Delineating behavioral and cognitive phenotypes in juvenile myoclonic epilepsy: Are we missing the forest for the trees?

The landscape of drug resistant absence seizures in adolescents and adults: Pathophysiology, electroclinical spectrum and treatment options

The persistence of typical absence seizures (AS) in adolescence and adulthood may reduce the quality of life of patients with genetic generalized epilepsies (GGEs). The prevalence of drug resistant AS is probably underestimated in this patient population, and treatment options are relatively scarce. Similarly, atypical absence seizures in developmental and epileptic encephalopathies (DEEs) may be unrecognized, and often persist into adulthood despite improvement of more severe seizures. These two seemingly distant conditions, represented by typical AS in GGE and atypical AS in DEE, share at least partially overlapping pathophysiological and genetic mechanisms, which may be the target of drug and neurostimulation therapies. In addition, some patients with drug-resistant typical AS may present electroclinical features that lie in between the two extremes represented by these generalized forms of epilepsy.

Neuromorphometric associations with mood, cognition, and self-reported exercise levels in epilepsy and healthy individuals

Regular physical activity may promote beneficial neuroplasticity, e.g., increased hippocampus volume. However, it is unclear whether self-reported physical exercise in leisure (PEL) levels are associated with the brain structure features demonstrated by exercise interventions. This pilot study investigated the relationship between PEL, mood, cognition, and neuromorphometry in patients with idiopathic generalized epilepsy (IGEs) compared to healthy controls (HCs). Seventeen IGEs and 19 age- and sex-matched HCs underwent magnetic resonance imaging (MRI) at 3T. The Baecke Questionnaire of Habitual Physical Activity, Profile of Mood States, and Montreal Cognitive Assessment (MoCA) assessed PEL, mood, and cognition, respectively. Structural MRI data were analyzed by voxel- and surface-based morphometry. IGEs had significantly lower PEL (p < 0.001), poorer mood (p = 0.029), and lower MoCA scores (p = 0.027) than HCs. These group differences were associated with reduced volume, decreased gyrification, and altered surface topology (IGEs < HCs) in frontal, temporal and cerebellar regions involved in executive function, memory retrieval, and emotional regulation, respectively. These preliminary results support the notion that increased PEL may promote neuroplasticity in IGEs, thus emphasizing the role of physical activity in promoting brain health in people with epilepsy.

Recognition and perception of emotions in juvenile myoclonic epilepsy

OBJECTIVE

Perception and recognition of emotions are fundamental prerequisites of human life. Patients with juvenile myoclonic epilepsy (JME) may have emotional and behavioral impairments that might influence socially desirable interactions. We aimed to investigate perception and recognition of emotions in patients with JME by means of neuropsychological tests and functional magnetic resonance imaging (fMRI).

METHODS

Sixty-five patients with JME (median age = 27 years, interquartile range [IQR] = 23-34) were prospectively recruited at the Department of Neurology, Christian Doppler University Hospital, Paracelsus Medical University, Salzburg, Austria. Patients were compared to 68 healthy controls (median age = 24 years, IQR = 21-31), matched for sex, age, and education. All study participants underwent the Networks of Emotion Processing test battery (NEmo), an fMRI paradigm of "dynamic fearful faces," a structured interview for psychiatric and personality disorders, and comprehensive neuropsychological testing.

RESULTS

JME patients versus healthy controls demonstrated significant deficits in emotion recognition in facial and verbal tasks of all emotions, especially fear. fMRI revealed decreased amygdala activation in JME patients as compared to healthy controls. Patients were at a higher risk of experiencing psychiatric disorders as compared to healthy controls. Cognitive evaluation revealed impaired attentional and executive functioning, namely psychomotor speed, tonic alertness, divided attention, mental flexibility, and inhibition of automated reactions. Duration of epilepsy correlated negatively with parallel prosodic and facial emotion recognition in NEmo. Deficits in emotion recognition were not associated with psychiatric comorbidities, impaired attention and executive functions, types of seizures, and treatment.

SIGNIFICANCE

This prospective study demonstrated that as compared to healthy subjects, patients with JME had significant deficits in recognition and perception of emotions as shown by neuropsychological tests and fMRI. The results of this study may have importance for psychological/psychotherapeutic interventions in the management of patients with JME.

Outpatient visit behavior in patients with epilepsy: Generalized Epilepsy is more frequently non-attendance than Focal Epilepsy

BACKGROUND

Patients with epilepsy (PWE), especially those with Idiopathic Epilepsy (GE), are at a high risk of disadvantage caused by non-adherence. It has been suggested that medical visit behavior may be a surrogate indicator of medication adherence. We hypothesized that patients with IGE would adhere poorly to visits.

METHODS

This was a retrospective study of PWE who visited the Department of Psychiatry and Neurology at Hokkaido University Hospital between January 2017 and December 2019. Demographic and clinical information on PWE were extracted from medical records and visit data from the medical information system. Non-attendance of outpatient appointments was defined as "not showing up for the day of an appointment without prior notice." Mixed-effects logistic regression analysis was conducted with non-attendance as the objective variable.

RESULTS

Of the 9151 total appointments, 413 were non-attendances, with an overall non-attendance rate of 4.5%. IGE was a more frequent non-attendance than Focal Epilepsy (FE) (odds ratio (OR) 1.94; 95% confidence interval (CI) 1.17-3.21; p = 0.010). History of public assistance receipt was associated with higher non-attendance (OR 2.04; 95% CI 1.22-3.43; p = 0.007), while higher education (OR 0.64; 95% CI 0.43-0.93; p = 0.021) and farther distance to a hospital (OR 0.33; 95% CI 0.13-0.88; p = 0.022), and higher frequency of visits (OR 0.18; 95% CI 0.04-0.86; p = 0.031) were associated with fewer non-attendances. In a subgroup analysis of patients with GE, women were associated with fewer non-attendance (OR 0.31; 95% CI 0.14-0.72; p = 0.006).

CONCLUSIONS

GE was more frequent in the non-attendance group than in the FE group. Among patients with GE, females were found to have non-attendance less frequently; however, there was no clear difference in the odds of non-attendance between Juvenile Myoclonic Epilepsy (JME) and IGE other than JME.

Impact of JME on quality of life: Does a well-controlled epilepsy also hamper the psychological wellbeing?

