Social cognition and epilepsy surgery

Theory of mind in epilepsy

Epilepsy is characterized by recurrent, chronic, and unprovoked seizures. Epilepsy has a significant negative impact on a patient's quality of life even if seizures are well controlled. In addition to the distress caused by seizures, patients with epilepsy (PwE) may suffer from cognitive impairment with serious social consequences such as poor interpersonal relationships, loss of employment, and reduced social networks. Pathological changes and functional connectivity abnormalities observed in PwE can disrupt the neural network responsible for the theory of mind. Theory of mind is the ability to attribute mental states to other people (intentions, beliefs, and emotions). It is a complex aspect of social cognition and includes cognitive and affective constructs. In recent years, numerous studies have assessed the relationship between social cognition, including the theory of mind, in PwE, and suggested impairment in this domain. Interventions targeting the theory of mind can be potentially helpful in improving the quality of life of PwE.

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.

Hub-connected functional connectivity within social brain network weakens the association with real-life social network in schizophrenia patients

Hubs in the brain network are the regions with high centrality and are crucial in the network communication and information integration. Patients with schizophrenia (SCZ) exhibit wide range of abnormality in the hub regions and their connected functional connectivity (FC) at the whole-brain network level. Study of the hubs in the brain networks supporting complex social behavior (social brain network, SBN) would contribute to understand the social dysfunction in patients with SCZ. Forty-nine patients with SCZ and 27 healthy controls (HC) were recruited to undertake the resting-state magnetic resonance imaging scanning and completed a social network (SN) questionnaire. The resting-state SBN was constructed based on the automatic analysis results from the NeuroSynth. Our results showed that the left temporal lobe was the only hub of SBN, and its connected FCs strength was higher than the remaining FCs in both two groups. SCZ patients showed the lower association between the hub-connected FCs (compared to the FCs not connected to the hub regions) with the real-life SN characteristics. These results were replicated in another independent sample (30 SCZ and 28 HC). These preliminary findings suggested that the hub-connected FCs of SBN in SCZ patients exhibit the abnormality in predicting real-life SN characteristics.

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.

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.

Social brain networks: Resting-state and task-based connectivity in youth with and without epilepsy

Individuals with epilepsy often experience social difficulties and deficits in social cognition. It remains unknown how disruptions to neural networks underlying such skills may contribute to this clinical phenotype. The current study compared the organization of relevant brain circuits-the "mentalizing network" and a salience-related network centered on the amygdala-in youth with and without epilepsy. Functional connectivity between the nodes of these networks was assessed, both at rest and during engagement in a social cognitive task (facial emotion recognition), using functional magnetic resonance imaging. There were no group differences in resting-state connectivity within either neural network. In contrast, youth with epilepsy showed comparatively lower connectivity between the left posterior superior temporal sulcus and the medial prefrontal cortex-but greater connectivity within the left temporal lobe-when viewing faces in the task. These findings suggest that the organization of a mentalizing network underpinning social cognition may be disrupted in youth with epilepsy, though differences in connectivity within this circuit may shift depending on task demands. Our results highlight the importance of considering functional task-based engagement of neural systems in characterizations of network dysfunction in epilepsy.

Reduced structural covariance connectivity of defaut mode network and salience network in MRI-normal focal epilepsy

Neuroimaging studies have found altered functional connectivity of default mode network (DMN) and salience network (SN) in patients with focal epilepsy (FE). However, the structural basis underlying the functional connectivity disturbance in the patients is still unclear. Sixteen MRI-normal FE and 22 healthy controls were included in the current study. The T1 structural image of each participant was obtained. Seed-based structural covariance connectivity was employed to investigate changes of structural covariance connectivity of DMN and SN in FE patients. We further evaluated gray matter volume changes of brain areas showing altered structural connectivity in the patients. We found that patients with FE showed reduced connectivity of posterior cingulate cortex and left medial prefrontal cortex, hippocampus and orbitofrontal cortex, and reduced connectivity of right fronto-insula cortex with left insula, orbitofrontal cortex, opercum part of inferior frontal cortex and right medial prefrontal cortex compared with healthy controls. Moreover, those brain areas showing significant reduced structural covariance connectivity in patients with FE also had a loss of gray matter volume, indicating that reduced structural connectivity of DMN and SN might be associated with gray matter atrophy in the patients. Those results highlight the crucial role of DMN and SN in the pathology of patients with FE, and provided structural basis for the functional disturbance of the two networks in this disease.

