Widespread ripples synchronize human cortical activity during sleep, waking, and memory recall.

Declarative memory encoding, consolidation, and retrieval require the integration of elements encoded in widespread cortical locations. The mechanism whereby such "binding" of different components of mental events into unified representations occurs is unknown. The "binding-by-synchrony" theory proposes that distributed encoding areas are bound by synchronous oscillations enabling enhanced communication. However, evidence for such oscillations is sparse. Brief high-frequency oscillations ("ripples") occur in the hippocampus and cortex and help organize memory recall and consolidation. Here, using intracranial recordings in humans, we report that these ∼70-ms-duration, 90-Hz ripples often couple (within ±500 ms), co-occur (≥ 25-ms overlap), and, crucially, phase-lock (have consistent phase lags) between widely distributed focal cortical locations during both sleep and waking, even between hemispheres. Cortical ripple co-occurrence is facilitated through activation across multiple sites, and phase locking increases with more cortical sites corippling. Ripples in all cortical areas co-occur with hippocampal ripples but do not phase-lock with them, further suggesting that cortico-cortical synchrony is mediated by cortico-cortical connections. Ripple phase lags vary across sleep nights, consistent with participation in different networks. During waking, we show that hippocampo-cortical and cortico-cortical coripples increase preceding successful delayed memory recall, when binding between the cue and response is essential. Ripples increase and phase-modulate unit firing, and coripples increase high-frequency correlations between areas, suggesting synchronized unit spiking facilitating information exchange. co-occurrence, phase synchrony, and high-frequency correlation are maintained with little decrement over very long distances (25 cm). Hippocampo-cortico-cortical coripples appear to possess the essential properties necessary to support binding by synchrony during memory retrieval and perhaps generally in cognition.

Individual- and community-level social determinants of health are associated with cognition in older adults with focal epilepsy.

OBJECTIVE: Epilepsy is associated with significant health disparities, including access to specialized care and adverse outcomes that have been associated with several social determinants of health (SDOH). We sought to examine the relationship between individual- and community-level SDOH and cognitive outcomes in older adults with epilepsy. MATERIALS AND METHODS: We collected clinical, SDOH, and neuropsychological data in 57 older adults with epilepsy. Individual-level SDOH included patient factors (quality of education, income, insurance, marital status) and early-life environmental factors (parental education and occupation, childhood employment). Neighborhood deprivation was measured with the Area Deprivation Index (ADI). Stepwise regressions were conducted to examine the independent contribution of individual-level SDOH to cognitive performance, and Spearman rho correlations were conducted to examine the relationship between ADI and cognitive performance. The SDOH profiles of patients who met the criteria for cognitive impairment were examined. RESULTS: After controlling for clinical variables, patient factors (public health insurance, poorer quality of education) and early-life environmental factors (lower mother's education, lower father's and mother's occupational complexity, history of childhood employment) were significant predictors of lower performance on measures of global cognition, verbal learning and memory, processing speed, and executive function. Higher ADI values (greater disadvantage) were associated with lower scores on global cognitive measures, verbal learning and memory, and executive function. Patients who met criteria for cognitive impairment had, on average, a greater number of adverse SDOH, including lower household incomes and father's education, and higher ADI values compared to those who were cognitively intact. CONCLUSION: We provide new evidence of the role of individual- and community-level SDOH on cognitive outcomes in older adults with epilepsy. This emerging literature highlights the need to examine SDOH beyond epilepsy-related clinical factors. These data could inform the development of interventions focused on increasing access to epilepsy care, education, and resources and promoting brain and cognitive health within the most at-risk communities.

The nested hierarchy of overt, mouthed, and imagined speech activity evident in intracranial recordings.

Recent studies have demonstrated that it is possible to decode and synthesize various aspects of acoustic speech directly from intracranial measurements of electrophysiological brain activity. In order to continue progressing toward the development of a practical speech neuroprosthesis for the individuals with speech impairments, better understanding and modeling of imagined speech processes are required. The present study uses intracranial brain recordings from participants that performed a speaking task with trials consisting of overt, mouthed, and imagined speech modes, representing various degrees of decreasing behavioral output. Speech activity detection models are constructed using spatial, spectral, and temporal brain activity features, and the features and model performances are characterized and compared across the three degrees of behavioral output. The results indicate the existence of a hierarchy in which the relevant channels for the lower behavioral output modes form nested subsets of the relevant channels from the higher behavioral output modes. This provides important insights for the elusive goal of developing more effective imagined speech decoding models with respect to the better-established overt speech decoding counterparts.