PURPOSE

Epilepsy is a stigmatizing disorder and its diagnosis can have important psychosocial consequences on individuals, severely impacting their quality of life(QOL). There are numerous studies which have seen an adverse impact on the psychosocial aspects of life in patients with intractable epilepsy. The aim of this study was to assess the QOL in adult and adolescent patients with JME, which is largely a well-controlled form of epilepsy.

METHODOLOGY

This was a hospital based cross-sectional observational study comprising of 50 JME patients. QOLIE-31-P and QOLIE-AD-48 questionnaires were used to assess QOL in adults & adolescents(11-17 years) respectively. The Mini international neuropsychiatric interview-version 7.0.2 and Brief psychiatric rating scale were used for screening of underlying psychopathology and if, the screening tests were positive then they were further evaluated and classified using DSM V and ICD 10.

RESULTS

The mean QOLIE-31-P score was 64.65 ± 15.74. Majority of the adult patients had fair QOL (poor, fair and good QOL scores in 18 %, 54 % and 28 % respectively). Subscale scores in poor category were for the medication effects and pertaining to seizure worry.Among adolescent patients, the mean QOLIE 48 AD score was 69.15 ± 13.13. 50 % had fair QOL. Amongst those with poor QOL, majority of poor scores were for the attitude towards epilepsy. The QOL scores were significantly poorer in patients with uncontrolled seizures. 78 % of the patients had comorbid anxiety and depression, however syndromic psychiatric diagnosis was seen in 10.25 % and 2.56 % for anxiety and depression respectively. Presence of psychiatric symptoms did not influence QOL scores.

CONCLUSION

QOL, in well controlled JME, is fair in majority of patients. QOL might improve if seizure worry is addressed and patients are educated about medication effects at the time of initial diagnosis. Vast majority of patients may experience minor psychiatric issues, which do need addressal for formulating a holistic and individualized treatment plan.

A cognitive rehabilitation program to improve hot and cool executive dysfunction in juvenile myoclonic epilepsy: Preliminary findings

OBJECTIVE

Executive and attentional deficits are often described in Juvenile Myoclonic Epilepsy (JME). We aimed to evaluate the short-term impact of rehabilitation developed for the most frequent cognitive deficits of persons with JME.

METHODS

Thirty-three patients entered this study which consisted of 12 individual sessions once a 60-minute week, divided into planning/organization, attention, and impulsivity. Twenty-seven patients finished the protocol, and all patients had pre-and-post evaluations from neuropsychological tests and self-rating questionnaires. Generalized Estimating Equations (GEE) inferential statistics were used to verify the protocol's effect, and a 95% confidence interval was adopted.

RESULTS

We found significant improvement in selective attention (TMT A [p < 0.01] and Stroop test 2 [p = 0.03]), inhibitory control (Stroop test 3 [p = 0.02], FAS [p < 0.01], CPT commissions [p < 0.01]), mental flexibility [WCST categories p < 0.01] and implicit decision making (IGT blocks A [p < 0.01], B [p = 0.02], C [p < 0.01] and D [p < 0.01]). All components of the Behavioral Rating Index of Executive Functions metacognition index and the general quotient had significant improvement (initiative [p ≤ 0.01], working memory [p ≤ 0.01], planning and organization [p ≤ 0.01], task monitor [p = 0.02] and organization of materials [p = 0.02]). Regarding the Behavioral Regulation Index, the "Emotional Control" was improved [p = 0.03]. The attentional component and general scores of the Adult Self-Report Scale for Adults also changed significantly [p ≤ 0.01].

SIGNIFICANCE

Executive function and attention had an improvement in objective and subjective tests. The context-dependent reactive mechanism of impulsivity improved in instruments based on the ecological evaluation. Our findings, though preliminary due to a lack of controls and practice effect corrections, support that cognitive rehabilitation may be a valuable resource to alleviate cognitive deficits in patients with JME.

Neuropsychological profile and drug treatment response in Idiopathic Generalized Epilepsy

PURPOSE

The endophenotype of Idiopathic Generalized Epilepsies (IGE) comprises distinct neuropsychological deficits compared to normal controls. It is unknown if the severity of features of the endophenotype correlates with resistance to anti-seizure medication. Therefore, we here studied the association of neuropsychological profiles with treatment response.

METHODS

We evaluated 106 Danish patients aged ≥18 and diagnosed with IGE using a neuropsychological test battery comprising tests for executive dysfunction, visual attention, episodic memory, and verbal comprehension. Tests were complemented by the Purdue Pegboard test. Patients with suspected ongoing psychogenic non-epileptic seizures were excluded.

RESULTS

At testing, 72 patients were seizure free, and 34 patients had recent seizures despite anti-seizure medication. As compared to age corrected Danish normative values, IGE patients showed significant impairments in semantic fluency and performed significantly worse in the Purdue Pegboard test. The vocabulary subtest of the WAIS-IV suggested lower verbal comprehension in IGE patients. We found no signs of memory impairment. Comparisons between results of the test battery, drug resistance, and the different IGE subsyndromes revealed consistent null-associations in various predefined and exploratory univariate and multivariate analyses.

CONCLUSION

We here found and confirmed the distinct neuropsychological profile comprising impaired executive functions, reduced psychomotor speed, and normal memory previously described in juvenile myoclonic epilepsy. This profile was, however, not restricted to juvenile myoclonic epilepsy but equally affected all IGE patients. The neuropsychological deficits were not significantly associated with drug treatment outcome.

Drug resistance in idiopathic generalized epilepsies: Evidence and concepts

Although approximately 10%-15% of patients with idiopathic generalized epilepsy (IGE)/genetic generalized epilepsy remain drug-resistant, there is no consensus or established concept regarding the underlying mechanisms and prevalence. This review summarizes the recent data and the current hypotheses on mechanisms that may contribute to drug-resistant IGE. A literature search was conducted in PubMed and Embase for studies on mechanisms of drug resistance published since 1980. The literature shows neither consensus on the definition nor a widely accepted model to explain drug resistance in IGE or one of its subsyndromes. Large-scale genetic studies have failed to identify distinct genetic causes or affected genes involved in pharmacokinetics. We found clinical and experimental evidence in support of four hypotheses: (1) "network hypothesis"-the degree of drug resistance in IGE reflects the severity of cortical network alterations, (2) "minor focal lesion in a predisposed brain hypothesis"-minor cortical lesions are important for drug resistance, (3) "interneuron hypothesis"-impaired functioning of γ-aminobutyric acidergic interneurons contributes to drug resistance, and (4) "changes in drug kinetics"-genetically impaired kinetics of antiseizure medication (ASM) reduce the effectiveness of available ASMs. In summary, the exact definition and cause of drug resistance in IGE is unknown. However, published evidence suggests four different mechanisms that may warrant further investigation.