Patterns of impaired social cognition in children and adolescents with epilepsy: The borders between different epilepsy phenotypes

Over the past decade, a growing number of studies have shown that children and adolescents with focal and generalized epilepsies have marked impairments in social cognition, including deficits in facial emotion perception (FEP) and Theory of Mind (ToM). At present, it remains unclear whether FEP and ToM impairments are comparable in children with focal and generalized epilepsies or whether distinct syndrome-specific deficits have emerged. This question of whether unique or overlapping social cognitive profiles exist in epilepsy is of interest, given that the revised International League Against Epilepsy (ILAE) classification guidelines propose that seizures arise from a diseased network (i.e., network account), rather than being confined to discrete regions near the site of seizure foci (i.e., localization account). The purpose of this review was as follows: (1) to summarize studies examining FEP and ToM in pediatric patients with epilepsy, (2) to examine epilepsy and psychosocial correlates of these difficulties, and (3) to determine whether patterns of sociocognitive impairment better support a localization or neural network account of epilepsy. Twelve studies were reviewed examining FEP (N = 5) and/or ToM (N = 8). Findings revealed significant FEP and ToM impairments across the studied subgroups with epilepsy, which did not differ between children with generalized and focal (localization-related) epilepsies nor among children with different subtypes of localization-related epilepsy. Similarly, other epilepsy variables (i.e., seizure frequency, side of seizure focus, number of antiepileptic drugs (AEDs) or surgical status) were not related to FEP or ToM, with the exception of younger age at seizure onset and longer duration of epilepsy. Several studies documented a significant relationship between impaired ToM and reduced social competence in pediatric patients with epilepsy, whereas evidence for a relationship between FEP and psychosocial functioning is currently weak. In conclusion, findings suggest that social cognitive impairments represent a shared feature of epilepsy in childhood. The results support a neural network account of epilepsy, in which a shared neural network of dysfunction may be underlying social cognitive deficits in this group. Further research is needed to examine the functional correlates of social cognitive impairments, as well as to evaluate screening tools and treatment methods to identify and address significant social and emotional difficulties in this patient group. This article is part of the Special Issue "Epilepsy and social cognition across the lifespan".

Social cognition, psychiatric comorbidities, and quality of life in adults with epilepsy

Deficits in social cognition are an increasingly recognized complication of epilepsy and contribute to the deficits in social functioning and well-being experienced by patients with epilepsy. Although there has been an increase in studies exploring the measurement and biology of social cognition in patients with epilepsy, there are relatively few examining its clinical implications. Those studies that have been published highlight that social cognitive deficits contribute to impaired quality of life (QoL) in patients with epilepsy, independent of other comorbidities such as depression, anxiety, seizure frequency, and impairment in other cognitive domains. This raises the possibility of novel therapeutic approaches to improving the social well-being of patients with epilepsy.

Should pediatric neurologists play a role in the management of the most common psychiatric comorbidities in children with epilepsy? Practical considerations

Child neurologists should provide initial care for the mental health problems of children and adolescents with epilepsy. Attention deficit hyperactivity disorder (ADHD), autism spectrum disorders are common comorbidities of childhood epilepsy. The psychotropic drugs used to treat mental health disorders can be safely employed in children with seizures. Child neurologists can diagnose common behavioral problems, should be comfortable with first-line agents to treat common psychiatric illnesses, and should recognize when support from psychologists or child and adolescent psychiatrists is needed. This article is part of the Special Issue "Obstacles of Treatment of Psychiatric Comorbidities in Epilepsy".

Social functioning of children after epilepsy surgery: A literature review

This literature review on social functioning of children after epilepsy surgery is based on 24 papers addressing two categories of social functioning: social cognition (n = 4) and general social functioning (n = 20). Overall, studies that compared with healthy peers revealed children who had undergone epilepsy surgery to have more problems in both social cognition and general social functioning. Half of the studies found some improvement in social functioning in the first year(s) after epilepsy surgery, but this pertained to general social functioning, not to social cognition. The persistence of the problems in social cognition after surgery may be related to the critical period of brain maturation, lacking improvement of impairments in related cognitive domains or to a defective underlying brain condition - rather than to the epilepsy. Problems in general social functioning may be explained by the adjustments the children and their families had to make because of the child's drug-resistant epilepsy and difficulties to adjust to the new situation after surgery. The neurological and behavioral explanations are likely to be interrelated in light of the multifaceted and complex nature of social functioning. Epilepsy surgery does not appear to solve the problems in social functioning associated with having had drug-resistant epilepsy. As social functioning is an important aspect of healthy development, it should be assessed comprehensively in order to obtain a knowledge base that allows 1) proper treatment of children with epilepsy (CwE) and 2) counseling patients and families prior to and after epilepsy surgery.