A cost analysis of MR-guided laser interstitial thermal therapy for adult refractory epilepsy.

OBJECTIVE: MR-guided laser interstitial thermal therapy (LITT) is used increasingly for refractory epilepsy. The goal of this investigation is to directly compare cost and short-term adverse outcomes for adult refractory epilepsy treated with temporal lobectomy and LITT, as well as to identify risk factors for increased costs and adverse outcomes. METHODS: The National Inpatient Sample (NIS) was queried for patients who received LITT between 2012 and 2019. Patients with adult refractory epilepsy were identified. Multivariable mixed-effects models were used to analyze predictors of cost, length of stay (LOS), and complications. RESULTS: LITT was associated with reduced LOS and overall cost relative to temporal lobectomy, with a statistical trend toward lower incidence of postoperative complications. High-volume surgical epilepsy centers had lower LOS overall. Longer LOS was a significant driver of increased cost for LITT, and higher comorbidity was associated with non-routine discharge. SIGNIFICANCE: LITT is an affordable alternative to temporal lobectomy for adult refractory epilepsy with an insignificant reduction in inpatient complications. Patients may benefit from expanded access to this treatment modality for both its reduced LOS and lower cost.

Impaired Behavioral Pattern Separation in Refractory Temporal Lobe Epilepsy and Mild Cognitive Impairment.

OBJECTIVE: Episodic memory impairment and hippocampal pathology are hallmark features of both temporal lobe epilepsy (TLE) and amnestic mild cognitive impairment (aMCI). Pattern separation (PS), which enables the distinction between similar but unique experiences, is thought to contribute to successful encoding and retrieval of episodic memories. Impaired PS has been proposed as a potential mechanism underling episodic memory impairment in aMCI, but this association is less established in TLE. In this study, we examined behavioral PS in patients with TLE and explored whether profiles of performance in TLE are similar to aMCI. METHOD: Patients with TLE, aMCI, and age-matched, healthy controls (HCs) completed a modified recognition task that relies on PS for the discrimination of highly similar lure items, the Mnemonic Similarity Task (MST). Group differences were evaluated and relationships between clinical characteristics, California Verbal Learning Test-Second Edition scores, and MST performance were tested in the TLE group. RESULTS: Patients with TLE and aMCI demonstrated poorer PS performance relative to the HCs, but performance did not differ between the two patient groups. Neither the side of seizure focus nor having hippocampal sclerosis affected performance in TLE. However, TLE patients with clinically defined memory impairment showed the poorest performance. CONCLUSION: Memory performance on a task that relies on PS was disrupted to a similar extent in TLE and aMCI. The MST could provide a clinically useful tool for measuring hippocampus-dependent memory impairments in TLE and other neurological disorders associated with hippocampal damage.

Clinical characteristics of video-EEG patients: Limited utility of prolonging VEEG study duration beyond 5 days for spell classification.

OBJECTIVE: The objective of the study was to identify the probability of establishing a diagnosis based on the duration of video-electroencephalogram (VEEG) monitoring. Additional aims were to determine whether there is a relationship between clinical characteristics of epilepsy monitoring unit (EMU) patients and VEEG results. METHODS: We studied EMU length of stay and assessed the utility of prolonging studies in patients who had not yet received a diagnosis. Clinical characteristics in 212 consecutive patients admitted for scalp VEEG monitoring were recorded. We collected data including reason for admission, frequency of seizures/spells, gender, age, age at seizure onset, handedness, family history, history of neurologic disease, current and past antiepileptic drugs (AEDs), and prior work-up. Subjects were categorized into five diagnostic groups: epileptic seizures (Epi), nonepileptic events (NEE), mixed epileptic and nonepileptic events (Mixed), nonepileptic events from a physiologic cause (NEEP), and nondiagnostic study without results recorded (ND). RESULTS: The most diagnoses were made during the first day of admission (45%), and by day 3, 82 patients remained without a diagnosis. On day 3, 25 of these patients (33%) received a diagnosis, on day 4, seven (22%) additional patients received a diagnosis, on day 5, 5 patients (35%) received a diagnosis, and by day 6, only one additional patient (11%) was given a diagnosis. Significant differences were found between diagnostic groups for admission reason, duration of EMU stay, age at seizure onset, duration of epilepsy, seizure frequency, and number of current and previously tried AEDs. CONCLUSIONS: Our findings show that the majority of patients are diagnosed in the first 2 days of admission, and we found a limited benefit of prolonging nonsurgical inpatient VEEG studies beyond 5 days for spell/seizure classification. Additionally, patient demographics were significantly different for patients depending on VEEG diagnosis, which can help predict the utility of completing VEEG studies in individual patients.