Limited Ability to Adjust N2 Amplitude During Dual Task Walking in People With Drug-Resistant Juvenile Myoclonic Epilepsy

Juvenile myoclonic epilepsy (JME) is one of the most common epileptic syndromes; it is estimated to affect 1 in 1,000 people worldwide. Most people with JME respond well to medication, but up to 30% of them are drug-resistant. To date, there are no biomarkers for drug resistance in JME, and the poor response to medications is identified in retrospect. People with JME have frontal dysfunction manifested as impaired attention and difficulties in inhibiting habitual responses and these dysfunctions are more pronounced in drug-resistant individuals. Frontal networks play an important role in walking and therefore, gait can be used to overload the neural system and expose subtle changes between people with drug-responsive and drug-resistant JME. Electroencephalogram (EEG) is a promising tool to explore neural changes during real-time functions that combine a cognitive task while walking (dual tasking, DT). This exploratory study aimed to examine the alteration in electrical brain activity during DT in people with drug-responsive and drug-resistant JME. A total of 32 subjects (14 males and 18 females) participated: 11 drug-responsive (ages: 31.50 ± 1.50) and 8 drug-resistant (27.27 ± 2.30) people with JME, and 13 healthy controls (29.46 ± 0.69). The participants underwent EEG examination during the performance of the visual Go/NoGo (vGNG) task while sitting and while walking on a treadmill. We measured latencies and amplitudes of N2 and P3 event-related potentials, and the cognitive performance was assessed by accuracy rate and response time of Go/NoGo events. The results demonstrated that healthy controls had earlier N2 and P3 latencies than both JME groups (N2: p = 0.034 and P3: p = 0.011), however, a limited ability to adjust the N2 amplitude during walking was noticeable in the drug-resistant compared to drug-responsive. The two JME groups had lower success rates (drug-responsive p < 0.001, drug-resistant p = 0.004) than healthy controls, but the drug-resistant showed longer reaction times compared to both healthy controls (p = 0.033) and drug-responsive (p = 0.013). This study provides the first evidence that people with drug-resistant JME have changes in brain activity during highly demanding tasks that combine cognitive and motor functions compared to people with drug-responsive JME. Further research is needed to determine whether these alterations can be used as biomarkers to drug response in JME.

Impulsivity traits in eyelid myoclonia with absences

PURPOSE

Eyelid myoclonia with absences (EMA) shares some clinical characteristics with juvenile myoclonic epilepsy (JME), in which impulsivity traits have been described. Aim of the study was to evaluate whether EMA patients could present a peculiar behavioural profile.

METHODS

Patients with EMA, JME and healthy controls (HCs) were enrolled. Subjects with intellectual quotient <80 were excluded from the study. All the enrolled subjects underwent the Italian version of the Barratt Impulsiveness Scale (BIS-11) and the three dimensions of impulsivity (motor, attentional-cognitive and nonplanning impulsivity) were considered.

RESULTS

Seventeen patients with EMA (12 females [70.6%], age 30.8±10 years), 29 patients with JME (17 females [58.6%], age 29.1±9.7 years) and 31 HCs (15 females [48.4%], age 27.6±5.8 years) were enrolled. Both EMA and JME patients presented a borderline significantly higher BIS total score than HCs (p=0.064). EMA patients presented a significantly higher BIS nonplanning subscore than JME patients and HCs (p=0.001).

CONCLUSION

The study showed the presence of peculiar behavioral characteristics in EMA patients, slightly different from patients with JME.

Social outcome and psychiatric comorbidity of generalized epilepsies - A case-control study

OBJECTIVE

To investigate social outcome and psychiatric comorbidity of patients with idiopathic/genetic generalized epilepsies (IGEs) and its subtypes (epilepsy with generalized tonic-clonic seizures alone [EGTCS], juvenile absence epilepsy [JAE], and juvenile myoclonic epilepsy [JME]).

METHODS

A cohort of 402 adult patients with IGE from the Danish island Funen was matched with 4020 randomly selected geography-, age-, and sex-matched controls via the Danish Civil Registration System. Based on register data, we compared social status measured by cohabitant status, educational attainment, income, affiliation to labor market, and psychiatric comorbidity.

RESULTS

As compared to controls, patients with IGE had similar cohabitant status but fewer children (no children: 59.0% vs 50.9%), and lower educational level (primary school only: 46.0% vs 37.3%), employment rate (outside of workforce: 56.7% vs 46.5%), and income (low income: 32.6% vs 24.9%) (P < 0.001 for all comparisons). Having IGE was associated with higher a proportion of psychiatric comorbidity (IGE, 22.6%; controls, 13.0%) (P < 0.001). Seizure-free patients did not differ from controls; patients with persistent seizures had lower incomes and employment rates. In the IGE subgroup analyses, JME was associated with worse social status in all parameters studied (eg, 65.9% of JME patients were outside the workforce vs 44.5% of matched controls; P < 0.001), whereas no adverse social status was identified in patients with EGTCS and JAE.

SIGNIFICANCE

Patients with IGE in general and JME in particular have poorer social status and more psychiatric comorbidity than matched population controls without epilepsy. Poor seizure control was associated with social status and may contribute to negative socioeconomic consequences associated with IGE.

Trait impulsivity in Juvenile Myoclonic Epilepsy

Objective

Impulsivity is a multidimensional construct that can predispose to psychopathology. Meta‐analysis demonstrates an association between response impulsivity and Juvenile Myoclonic Epilepsy (JME), a common genetic generalized epilepsy. Here, we test the hypotheses that trait impulsivity is (i) elevated in JME compared to controls; (ii) moderated by specific seizure characteristics; and (iii) associated with psychiatric adverse effects of antiepileptic drugs (AEDs).

Methods

322 participants with JME and 126 age and gender‐matched controls completed the Barratt’s Impulsiveness Scale (BIS‐brief) alongside information on seizure history and AED use. We compared group BIS‐brief scores and assessed associations of JME BIS‐brief scores with seizure characteristics and AED adverse effects.