Altered upright face recognition and presence of face inversion effect in temporal lobe epilepsy: An event-related potential study

AIM

Facial recognition can be assessed by examining an event-related potential component, namely the N170. The amplitude of the N170 is larger in response to inverted faces than to upright faces. To examine facial processing in patients with temporal lobe epilepsy (TLE), we investigated the amplitude of the N170, the face inversion effect, and the association between social functioning and face-specific configuration processing.

METHODS

Sixteen patients with TLE and 17 normal controls (NC) participated in this study. Event-related potentials in response to upright or inverted neutral faces and bicycles were recorded. Social functioning was assessed by the socioeconomic status of the participants using the 5-point Hollingshead-Redlich Scale.

RESULTS

Compared with NC, patients with TLE had decreased N170 amplitudes. The inversion effect was observed for face stimuli in both groups; however, no inversion effect was observed for bicycle stimuli. Additionally, in TLE patients, but not in NC, socioeconomic status was significantly correlated with the N170 amplitudes in response to upright faces.

CONCLUSION

In a social context, upright faces are processed as a whole. This process is impaired in TLE. Conversely, inverted faces are processed analytically. This function is normal in TLE. Abnormal face-specific configuration processing may contribute to lower social functioning in TLE.

Theory of Mind impairment in focal versus generalized epilepsy

Theory of Mind (ToM) is a critical component of social cognition, and thus, its impairment may adversely affect social functioning and quality of life. Recent evidence has suggested that it is impaired in epilepsy. What is not clear, however, is whether it is related to particular types of epilepsy or other factors. We undertook the present study to explore ToM in patients with focal versus those with generalized epilepsy, the particular pattern of ToM deficits, and the potential influence of antiepileptic medication load. Our sample included 149 adults: 79 patients with epilepsy (34 with generalized epilepsy and 45 with focal epilepsy) and 70 healthy controls. Theory of Mind tasks included a) comprehension of hinting, b) comprehension of sarcasm and metaphor, c) comprehension of false beliefs and deception, d) recognition of faux pas, and e) a visual ToM task in cartoon form. We found significant ToM impairment in the group with focal epilepsy relative to the performance of both the healthy group and the group with generalized epilepsy on all tasks, with the exception of faux pas, on which the group with generalized epilepsy also performed more poorly than the healthy group. Additionally, early age at seizure onset, but not antiepileptic drug (AED) load, was associated with ToM performance. Our findings suggest that focal temporal and frontal lobe, but not generalized, epilepsies were associated with impaired ToM. This may reflect the neuroanatomical abnormalities in the relevant neuronal networks and may have implications for differential cognitive-behavioral interventions based on epilepsy type.

Impaired social cognition in patients with interictal epileptiform discharges in the frontal lobe

BACKGROUND

Patients with epilepsy frequently experience cognitive impairments, including impairments in social cognition. However, there is a lack of direct examinations of the affective and cognitive aspects of social cognition in such patients. The neural correlates remain to be identified. The present study was designed to examine the degree of impairments in different aspects of social cognition including empathy, emotion recognition, and Theory of Mind (ToM) in patients with epilepsy. In addition, we further explored factors related to the impairments, highlighting the specific importance of the frontal region.

MATERIALS AND METHODS

After 24-hour EEG monitoring, 53 patients with epilepsy were administered a neuropsychological battery of tests for basic intelligence assessment and then were tested with the Interpersonal Reactive Index, the "Yoni" task, the Emotion Recognition Test, the Reading the Mind in the Eyes test, and other neuropsychological tests. The clinical variables potentially affecting the ability to accomplish these tests were taken into account. We divided the patients into those having frontal lobe interictal epileptiform discharges (group with frontal IEDs) and those with seizures originating outside the frontal or temporal lobes (group with extrafrontal IEDs). Sixty healthy individuals served as controls.

