dorsal pathway of the face perception network (STS and inferior frontal gyrus) as well as in the medial prefrontal cortex.

CONCLUSIONS

Taken together, these findings suggest that brain responses to dynamic facial expressions are altered in people with TLE compared to neurologically healthy individuals-regardless of whether the face is human or computer-generated. In TLE, areas sensitive to dynamic facial features and associated with processes relating to the self and others are particularly affected when processing dynamic human and avatar expressions. Our findings highlight that the impact of TLE on facial emotion processing must be extended to artificial faces and should be considered when applying dynamic avatars in the context of neurological conditions.

Social Cognition in Neurodevelopmental Disorders and Epilepsy

Introduction: The purpose of our study was to perform a comparative analysis of social cognition in children and adolescents with epilepsy, autism spectrum disorder (ASD), specific learning disorder (SLD) and in typical development (TD) controls. The secondary aim was to relate social cognition to some clinical and demographic characteristics.

Methods: Our work is a transversal observational study. The recruits were 179 children and adolescents aged between 6 and 18 years diagnosed with epilepsy, ASD, or SLD and 32 subjects with TD. All the participants underwent neuropsychological assessment of Emotion Recognition (ER) and Theory of Mind (ToM) skills.

Results: All three clinical groups performed significantly worse than controls in ER and ToM. The ASD group achieved significantly lower performance than the other groups; however, the scores of SLD and epilepsy groups were comparable. The ER performances are related to non-verbal intelligence only in the group with epilepsy.

Conclusion: Children and adolescents with focal epilepsy, SLD, or ASD may present a deficit of varying extent in emotion recognition and ToM, compared with TD peers. These difficulties are more pronounced in individuals with ASD, but impairment worthy of clinical attention also emerges in individuals with SLD and epilepsy.

Mechanisms of cognitive impairment in temporal lobe epilepsy: A systematic review of resting-state functional connectivity studies

Temporal lobe epilepsy is the most common form of focal epilepsy and related cognitive dysfunction impacts significantly on quality of life in patients. Identifying the mechanisms of such impairment would assist in the management and treatment of patients. The study of perturbations in resting-state networks could shed light on this subject. The aim of this systematic review was to synthesize findings on the relationship between aberrant resting-state functional connectivity and cognitive performance in patients with TLE. Literature searches were conducted on Scopus and PubMed electronic databases and 17 relevant articles were extracted, all of which studied the association between resting-state functional connectivity (RSFC) and cognition in adults with TLE. Study findings were synthesized according to methods used to analyze resting-state data, cognitive domains tested, and neuropsychology tasks administered. Results show that increased RSFC in the primary epileptogenic hippocampus, and reduced intra-hemispheric RSFC, are associated with weaker memory performance. In left TLE, memory impairment may be compensated for by bilateral hippocampal connectivity, which is also predictive of better postoperative memory outcomes. In right TLE, memory loss may be compensated for by increased connectivity between the contralateral hippocampus and inferior frontal gyrus. There is also tentative evidence that working memory dysfunction is related to reduced RSFC between the medial frontal-insular parietal network and the medial temporal network, executive dysfunction is related to reduced RSFC between frontal and parietal lobes, and between the frontal lobe and subcortical regions and that language dysfunction is related to reduced RSFC within the left fronto-temporal language network. Multicenter studies could refute or support these findings by enrolling large samples of patients and employing multivariate regression analysis to control for the effects of anatomical disruption, interictal discharges, seizure frequency, medication, and mood. Systematic review registration: PROSPERO: 191323.

Increased Endocannabinoid Signaling Reduces Social Motivation in Intact Rats and Does Not Affect Animals Submitted to Early-Life Seizures

The early life status epilepticus (SE) causes high anxiety and chronic socialization abnormalities, revealed by a low preference for social novelty and deficit in social discrimination. This study investigated the involvement of the endocannabinoid system on the sociability in this model, due to its role in social motivation regulation. Male Wistar rats at postnatal day 9 were subjected to pilocarpine-induced neonatal SE and controls received saline. From P60 the groups received vehicle or JZL195 2 h before each behavioral test to increase endocannabinoids availability. In the sociability test, animals subjected to neonatal SE exhibited impaired sociability, characterized by social discrimination deficit, which was unaffected by the JZL195 treatment. In contrast, JZL195-treated control rats showed low sociability and impaired social discrimination. The negative impact of JZL195 over the sociability in control rats and the lack of effect in animals subjected to neonatal SE was confirmed in the social memory paradigm. In this paradigm, as expected for vehicle-treated control rats, the investigation toward the same social stimulus decreased with the sequential exposition and increased toward a novel stimulus. In animals subjected to neonatal SE, regardless of the treatment, as well as in JZL195-treated control rats, the investigation toward the same social stimulus was significantly reduced with no improvement toward a novel stimulus. Concerning the locomotion, the JZL195 increased it only in control rats. After behavioral tests, brain tissues of untreated animals were used for CB1 receptor quantification by Elisa and for gene expression by RT-PCR: no difference between control and experimental animals was noticed. The results reinforce the evidence that the early SE causes chronic socialization abnormalities, revealed by the low social interest for novelty and impaired social discrimination. The dual FAAH/MAGL inhibitor (JZL195) administration before the social encounter impaired the social interaction in intact rats with no effect in animals subjected to early-life seizures.