Results

The mean BIS‐brief score in JME was 18.1 ± 4.4 compared with 16.2 ± 4.1 in controls (P = 0.0007). Elevated impulsivity was associated with male gender (P = 0.027), frequent absence seizures (P = 0.0004) and lack of morning predominance of myoclonus (P = 0.008). High impulsivity significantly increased the odds of a psychiatric adverse event on levetiracetam (P = 0.036), but not any other psychiatric or somatic adverse effects.

Interpretation

Trait impulsivity is elevated in JME and comparable to scores in personality and neurotic disorders. Increased seizure frequency and absence of circadian seizure pattern moderate BIS score, suggesting disruption of both cortico‐striatal and thalamocortical networks as a shared mechanism between seizures and impulsivity in JME. These findings warrant consideration of impulsivity as a distinct target of intervention, and as a stratifying factor for AED treatment in JME, and perhaps other types of epilepsy. The role of impulsivity in treatment adherence and psychosocial outcome requires further investigation.

Evaluating Executive Functions in Patients with Juvenile Myoclonic Epilepsy Using Frontal Assessment Battery

Objective

In this study, we aimed to evaluate the executive profile of juvenile myoclonic epilepsy (JME) patients using the Frontal Assessment Battery (FAB) as a bedside screening tool and investigate its association with seizure proximity, family history of epilepsy, and polytherapy/monotherapy with antiepileptic drugs (AEDs).

Background

JME patients have deficits in various aspects of executive functions. FAB has proved to be a useful tool for evaluating executive functions in clinical settings.

Methods

Thirty-one JME patients and 110 healthy controls (HCs) were enrolled in this study. The participants were assessed using six subsets of FAB, including conceptualization, mental flexibility, motor programming, sensitivity to interference, inhibitory control, and environmental autonomy.

Results

Compared to HCs, JME patients showed lower scores in conceptualization, mental flexibility, programming, sensitivity to interference, and total FAB. The number of AEDs (polytherapy versus monotherapy) and duration of time since the last seizure had no significant effect on FAB scores in JME patients. We found significant associations between disease duration and conceptualization, mental flexibility, inhibitory control, and total FAB score only in JME patients with recent seizure. Finally, receiver operating characteristic (ROC) analysis showed area under the curve (AUC) of 0.971 (95% confidence interval (CI): 0.947–0.994) for FAB total score, 0.933 for conceptualization (95% CI: 0.973-894), and 0.836 for mental flexibility (95% CI: 0.921-751).

Conclusions

In summary, JME patients had deficits in different aspects of executive functions. FAB is a useful clinical tool for evaluation of executive functions in JME patients.

Seizure control and anxiety: Which factor plays a major role in social adjustment in patients with Juvenile Myoclonic Epilepsy?

PURPOSE

This study aimed to determine the presence of anxiety disorder and severity of anxiety symptoms in an extensive series of consecutive patients with JME and its association with epilepsy-related factors. In addition, we evaluated the impact of anxiety and clinical variables on social adjustment.

METHODS

We prospectively evaluated 112 (56.2 % females, mean age 27.2 years) patients with an electroclinical diagnosis of JME and 61 (52.4 % females, mean age 29.3 years) healthy controls. Anxiety symptoms were assessed by the State and Trait Anxiety Inventory (STAI). Social functioning was addressed with Self-Report Social Adjustment Scale (SAS). The patient group was also evaluated with a psychiatric interview.

RESULTS

Patients with JME presented more severe anxiety symptoms and worse social adjustment compared with controls. The presence of anxiety disorder and the severity of anxiety symptoms was associated with frequent seizures - generalized tonic-clonic seizures (p = 0.008) and drug-resistant epilepsy (p = 0.021). Regarding social adjustment, the severity of anxiety symptoms was associated with lower economic adjustment (p = 0.039), while the presence of anxiety disorder impacted family relationships (p 0.025). The presence of hard-to-control myoclonic seizure was associated with lower scores on work (p = 0.019), leisure activities (p = 0.008), family relationship (p = 0.022) and overall social adjustment (p = 0.038).

CONCLUSION

Patients with JME have severe anxiety symptoms and worse social adjustment. Anxiety disorder and symptoms were associated with frequent seizures and drug-resistant epilepsy. Epilepsy-related factors and anxiety impaired distinct aspects of social functioning.

Meta-analysis of response inhibition in juvenile myoclonic epilepsy

BACKGROUND

Patients with juvenile myoclonic epilepsy (JME) show evidence of cognitive impulsivity that may be linked to later adverse psychosocial outcomes. Here, we quantify the strength of association and estimate effect size (ES) of response inhibition by pooling available evidence in a meta-analysis.

METHODS

We conducted a systematic review of the literature using Ovid MEDLINE and Ovid EMBASE databases (covering 2001-2019) with a search strategy using combinations of the specific Medical Subject Headings (MeSH) terms 'juvenile myoclonic epilepsy, cognitive impulsivity, response inhibition, Stroop, cognition, personality, traits' using the 'explode' feature where possible. We also searched within references of retrieved articles. We included studies reporting ESs describing established measures of response inhibition in teenage and adult patients with JME.

RESULTS

Using the ESs pooled from 16 studies comprising 1047 patients and controls, we found ESs for response inhibition to be homogeneous with a significant moderate mean ES of d = 0.50 (95% confidence interval [CI]: 0.37-0.63).

CONCLUSIONS

We confirm that reduced response inhibition is a consistently observed homogeneous trait in patients with JME.

Cognitive functioning in new-onset juvenile myoclonic epilepsy

PURPOSE

Juvenile myoclonic epilepsy (JME) is a common genetic generalized epilepsy syndrome. Adult patients with JME have shown a neuropsychological profile suggestive of subtle frontal dysfunction, but studies of cognitive functioning in the early phases of JME are rare. We analyzed the cognitive performance data of 18 patients who had undergone a neuropsychological assessment either at the time of JME diagnosis and before the initiation of an antiepileptic drug (AED) treatment (11 patients) or during the first 6 years after JME diagnosis (seven patients).

METHODS

The cognitive performance of the18 patients with JME (mean age: 18.1, range: 15-33 years) and 18 healthy controls (mean age: 18.7, range: 15-25 years) was compared in a retrospective study. The assessed cognitive domains were visuomotor speed, attention, executive function, and verbal memory.