RESULTS

The group with frontal IEDs achieved the most severe deficits in emotion recognition, ToM, and cognitive empathy, while affective empathy was intact. Moreover, the performance scores of empathy in the group with frontal IEDs were selectively correlated with their executive function scores, which are believed to be associated with orbitofrontal functioning. In contrast, patients with epilepsies not originating from the frontal or temporal lobes may also be at risk of impairments in social cognition, albeit to a lesser extent.

CONCLUSIONS

The preliminary findings suggest that patients with epilepsy, especially those having frontal lobe interictal epileptiform discharges, have associated general social cognition deficits. At the clinical level, these results are in line with previous findings regarding social cognition and the importance of the prefrontal area in the integration of cognition and affect. At the theoretical level, our findings also provide evidence for the functional independence of cognitive from affective aspects of empathy.

The coordination dynamics of social neuromarkers

Social behavior is a complex integrative function that entails many aspects of the brain’s sensory, cognitive, emotional and movement capacities. Its neural processes are seldom simultaneous but occur according to precise spatiotemporal choreographies, manifested by the coordination of their oscillations within and between brains. Methods with good temporal resolution can help to identify so-called “neuromarkers” of social function and aid in disentangling the dynamical architecture of social brains. In our ongoing research, we have used dual-electroencephalography (EEG) to study neuromarker dynamics during synchronic interactions in which pairs of subjects coordinate behavior spontaneously and intentionally (social coordination) and during diachronic transactions that require subjects to perceive or behave in turn (action observation, delayed imitation). In this paper, after outlining our dynamical approach to the neurophysiological basis of social behavior, we examine commonalities and differences in the neuromarkers that are recruited for both kinds of tasks. We find the neuromarker landscape to be task-specific: synchronic paradigms of social coordination reveal medial mu, alpha and the phi complex as contributing neuromarkers. Diachronic tasks recruit alpha as well, in addition to lateral mu rhythms and the newly discovered nu and kappa rhythms whose functional significance is still unclear. Social coordination, observation, and delayed imitation share commonality of context: in each of our experiments, subjects exchanged information through visual perception and moved in similar ways. Nonetheless, there was little overlap between their neuromarkers, a result that hints strongly of task-specific neural mechanisms for social behavior. The only neuromarker that transcended both synchronic and diachronic social behaviors was the ubiquitous alpha rhythm, which appears to be a key signature of visually-mediated social behaviors. The present paper is both an entry point and a challenge: much work remains to determine the nature and scope of recruitment of other neuromarkers, and to create theoretical models of their within- and between-brain dynamics during social interaction.

Deficit of theory of mind after temporal lobe cerebral infarction

BACKGROUND

Previous studies have indicated that the temporal lobe is involved in theory of mind (ToM). However, little attention has been paid to ToM in patients with cerebral infarction. In this study, we investigated the ability of ToM in patients with temporal lobe cerebral infarction (TLCI) using a variety of tests.

METHODS

In the study, 19 patients with TLCI and 20 healthy controls (HC) were examined using the Recognition of faux pas and the Reading the Mind in the Eyes (RME) tasks, to assess their ability of ToM.

RESULTS

The results of the study indicated that the TLCI group performed significantly worse compared with the HC group as revealed in the total faux pas-related score and in emotion recognition (Mind Reading).

CONCLUSIONS

Our results implied that patients with TLCI had difficulty in ToM. Our data provided new evidence that the temporal lobe may be involved in processing ToM inferences.

Hemispheric asymmetries and prosodic emotion recognition deficits in Parkinson's disease

While Parkinson's disease (PD) has traditionally been described as a movement disorder, there is growing evidence of cognitive and social deficits associated with the disease. However, few studies have looked at multi-modal social cognitive deficits in patients with PD. We studied lateralization of both prosodic and facial emotion recognition (the ability to recognize emotional valence from either tone of voice or from facial expressions) in PD. The Comprehensive Affect Testing System (CATS) is a well-validated test of human emotion processing that has been used to study emotion recognition in several major clinical populations, but never before in PD. We administered an abbreviated version of CATS (CATS-A) to 24 medicated PD participants and 12 age-matched controls. PD participants were divided into two groups, based on side of symptom onset and unilateral motor symptom severity: left-affected (N = 12) or right-affected PD participants (N = 12). CATS-A is a computer-based button press task with eight subtests relevant to prosodic and facial emotion recognition. Left-affected PD participants with inferred predominant right-hemisphere pathology were expected to have difficulty with prosodic emotion recognition since there is evidence that the processing of prosodic information is right-hemisphere dominant. We found that facial emotion recognition was preserved in the PD group, however, left-affected PD participants had specific impairment in prosodic emotion recognition, especially for sadness. Selective deficits in prosodic emotion recognition suggests that (1) hemispheric effects in emotion recognition may contribute to the impairment of emotional communication in a subset of people with PD and (2) the coordination of neural networks needed to decipher temporally complex social cues may be specifically disrupted in PD.