Social cognition and executive functions in children and adolescents with focal epilepsy

OBJECTIVES

Deficits in facial emotion recognition and Theory of Mind are frequent in patients with epilepsy. Although this evidence, studies on pediatric age are few and the relation between these abilities and other cognitive domain remains to be better elucidated. The purpose of our study is to evaluate facial emotion recognition and Theory of Mind in children and adolescents with focal epilepsy, and correlate them with intelligence and executive functions.

MATERIALS AND METHODS

Our work is a cross-sectional observational study. Sixty-two children and adolescents aged between 7-16 years diagnosed by focal epilepsy and 32 sex/age-matched controls were recruited. All participants were administered a standardized battery tests to assess social cognition (NEPSY-II), executive functions (EpiTrack Junior) and cognitive non-verbal level (Raven Progressive Matrices).

RESULTS

Emotion recognition mean score was significantly lower in the epilepsy group than in the controls to Student's t-test (p<0.05). Epilepsy group showed an impairment in happiness, sadness, anger and fear recognition, compared to controls (p<0.05). Theory of Mind mean score was also significantly lower in epilepsy group than controls (p<0.05). Deficits in emotion recognition seemed to be related to low age at onset of epilepsy, long duration of disease, low executive functions and low non-verbal intelligence. Deficits in Theory of Mind seemed to be related to a high seizure frequency.

CONCLUSIONS

Our results suggest that children and adolescents with focal epilepsy had deficit in facial emotion recognition and Theory of Mind, compared to their peer. Both these difficulties seem to be related to some features of epilepsy itself. Our results also suggest that deficits in facial emotion recognition are potentially related to difficulties in executive functions and non-verbal intelligence. More studies are needed to confirm these hypotheses.

Microstates-based resting frontal alpha asymmetry approach for understanding affect and approach/withdrawal behavior

The role of resting frontal alpha-asymmetry in explaining neural-mechanisms of affect and approach/withdrawal behavior is still debatable. The present study explores the ability of the quasi-stable resting EEG asymmetry information and the associated neurovascular synchronization/desynchronization in bringing more insight into the understanding of neural-mechanisms of affect and approach/withdrawal behavior. For this purpose, a novel frontal alpha-asymmetry based on microstates, that assess quasi-stable EEG scalp topography information, is proposed and compared against standard frontal-asymmetry. Both proposed and standard frontal alpha-asymmetries were estimated from thirty-nine healthy volunteers resting-EEG simultaneously acquired with resting-fMRI. Further, neurovascular mechanisms of these asymmetry measures were estimated through EEG-informed fMRI. Subsequently, the Hemodynamic Lateralization Index (HLI) of the neural-underpinnings of both asymmetry measures was assessed. Finally, the robust correlation of both asymmetry-measures and their HLI’s with PANAS, BIS/BAS was carried out. The standard resting frontal-asymmetry and its HLI yielded no significant correlation with any psychological-measures. However, the microstate resting frontal-asymmetry correlated significantly with negative affect and its neural underpinning’s HLI significantly correlated with Positive/Negative affect and BIS/BAS measures. Finally, alpha-BOLD desynchronization was observed in neural-underpinning whose HLI correlated significantly with negative affect and BIS. Hence, the proposed resting microstate-frontal asymmetry better assesses the neural-mechanisms of affect, approach/withdrawal behavior.

Impaired Cognitive Abilities in Siblings of Patients with Temporal Lobe Epilepsy

PURPOSE

Patients with temporal lobe epilepsy (TLE) are at high risk of cognitive impairment. In addition to persistent seizures and antiepileptic drugs (AEDs), genetic factors also play an important role in the progression of cognitive deficits in TLE patients. Defining a cognitive endophenotype for TLE can provide information on the risk of cognitive impairment in patients. This study investigated the cognitive endophenotype of TLE by comparing neuropsychological function between patients with TLE, their unaffected siblings, and healthy control subjects.

PATIENTS AND METHODS

A total of 46 patients with TLE, 26 siblings, and 33 control subjects were recruited. Cognitive function (ie, general cognition, short- and long-term memory, attention, visuospatial and executive functions, and working memory) was assessed with a battery of neuropsychological tests. Differences between groups were evaluated by analysis of covariance, with age and years of education as covariates. The Kruskal-Wallis test was used to evaluate data that did not satisfy the homogeneity of variance assumption. Pairwise comparisons were adjusted by Bonferroni correction, with a significance threshold of P<0.05.

RESULTS

Patients with TLE showed deficits in the information test (P<0.001), arithmetic test (P=0.003), digit symbol substitution test (P=0.001), block design test (BDT; P=0.005), and backward digit span test (P=0.001) and took a longer time to complete the Hayling test Part A (P=0.011) compared to controls. Left TLE patients tended to have worse executive function test scores than right TLE patients. The siblings of TLE patients showed deficits in the BDT (P=0.006, Bonferroni-corrected) relative to controls.

CONCLUSION

Patients with TLE exhibit cognitive impairment. Executive function is worse in patients with left TLE than in those with right TLE. Siblings show impaired visuospatial function relative to controls. Thus, cognitive deficits in TLE patients have a genetic component and are independent of seizures or AED use.