RESULTS

The patients with JME and the healthy controls did not differ in any of the assessed cognitive domains. The clinical variables did not correlate to cognitive performance. Furthermore, cognitive performance did not differ between the patients evaluated at the time of diagnosis and before the initiation of AEDs and the patients evaluated during the first 6 years after diagnosis and with an AED treatment.

CONCLUSIONS

The cognitive performance of patients with new-onset JME was similar to healthy controls. We could not detect the frontal dysfunction that has been suggested to be associated with JME. Patients were in adolescence or early adulthood with a short duration of epilepsy, which may have contributed to the discovery of no cognitive impairments.

Cognitive Function in Genetic Generalized Epilepsies: Insights From Neuropsychology and Neuroimaging

Genetic generalized epilepsies (GGE), previously called idiopathic generalized epilepsies, constitute about 20% of all epilepsies, and include childhood absence epilepsy, juvenile absence epilepsy, juvenile myoclonic epilepsy, and epilepsy with generalized tonic-clonic seizures alone (CAE, JAE, JME, and GGE-GTCS, respectively). GGE are characterized by high heritability, likely underlain by polygenetic mechanisms, which may relate to atypical neurodevelopmental trajectories. Age of onset ranges from pre-school years, for CAE, to early adulthood for GGE-GTCS. Traditionally, GGE have been considered benign, a belief contrary to evidence from neuropsychology studies conducted over the last two decades. In JME, deficits in executive and social functioning are common findings and relate to impaired frontal lobe function. Studies using neuropsychological measures and cognitive imaging paradigms provide evidence for hyperconnectivity between prefrontal and motor cortices, aberrant fronto-thalamo-cortical connectivity, and reduced fronto-cortical and subcortical gray matter volumes, which are associated with altered cognitive performance. Recent research has also identified associations between abnormal hippocampal morphometry and fronto-temporal activation during episodic memory. Longitudinal studies on individuals with newly diagnosed JME have observed cortical dysmaturation, which is paralleled by delayed cognitive development compared to the patients' peers. Comorbidities and cognitive deficits observed in other GGE subtypes, such as visuo-spatial and language deficits in both CAE and JAE, have also been correlated with atypical neurodevelopment. Although it remains unclear whether cognitive impairment profiles differ amongst GGE subtypes, effects may become more pronounced with disease duration, particularly in absence epilepsies. Finally, there is substantial evidence that patients with JME and their unaffected siblings share patterns of cognitive deficits, which is indicative of an underlying genetic etiology (endophenotype), independent of seizures and anti-epileptic medication.

The Timing, Nature, and Range of Neurobehavioral Comorbidities in Juvenile Myoclonic Epilepsy

BACKGROUND

Accumulating evidence suggests that considerable cognitive and psychiatric comorbidity is associated with juvenile myoclonic epilepsy, for which the etiology remains controversial. Our goal was to comprehensively characterize the status of multiple neurobehavioral comorbidities in youth with new- or recent-onset juvenile myoclonic epilepsy, before effects of chronic seizures and medications.

METHODS

A total of 111 children aged eight to 18 years (41 new- or recent-onset juvenile myoclonic epilepsy and 70 first-degree cousin controls) underwent neuropsychological assessment (attention, executive, verbal, perceptual, speed), structured review of need for supportive academic services, parent reports of behavior and executive function (Child Behavior Checklist and Behavior Rating Inventory of Executive Function), and formal structured psychiatric interview and diagnosis (Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version).

RESULTS

Children with juvenile myoclonic epilepsy performed worse than controls across all tested cognitive domains (F(1,105) = 3.85, P < 0.01), utilized more academic services (47% versus 19%, P = 0.002), had more parent-reported behavioral problems and dysexecutive function with lower competence (P < 0.001), and had a higher prevalence of current Axis I diagnoses (attention-deficit/hyperactivity disorder, depression, and anxiety; 54% versus 23%, P = 0.001). Academic and psychiatric problems occurred antecedent to epilepsy onset compared with comparable timeline in controls.

CONCLUSION

Comprehensive assessment of cognitive, academic, behavioral, and psychiatric comorbidities in youth with new- or recent-onset juvenile myoclonic epilepsy reveals a pattern of significantly increased neurobehavioral comorbidities across a broad spectrum of areas. These early evident comorbidities are of clear clinical importance with worrisome implications for future cognitive, behavioral, and social function. It is important for health care providers to avoid delays in intervention by assessing potential comorbidities early in the course of the disorder to optimize their patients' social, academic and behavioral progress.

Dissociation between decision making under ambiguity and risk in patients with juvenile myoclonic epilepsy

INTRODUCTION

Decision making (DM) is one aspect of impulsivity that can be defined by the ability to decide between two or more options in a given situation. To date, there are at least two types of DM that differ in the level of uncertainty, and how much information about consequences is provided. In this study, we aimed to evaluate the two domains of DM - under risk and ambiguous - with a comprehensive evaluation in a group of patients with juvenile myoclonic epilepsy (JME), and correlate with patients' characteristics, clinical variables, and neuropsychological evaluation for executive functions.

METHODS

We evaluated 35 patients with JME and 39 healthy controls using the Iowa Gambling Task for DM under ambiguity and the Game Dice Task for DM under risk. We assessed the performance in Iowa Gambling Task and Game Dice Task through net scores, safe and risky choices, besides the type of decisions across time.

RESULTS

Patients with JME had a higher number of risky choices compared to controls in the Game Dice Task. There was no significant difference between patients and controls in the Iowa Gambling Task. However, patients with higher seizure frequency had worse scores on decks C and D (safe choices) from the Iowa Gambling Task.

CONCLUSION

Patients with JME have worse performance on DM under risk. The same was not observed for DM under ambiguity. Epilepsy-related factors and the presence of psychiatric disorders, but not executive dysfunction, were associated with a lower tendency for safe choices. These findings showed a dissociation between DM processes in patients with JME and a tendency to make disadvantageous decisions with measurable risks.