Patient-reported outcome of pediatric epilepsy surgery: social inclusion or exclusion as young adults?

PURPOSE

The purpose of this study was to examine the social relationships and participation in educational, vocational, and community life in young adults who had undergone epilepsy surgery during childhood or adolescence.

METHODS

This was a retrospective, cross-sectional, case-controlled, and multisite design study. Findings were compared between young adults who had undergone epilepsy surgery and were seizure-free in the previous 12 months (n = 38), those who had undergone epilepsy surgery and were not seizure-free (n = 33), and a group of individuals with epilepsy who had not undergone surgery (n = 31).

RESULTS

The surgical seizure-free group had significantly better general social well-being than the other two groups. Specifically, these participants were employed for more months over the past year, were less likely to report that epilepsy had affected their employment, and were more likely to belong to at least one community organization. However, these participants were not any more likely to be involved in a relationship than those in the other two groups. In addition, there were no group differences in the reported number of friends or the frequency of visits with friends, or in what participants described as their principal activity (i.e., student, employed or unemployed).

DISCUSSION

There are a number of benefits to social functioning associated with having had epilepsy surgery and being seizure-free in the past year. Further research is recommended to increase our understanding of the mechanisms involved in the social and personal challenges that these individuals face.

Quality of life in childhood epilepsy with lateralized epileptogenic foci

BACKGROUND

Measuring quality of life (QOL) helps to delineate mechanisms underlying the interaction of disease and psychosocial factors. In adults, epileptic foci in the left temporal lobe led to lower QOL and higher depression and anxiety as compared to the right-sided foci. No study addressed the development of QOL disturbances depending on the lateralization of epileptogenic focus. The objective of our study was to examine QOL in children with lateralized epileptiform discharges.

METHODS

Thirty-one parents of children with epilepsy filled the Health-Related Quality of Life in Childhood Epilepsy Questionnaire (QOLCE). Fifteen children had foci in the left hemisphere and sixteen in the right, as verified with Electroencephalography (EEG) examinations.

RESULTS

We found a significant correlation between foci lateralization and reduced QOL (Spearman's rho = 0.361, p < 0.046). Children with right hemispheric foci exhibited lower overall QOL, particularly in five areas: anxiety, social-activities, stigma, general-health, and quality-of-life.

CONCLUSIONS

We demonstrated for the first time that in children left- and right-hemispheric foci were associated with discordant QOL scores. Unlike in adults, foci in the right hemisphere led to worse emotional and social functioning demonstrating that seizures impact the brain differentially during development.

Association between structural abnormalities and fMRI response in the amygdala in patients with temporal lobe epilepsy

OBJECTIVE

The goal of this study was to investigate whether dysplastic amygdalae show an impaired response as revealed by functional MRI (fMRI).

METHODS

A fearful face fMRI paradigm using video sequences, as we have recently applied, was used in 25 patients with temporal lobe epilepsy (TLE): 24 had mesial TLE (14 right-, nine left-sided, one bilateral); one left lateral neocortical TLE. T1-, T2-weighted and fluid attenuated inversion recovery (FLAIR) MRI sequences were assessed for the detection and categorisation of structural amygdalar abnormalities according to size and MR signal intensity. Of the 25 patients, five patients had probable dysplastic amygdala (pDA): two right- and three left-sided.

RESULTS

A fearful face paradigm led to significant amygdalar activation in all but one patient (p<0.05). In 15 (60%) of the patients amygdalar activation was found contralateral and in four (16%) ipsilateral to the side of seizure onset. Bilateral amygdalar activation was registered in five (20%) patients. In two patients with right-sided and one with left-sided pDA, fMRI activation was observed only in the contralateral amygdala. In two out of three patients with left-sided pDA we found significant ipsilateral amygdalar fMRI-responses.

CONCLUSION

Unilateral pDA does not necessarily affect the amygdalar fMRI BOLD-response.