Differential sensitivity of structural, diffusion, and resting-state functional MRI for detecting brain alterations and verbal memory impairment in temporal lobe epilepsy.

OBJECTIVES: Temporal lobe epilepsy (TLE) is known to affect large-scale gray and white matter networks, and these network changes likely contribute to the verbal memory impairments observed in many patients. In this study, we investigate multimodal imaging patterns of brain alterations in TLE and evaluate the sensitivity of different imaging measures to verbal memory impairment. METHODS: Diffusion tensor imaging (DTI), volumetric magnetic resonance imaging (vMRI), and resting-state functional MRI (rs-fMRI) were evaluated in 46 patients with TLE and 33 healthy controls to measure patterns of microstructural, structural, and functional alterations, respectively. These measurements were obtained within the white matter directly beneath neocortex (ie, superficial white matter [SWM]) for DTI and across neocortex for vMRI and rs-fMRI. The degree to which imaging alterations within left medial temporal lobe/posterior cingulate (LMT/PC) and left lateral temporal regions were associated with verbal memory performance was evaluated. RESULTS: Patients with left TLE and right TLE both demonstrated pronounced microstructural alterations (ie, decreased fractional anisotropy [FA] and increased mean diffusivity [MD]) spanning the entire frontal and temporolimbic SWM, which were highly lateralized to the ipsilateral hemisphere. Conversely, reductions in cortical thickness in vMRI and alterations in the magnitude of the rs-fMRI response were less pronounced and less lateralized than the microstructural changes. Both stepwise regression and mediation analyses further revealed that FA and MD within SWM in LMT/PC regions were the most robust predictors of verbal memory, and that these associations were independent of left hippocampal volume. SIGNIFICANCE: These findings suggest that microstructural loss within the SWM is pronounced in patients with TLE, and injury to the SWM within the LMT/PC region plays a critical role in verbal memory impairment.

Indications and methodology for video-electroencephalographic studies in the epilepsy monitoring unit.

Although the epilepsy and neurology communities have position papers on a number of topics pertaining to epilepsy diagnosis and management, no current paper exists for the rationale and appropriate indications for epilepsy monitoring unit (EMU) evaluation. General neurologists, hospital administrators, and insurers also have yet to fully understand the role this type of testing has in the diagnosis and management of individuals with paroxysmal neurologic symptoms. This review outlines the indications for long-term video-electroencephalography (VEEG) for typical elective admissions to a specialized inpatient setting. The common techniques used in EMUs to obtain diagnostic information are reviewed. The added benefit of safety measures and clinical testing above that available for routine or long-term ambulatory electroencephalography is also discussed. The indications for admission to the EMU include differential diagnosis of paroxysmal spells, characterization of seizure types, presurgical epilepsy evaluations, seizure quantification, monitoring medication adjustment in a safe setting, and differentiation between seizures and side effects. We conclude that the appropriate use of this specialized testing can lead to an early and correct diagnosis in a variety of clinical circumstances. The EMU evaluation is considered the gold standard test for the definitive diagnosis of epilepsy and seizure-like spells.

Final safety, tolerability, and seizure outcomes in patients with focal epilepsy treated with adjunctive perampanel for up to 4 years in an open-label extension of phase III randomized trials: Study 307.