The role of task-based neural activation research in understanding cognitive deficits in pediatric epilepsy

Children with epilepsy can experience significant cognitive dysfunction that can lead to academic underachievement. Traditionally believed to be primarily due to the effects of factors such as the chronicity of epilepsy, medication effects, or the location of the primary epileptogenic lesion;, recent evidence has indicated that disruption of cognition-specific distributed neural networks may play a significant role as well. Specifically, over the last decade, researchers have begun to characterize the mechanisms underlying disrupted cognitive substrates by evaluating neural network abnormalities observed during specific cognitive tasks, using task-based functional magnetic resonance imaging (fMRI). This targeted review assesses the current literature investigating the relationship between neural network abnormalities and cognitive deficits in pediatric epilepsy. The findings indicate that there are indeed neural network abnormalities associated with deficits in executive function, language, processing speed, and memory. Overall, cognitive dysfunction in pediatric epilepsy is associated with a decrease in neural network activation/deactivation as well as increased recruitment of brain regions not typically related to the specific cognitive task under investigation. The research to date has focused primarily on children with focal epilepsy syndromes with small sample sizes and differing research protocols. More extensive research in children with a wider representation of epilepsy syndromes (including generalized epilepsy syndromes) is necessary to fully understand these relationships and begin to identify underlying cognitive phenotypes that may account for the variability observed across children with epilepsy. Furthermore, more uniformity in fMRI protocols and neuropsychological tasks would be ideal to advance this literature.

Subtle Brain Developmental Abnormalities in the Pathogenesis of Juvenile Myoclonic Epilepsy

Juvenile myoclonic epilepsy (JME), a lifelong disorder that starts during adolescence, is the most common of genetic generalized epilepsy syndromes. JME is characterized by awakening myoclonic jerks and myoclonic-tonic-clonic (m-t-c) grand mal convulsions. Unfortunately, one third of JME patients have drug refractory m-t-c convulsions and these recur in 70-80% who attempt to stop antiepileptic drugs (AEDs). Behavioral studies documented impulsivity, but also impairment of executive functions relying on organization and feedback, which points to prefrontal lobe dysfunction. Quantitative voxel-based morphometry (VBM) revealed abnormalities of gray matter (GM) volumes in cortical (frontal and parietal) and subcortical structures (thalamus, putamen, and hippocampus). Proton magnetic resonance spectroscopy (MRS) found evidence of dysfunction of thalamic neurons. White matter (WM) integrity was disrupted in corpus callosum and frontal WM tracts. Magnetic resonance imaging (MRI) further unveiled anomalies in both GM and WM structures that were already present at the time of seizure onset. Aberrant growth trajectories of brain development occurred during the first 2 years of JME diagnosis. Because of genetic origin, disease causing variants were sought, first by positional cloning, and most recently, by next generation sequencing. To date, only six genes harboring pathogenic variants (GABRA1, GABRD, EFHC1, BRD2, CASR, and ICK) with Mendelian and complex inheritance and covering a limited proportion of the world population, are considered as major susceptibility alleles for JME. Evidence on the cellular role, developmental and cell-type expression profiles of these six diverse JME genes, point to their pathogenic variants driving the first steps of brain development when cell division, expansion, axial, and tangential migration of progenitor cells (including interneuron cortical progenitors) sculpture subtle alterations in brain networks and microcircuits during development. These alterations may explain "microdysgenesis" neuropathology, impulsivity, executive dysfunctions, EEG polyspike waves, and awakening m-t-c convulsions observed in JME patients.

Drug-Resistant Juvenile Myoclonic Epilepsy: Misdiagnosis of Progressive Myoclonus Epilepsy

Juvenile myoclonic epilepsy (JME) is a common epilepsy syndrome characterized by bilateral myoclonic and tonic-clonic seizures typically starting in adolescence and responding well to medication. Misdiagnosis of a more severe progressive myoclonus epilepsy (PME) as JME has been suggested as a cause of drug-resistance. Medical records of the Epilepsy Center Hessen-Marburg between 2005 and 2014 were automatically selected using keywords and manually reviewed regarding the presence of a JME diagnosis at any timepoint. The identified patients were evaluated regarding seizure outcome and drug resistance according to ILAE criteria. 87/168 identified JME patients were seizure-free at last follow-up including 61 drug-responsive patients (group NDR). Seventy-eight patients were not seizure-free including 26 drug-resistant patients (group DR). Valproate was the most efficacious AED. The JME diagnosis was revised in 7 patients of group DR including 6 in whom the diagnosis had already been questioned or revised during clinical follow-up. One of these was finally diagnosed with PME (genetically confirmed Lafora disease) based on genetic testing. She was initially reviewed at age 29 yrs and considered to be inconsistent with PME. Intellectual disability (p = 0.025), cognitive impairment (p < 0.001), febrile seizures in first-degree relatives (p = 0.023) and prominent dialeptic seizures (p = 0.009) where significantly more frequent in group DR. Individuals with PME are rarely found among drug-resistant alleged JME patients in a tertiary epilepsy center. Even a very detailed review by experienced epileptologists may not identify the presence of PME before the typical features evolve underpinning the need for early genetic testing in drug-resistant JME patients.

A pilot study of combined endurance and resistance exercise rehabilitation for verbal memory and functional connectivity improvement in epilepsy

Memory impairment is common in persons with epilepsy (PWE), and exercise may be a strategy for its improvement. In this pilot study, we hypothesized that exercise rehabilitation would improve physical fitness and verbal memory and induce changes in brain networks involved in memory processes. We examined the effects of combined endurance and resistance exercise rehabilitation on memory and resting state functional connectivity (rsFC). Participants were randomized to exercise (PWE-E) or control (PWE-noE). The exercise intervention consisted of 18 supervised sessions on nonconsecutive days over 6 weeks. Before and after the intervention period, both groups completed self-report assessments (Short Form-36 (SF-36), Baecke Questionnaire (BQ) of habitual physical activity, and Profile of Mood States (POMS)), cognitive testing (California Verbal Learning Test-II (CVLT-II)), and magnetic resonance imaging (MRI); PWE-E also completed exercise performance tests. After completing the study, PWE-noE were offered cross-over to the exercise arm. There were no differences in baseline demographic, clinical, or assessment variables between 8 PWE-noE and 9 PWE-E. Persons with epilepsy that participated in exercise intervention increased maximum voluntary strength (all strength tests p < 0.05) and exhibited nonsignificant improvement in cardiorespiratory fitness (p = 0.15). Groups did not show significant changes in quality of life (QOL) or habitual physical activity between visits. However, there was an effect of visit on POMS total mood disturbance (TMD) measure showing improvement from baseline to visit 2 (p = 0.023). There were significant group by visit interactions on CVLT-II learning score (p = 0.044) and total recognition discriminability (d') (p = 0.007). Persons with epilepsy that participated in exercise intervention had significant reductions in paracingulate rsFC with the anterior cingulate and increases in rsFC for the cerebellum, thalamus, posterior cingulate cortex (PCC), and left and right inferior parietal lobule (IPL) (corrected p < 0.05). Change in CVLT-II learning score was associated with rsFC changes for the paracingulate cortex (r_S = -0.67; p = 0.0033), left IPL (r_S = 0.70; p = 0.0019), and right IPL (r_S = 0.71; p = 0.0015) while change in d' was associated with change in cerebellum rsFC to angular/middle occipital gyrus (r_S = 0.68; p = 0.0025). Our conclusion is that exercise rehabilitation may facilitate verbal memory improvement and brain network functional connectivity changes in PWE and that improved memory performance is associated with changes in rsFC. A larger randomized controlled trial of exercise rehabilitation for cognitive improvement in PWE is warranted.