Psychosocial impairments in children with epilepsy depend on the side of the focus

This article explores the idea that epileptic activity may interfere with psychosocial functions and development in children. In an adult population with epilepsy, left hemispheric seizure focus predicts worse psychosocial functioning. The developmental aspects of these disturbances require further studies. We studied self-report measures of cognitive (locus of control) and emotional (Beck Youth Inventories of Emotional and Social Impairment) functions in 30 children with partial epilepsy (6-15 years) and 60 healthy matched controls. Multivariate statistics revealed significant lateralization effects, with left-sided foci (n=15) leading to more external locus of control. Opposite to adults, the children with right hemispheric foci (n=15) exhibited more emotional impairments (anger, disruptive behavior) than the left hemispheric group. The cognitive and emotional dysfunctions in epilepsy may result from the interaction of focus lateralization and brain development. The cognitive disturbances beginning in childhood may lead to the stronger emotional impairments observed in adults with left hemispheric seizures.

Basic reading skills and dyslexia: three decades following right versus left hemispherectomy for childhood-onset intractable epilepsy

Dyslexia was explored within the framework of three explanations for language functioning following hemispherectomy (i.e., equipotentiality, hemispheric specialization, and crowding hypothesis/hierarchy of specialized functions) and the extent to which these models explain reading performance in S.M. (age 48, right hemispherectomy) and J.H. (age 49, left hemispherectomy). Basic reading performance was evaluated by assessing whole-word and subword reading. Both participants displayed severely impaired reading performance on pseudohomophones (e.g., WUN), signifying poor subword reading. However, J.H. (remaining right hemisphere) also demonstrated impairments in reading exception words (e.g., ONE), suggestive of poor whole-word reading. Thus, although S.M. clearly demonstrated phonological dyslexia and retention of the priority whole-word reading skills, J.H. presented with deficits more characteristic of mixed dyslexia. Taken as a whole, we suggest that some modification of the hierarchy of specialized functioning model and crowding hypothesis is needed, including stipulations about hemispheric specialization, to more accurately accommodate the present data.

Comparison of personality traits in patients with frontal and temporal lobe epilepsies

The current study sought to characterize and compare personality traits of patients with temporal lobe epilepsy (TLE) and frontal lobe epilepsy (FLE). Ninety-seven adults with medically intractable epilepsy (TLE n=58, FLE n=39) completed the Personality Assessment Inventory (PAI) as part of routine preoperative investigations. Not surprisingly, both epilepsy groups endorsed significantly more symptoms across PAI clinical scales than the normative sample, most notably on scales assessing Depression and Somatic Complaints. Direct comparison of personality profiles of people with FLE and TLE revealed that FLE was associated with relative elevations on scales assessing emotional lability and relationship difficulties (i.e., Mania, Borderline Features, Antisocial, Stress, and Nonsupport). Although effect sizes were moderate to large, the clinical significance of these differences was questionable (<1 SD). However, results of a logistic regression suggested that the Borderline Features and Anxiety scales have incremental validity in predicting seizure site (FLE vs TLE) above education and duration of recurrent seizures. These results suggest that patients with FLE may exhibit more behavioral traits associated with frontal dysfunction than patients with TLE.

Social competence of preschool children with epilepsy

The aims of this study were to describe the social competence of 3- to 6-year-old children with epilepsy (n=26) compared with that of age- and gender-matched healthy controls (n=26). Social competence was assessed with the Vineland Social Maturity Scale, Conners' Parent Rating Scales-Revised, and the Child Behavior Checklist. The results indicate that the children with epilepsy, especially with complicated epilepsy, had fewer age-appropriate social skills and more attention and behavior problems than the healthy children, as reported by parents. It is possible that the lack of age-appropriate social skills and the presence of attention problems predispose to behavioral problems. Also, epilepsy-related factors impaired the achievement of social competence. This study shows that the preschool children with complicated, early-onset epilepsy are at increased risk of difficulties in social competence.