Anxiety and depression symptoms disrupt resting state connectivity in patients with genetic generalized epilepsies

OBJECTIVE

To analyze the lifetime trajectories in genetic generalized epilepsies (GGEs) and investigate the impact of symptoms of anxiety and depression on resting state functional connectivity (FC).

METHODS

Seventy-four GGE patients were classified according to the pharmacological response as seizure-free (12 patients), pharmacoresistant (PhR; 14 patients), and fluctuating (FL; 48 patients). Fifty-four subjects completed both the Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI), and 38 also underwent 3-T resting state functional magnetic resonance imaging. These 38 patients were subdivided into a positive group (13 patients with concurrent symptoms of depression and anxiety) and a negative group (21 asymptomatic patients and four with mild anxiety or depression symptoms). For FC analysis of resting state networks, we matched 38 healthy asymptomatic volunteers and used the UF2C toolbox running on MATLAB2017/SPM12.

RESULTS

The PhR group presented shorter duration of epilepsy (P = 0.016) and follow-up (P < 0.001) compared to the FL group. The PhR group showed higher levels (median = 20) on the BAI and BDI. Myoclonic seizures were the most difficult to control, as 50% of subjects persisted with them at last appointment, compared to generalized tonic-clonic seizures and absence seizures (<40%). Patients with concurrent anxiety and depression symptoms were 7.7 times more likely to exhibit pharmacoresistant seizures, although an increase of 1 year of epilepsy duration was associated with a decrease in the odds of presenting pharmacoresistance by a factor of 0.9. Overall, FC was altered between default mode network (DMN) and visuospatial/dorsal attention. However, only the positive group displayed abnormal FC between DMN and left executive control network, and between salience and visuospatial/dorsal attention.

SIGNIFICANCE

Our findings may help clinicians to have a better understanding of GGE clinical course and increase attention to the potential relationship of psychopathologies and brain connectivity.

Higher IQ in juvenile myoclonic epilepsy: Dodging cognitive obstacles and "masking" impairments

Executive deficits and impulsiveness are extensively reported in juvenile myoclonic epilepsy (JME). Previous literature suggests that intelligence may mediate these deficits. In this study, we evaluated and compared the performance of adults with JME with high and low intelligence quotient (IQ) and controls on tasks for executive function (EF) and impulsive traits. We investigated the neuropsychological performance of 53 adults with JME and below average IQ (57% women; 26.9 [±7.88] years; mean IQ: 89.8 [±5.1]), 26 adults with JME and average or above average IQ (53.8% women; 28.2 [±9.33] years; mean IQ: 110.7 [±8.3]), 38 controls with below average IQ (55% women; 28.4 [±8.4] years; mean IQ: 90.1 [±5.8]), and 31 controls with average or above average IQ (61.3% women; 32.20 [±11.3] years; mean IQ: 111.6 [±10.5]) with a comprehensive battery of neuropsychological tests that measure executive/attentional function. Impulsive traits were assessed using the Cloninger et al.'s Temperament and Character Inventory (novelty seeking (NS) domain). The group with JME with higher IQ presented worse performance compared with controls with higher IQ on Controlled Oral Word Association (COWA) and Wisconsin Card Sorting Test (WCST) (errors). This group showed worse performance than controls with lower IQ on Stroop Color-Word Test (SCT) 1, Trail Making (TM) A, COWA, and WCST (errors). Patients with lower IQ showed worse performance than controls with higher IQ on Digit Span Forward (DSF), Digit Span Backward (DSB), SCT1, SCT2, SCT3, TM A, COWA, and WCST (errors and failure to maintain set). Patients with lower IQ showed worse performance than controls with lower IQ on DSF, DSB, SCT1, SCT2, SCT3, TM A, TM B, COWA, and WCST (errors and failure to maintain set). Patients from groups with low and high IQ showed higher scores than controls with higher and lower IQ on impulsivity for NS1 and NS2 (except for patients with higher IQ versus controls with lower IQ). Adults with JME and higher IQ show less evidence of EF deficits compared with those with JME and below average IQ, suggesting that a higher degree of intellectual efficiency may act as a compensatory mechanism. However, it does not minimize some aspects of impulsive traits. Patients with JME and higher cognitive reserve may create strategies to dodge their cognitive obstacles. In this context, intelligence may protect and, at the same time, "mask" impairments that could be detected earlier.

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

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

Juvenile myoclonic epilepsy refractory to treatment in a tertiary referral center

INTRODUCTION

Juvenile myoclonic epilepsy (JME) is an epileptic syndrome often regarded as one in which seizures are relatively easy to control. Individuals with JME, however, often require lifelong therapy to remain seizure-free, and a few have refractory epilepsy. We ascertained a population with JME and characterized a subgroup with refractory epilepsy.

MATERIAL AND METHODS

We audited and reviewed clinical records of individuals diagnosed with JME identified via a sample of 6600 individuals in a clinical database from a specialized epilepsy clinic at a tertiary referral center.

RESULTS

We identified 240 people with a diagnosis of JME (146 females), with a mean age at seizure onset of 14.2years (SD: 4.5), and a mean age at diagnosis of 15.6years (SD: 4.9). Clinical phenotypes seen were classic JME phenotype (88%), childhood absence epilepsy evolving into JME (6%), JME with adolescent absences (4%), and JME with astatic seizures (2%). More than a quarter (28%) had a family history of epilepsy. The most commonly used antiepileptic drug (AED) was sodium valproate in 78% of individuals, followed by levetiracetam (64%) and lamotrigine (55%). In the previous year, 47.5% were seizure-free. Using the International League against Epilepsy (ILAE) definitions and considering National Institute for Health and Care Excellence (NICE)-recommended AEDs for this syndrome, 121 individuals (50.4%) were identified as having refractory epilepsy.

DISCUSSION

Juvenile myoclonic epilepsy is often regarded as a benign epileptic syndrome, but in this setting, half of the individuals with JME have refractory epilepsy with only about a quarter of those seizure-free in the previous year. Despite some advances in the understanding of this syndrome, there is still much to do before we can offer all the best outcomes.

Neurocognitive Comorbidities in Pediatric Epilepsy: Lessons in the Laboratory and Clinical Profile

Children with epilepsy are at risk for a variety of neurocognitive comorbidities. Animal models have increased our understanding about the neurobiological mechanisms underlying the association between seizures and these comorbidities. This article starts with an overview of the current data on animal model research, studying the influence of early-life seizures, followed by a summary of potential cellular and molecular mechanisms by which seizures can affect cognitive development. We then describe specific abnormal neuropsychological profiles that accompany specific pediatric epilepsy syndromes. Finally, we offer a potential guideline to the treatment and management of children with epilepsy and its neurocognitive comorbidities.

Proton spectroscopy of the thalamus in a homogeneous sample of patients with easy-to-control juvenile myoclonic epilepsy

Objective

Juvenile myoclonic epilepsy (JME) is a subtype of genetically determined generalized epilepsy that does not present abnormalities on conventional magnetic resonance imaging. The aim of this study was to identify metabolic alterations in the thalamus in a clinically homogeneous sample of patients with easy-to-control JME, using short-echo time proton magnetic resonance spectroscopy (MRS).

Materials and Methods

We performed single-voxel (2 cm × 2 cm × 2 cm), short-echo time (TE = 35 ms) proton MRS of the thalamus in 21 patients with JME and in 14 healthy age-matched controls. We quantified N-acetylaspartate (NAA), total NAA, creatine (Cr), choline, and myo-inositol (MI), as well as the sum of glutamate and glutamine signals, all scaled to internal water content, and we calculated metabolite ratios using Cr as a reference. Values of p < 0.05 were considered significant.

Results

The MI level and the MI/Cr ratio were significantly lower in the thalami of patients diagnosed with JME than in those of the controls. Other metabolites and their ratios did not differ significantly between the two groups.

Conclusion

In our sample of 21 JME patients, we identified lower levels of MI in the thalamus. No significant abnormalities were observed in the concentrations or ratios of other metabolites.

Paradigm Shifts in the Neuropsychology of Epilepsy

This article reviews the major paradigm shifts that have occurred in the area of the application of clinical and experimental neuropsychology to epilepsy and epilepsy surgery since the founding of the International Neuropsychological Society. The five paradigm shifts discussed include: 1) The neurobiology of cognitive disorders in epilepsy - expanding the landscape of syndrome-specific neuropsychological impairment; 2) pathways to comorbidities: bidirectional relationships and their clinical implications; 3) discovering quality of life: The concept, its quantification and applicability; 4) outcomes of epilepsy surgery: challenging conventional wisdom; and 5) Iatrogenic effects of treatment: cognitive and behavioral effects of antiepilepsy drugs. For each area we characterize the status of knowledge, the key developments that have occurred, and how they have altered our understanding of the epilepsies and their management. We conclude with a brief overview of where we believe the field will be headed in the next decade which includes changes in assessment paradigms, moving from characterization of comorbidities to interventions; increasing development of new measures, terminology and classification; increasing interest in neurodegenerative proteins; transitioning from clinical seizure features to modifiable risk factors; and neurobehavioral phenotypes. Overall, enormous progress has been made over the lifespan of the INS with promise of ongoing improvements in understanding of the cognitive and behavioral complications of the epilepsies and their treatment. (JINS, 2017, 23, 791-805).

The new approach to epilepsy classification: Cognition and behavior in adult epilepsy syndromes

The revised terminology and concepts for the organization of seizures and epilepsy proposed by the ILAE Commission on Classification and Terminology in 2010 allows for a number of new opportunities in the study of cognition and behavior in adults. This review examines the literature that has looked for behavioral and cognitive correlates of the newly recognized genetic epilepsies in adults. While some studies report clear cognitive phenotypes associated with specific genetic mutations in adults with epilepsy, others report remarkable clinical heterogeneity. In the second part of this review, we discuss some of the factors that may influence the findings in this literature. Cognitive function is the product of both genetic and environmental influences. Neuropsychological phenotypes under direct genetic influence may be wider and more subtle than specific deficits within discreet cognitive domains and may be reflected in broader, multidimensional measures of cognitive function than those tapped by scores on standardized tests of function. Future studies must be carefully designed to reflect these factors. It is also imperative that studies with negative findings are assigned as much value as those with positive results and published accordingly. This article is part of a Special Issue titled "The new approach to classification: Rethinking cognition and behavior in epilepsy.

Reprint of: The new approach to epilepsy classification: Cognition and behavior in adult epilepsy syndromes

The revised terminology and concepts for the organization of seizures and epilepsy proposed by the ILAE Commission on Classification and Terminology in 2010 allows for a number of new opportunities in the study of cognition and behavior in adults. This review examines the literature that has looked for behavioral and cognitive correlates of the newly recognized genetic epilepsies in adults. While some studies report clear cognitive phenotypes associated with specific genetic mutations in adults with epilepsy, others report remarkable clinical heterogeneity. In the second part of this review, we discuss some of the factors that may influence the findings in this literature. Cognitive function is the product of both genetic and environmental influences. Neuropsychological phenotypes under direct genetic influence may be wider and more subtle than specific deficits within discreet cognitive domains and may be reflected in broader, multidimensional measures of cognitive function than those tapped by scores on standardized tests of function. Future studies must be carefully designed to reflect these factors. It is also imperative that studies with negative findings are assigned as much value as those with positive results and published accordingly. This article is part of a Special Issue titled "The new approach to classification: Rethinking cognition and behavior in epilepsy".