Impaired facial emotion recognition in patients with mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS): Side and age at onset matters

To define the determinants of impaired facial emotion recognition (FER) in patients with mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS), we examined 76 patients with unilateral MTLE-HS, 36 prior to antero-mesial temporal lobectomy (AMTL) and 40 after AMTL, and 28 healthy control subjects with a FER test consisting of 60 items (20 each for anger, fear, and happiness). Mean percentages of the accurate responses were calculated for different subgroups: right vs. left MTLE-HS, early (age at onset <6 years) vs. late-onset, and before vs. after AMTL. After controlling for years of education, duration of epilepsy and number of antiepileptic drugs (AEDs) taken, on multivariate analysis, fear recognition was profoundly impaired in early-onset right MTLE-HS patients compared to other MTLE patients and control subjects. Happiness recognition was significantly better in post-AMTL MTLE-HS patients compared to pre-AMTL patients while anger and fear recognition did not differ. We conclude that patients with right MTLE-HS with age at seizure onset <6 years are maximally predisposed to impaired fear recognition. In them, right AMTL does not further worsen FER abilities. Longitudinal studies comparing FER in the same patients before and after AMTL will be required to refine and confirm our cross-sectional observations.

Impaired social cognition 30 years after hemispherectomy for intractable epilepsy: the importance of the right hemisphere in complex social functioning

Clinical research with individuals following hemispherectomy typically quantifies the success of surgical outcomes by focusing primarily on the achievement of seizure control and the preservation of general brain functions, such as movement, sensation, language, and memory. In addition to these outcomes, careful study of individuals following hemispherectomy also has the potential to contribute to our understanding of functional brain asymmetries involving other complex cognitive behaviors. In this study, we report preliminary evidence for the lateralization of social perception. We administered a series of neuropsychological tests that were developed to assess emotional recognition and the formation of social inferences and advanced social cognitive judgments, as they occur in everyday situations, to two adult participants who underwent complete anatomic left- or right-sided hemispherectomy. Our results show that despite a 30-year postsurgical period of recovery and consistent and high levels of family support and social engagement, distinct cognitive profiles are still evident between our right- and left-sided participants. In particular, participant S.M., who underwent an anatomic right hemispherectomy, showed the most severe impairments in identifying negative emotional expressions and conversational exchanges involving lies and sarcasm and in "mentalizing" the intent of others. In contrast, participant J.H., who underwent an anatomic left hemispherectomy was highly skilled interpersonally, despite evident language-related limitations, and showed only mild difficulties when asked to identify emotional expressions involving disgust and anger. These results suggest that the right hemisphere plays a particularly important role in social cognitive functioning and reasoning. Further examination of the extent of social perceptual difficulties prior to and following surgical intervention for epilepsy may guide the development of effective social skills training programs that can improve quality of life beyond seizure control.

Being with virtual others: studying social cognition in temporal lobe epilepsy

Social cognitive neuroscience has highlighted the importance of frontotemporal neurocircuitry for social cognition. Temporal lobe epilepsy (TLE) impacts these brain areas and their functional connections and might therefore specifically affect social perceptual and cognitive skills. In the study described here, an established paradigm was used to evaluate the social cognitive skills of female patients with left TLE. Study participants were shown dynamic animations in which virtual characters either looked at the human observer directly or looked away toward someone else, thus manipulating self-involvement. The virtual characters then exhibited different facial expressions that were either socially relevant or arbitrary. Participants were asked to rate the communicative intentions of the virtual character. Patients' ratings of communicative intent appeared to be linked to their own self-involvement in the interaction, whereas healthy volunteers' ratings of facial expressions were independent of self-involvement. Potential mechanisms for the observed differences are discussed.

Mesial Temporal Lobe Epilepsy Impairs Advanced Social Cognition

PURPOSE

Although memory, language, and executive functions have been extensively studied in patients with mesial temporal lobe epilepsy (MTLE), investigations into advanced social cognitive abilities have been neglected. In the present study, we investigated the ability to detect social faux pas and studied possible mediating clinical and demographic variables in patients with MTLE compared with patients with an epilepsy not originating within the MTLE and healthy controls.

METHODS

The 27 MTLE patients (16 were investigated pre- and 11 postoperatively), 27 patients with an extramesiotemporal epilepsy (except frontal lobe epilepsy), and 12 healthy controls performed a shortened version of the faux-pas test. Additionally, we used standardized tests to measure intelligence. Only patients with intact reading-comprehension abilities were included in the study.

RESULTS

MTLE patients, both pre- and postoperative, performed the faux-pas test significantly worse than patients with extramesiotemporal lobe epilepsy and healthy controls. The latter two groups showed comparable performance. No statistical association was found between the MTLE patients' deficit in recognizing a faux pas and the variables IQ, age, age at seizure onset, and duration of epilepsy.

CONCLUSIONS

We report for the first time that patients with MTLE are specifically impaired in recognizing faux pas, suggesting that MTLE as such is a specific etiology of deficits in higher-order social cognition.