OBJECTIVE: To evaluate long-term safety/tolerability and seizure outcomes in patients with focal seizures treated with adjunctive perampanel in the open-label extension (OLEx) Study 307 (ClinicalTrials.gov identifier: NCT00735397). METHODS: Patients could enter the OLEx after completing one of the double-blind, phase III studies. Safety/tolerability and seizure outcomes (median percent reduction in seizure frequency per 28 days, and 50% responder and seizure freedom rates) were analyzed during the OLEx in cohorts with the same minimum perampanel exposure for all focal seizures and secondarily generalized seizures (SGS). An additional sensitivity analysis accounted for early dropouts from the OLEx. RESULTS: Of 1480 patients randomized across the double-blind studies, 1218 enrolled in the OLEx. The majority of patients (65.4%-80.9%) received a last daily dose of perampanel 12 mg and completed long-term assessment on the same, or one fewer, concomitant antiepileptic drug compared with baseline. The long-term safety/tolerability profile was consistent with the double-blind studies. Treatment-emergent adverse events (TEAEs) leading to discontinuation in >1% of patients were dizziness, irritability, and fatigue; TEAEs of clinical interest were stable for 4 years. In all cohorts, seizure outcome improvements were sustained over time. Median percent seizure reductions per 28 days reached 62.0% and 70.6% for patients with ≥3 (n = 436) or ≥4 (n = 78) years of exposure, respectively; corresponding 50% responder rates were 59.6% and 67.9%. The largest median percent seizure reduction per 28 days occurred in SGS for patients with SGS at baseline: 88.0% and 100.0% for patients with ≥3 (n = 190) or ≥4 (n = 28) years of exposure, respectively; in these cohorts 40.0% and 53.6% of patients, respectively, attained freedom from SGS. Median percent seizure reductions per 28 days were similar when early dropouts were accounted for. SIGNIFICANCE: Long-term (≤4 years) adjunctive perampanel treatment did not raise new safety/tolerability signals and was associated with markedly improved seizure control, particularly in patients with SGS at baseline.

Predictive models in the diagnosis and treatment of autoimmune epilepsy.

OBJECTIVE: To validate predictive models for neural antibody positivity and immunotherapy response in epilepsy. METHODS: We conducted a retrospective study of epilepsy cases at Mayo Clinic (Rochester-MN; Scottsdale-AZ, and Jacksonville-FL) in whom autoimmune encephalopathy/epilepsy/dementia autoantibody testing profiles were requested (06/30/2014-06/30/2016). An Antibody Prevalence in Epilepsy (APE) score, based on clinical characteristics, was assigned to each patient. Among patients who received immunotherapy, a Response to Immunotherapy in Epilepsy (RITE) score was assigned. Favorable seizure outcome was defined as >50% reduction of seizure frequency at the first follow-up. RESULTS: Serum and cerebrospinal fluid (CSF) from 1,736 patients were sent to the Mayo Clinic Neuroimmunology Laboratory for neural autoantibody evaluation. Three hundred eighty-seven of these patients met the diagnostic criteria for epilepsy. Central nervous system (CNS)-specific antibodies were detected in 44 patients. Certain clinical features such as new-onset epilepsy, autonomic dysfunction, viral prodrome, faciobrachial dystonic seizures/oral dyskinesia, inflammatory CSF profile, and mesial temporal magnetic resonance imaging (MRI) abnormalities had a significant association with positive antibody results. A significantly higher proportion of antibody-positive patients had an APE score ≥4 (97.7% vs. 21.6%, p < 0.01). Sensitivity and specificity of an APE score ≥4 to predict presence of specific neural auto-antibody were 97.7% and 77.9%, respectively. In the subset of patients who received immunotherapy (77), autonomic dysfunction, faciobrachial dystonic seizures/oral dyskinesia, early initiation of immunotherapy, and presence of antibodies targeting plasma membrane proteins (cell-surface antigens) were associated with favorable seizure outcome. Sensitivity and specificity of a RITE score ≥7 to predict favorable seizure outcome were 87.5% and 83.8%, respectively. SIGNIFICANCE: APE and RITE scores can aid diagnosis, treatment, and prognostication of autoimmune epilepsy. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Epilepsy treatment in adults and adolescents: Expert opinion, 2016.

INTRODUCTION: There are over twenty anti-seizure medications and anti-seizure devices available commercially in the United States. The multitude of treatment options for seizures can present a challenge to clinicians, especially those who are not subspecialists in the epilepsy field. Many clinical questions are not adequately answered in double-blind randomized controlled studies. In the presence of a knowledge gap, many clinicians consult a respected colleague with acknowledged expertise in the field. Our survey was designed to provide expert opinions on the treatment of epilepsy in adults and adolescents. METHOD: We surveyed a group of 42 physicians across the United States who are considered experts based on publication record in the field of epilepsy, or a leadership role in a National Association of Epilepsy Centers comprehensive epilepsy program. The survey consisted of 43 multiple-part patient scenario questions and was administered online using Redcap software. The experts provided their opinion on 1126 treatment options based on a modified Rand 9-point scale. The patient scenarios focused on genetically-mediated generalized epilepsy and focal epilepsy. The scenarios first focused on overall treatment strategy and then on specific pharmacotherapies. Other questions focused on treatment of specific patient populations (pregnancy, the elderly, patients with brain tumors, and post organ transplant patients), epilepsy patients with comorbidities (renal and hepatic disease, depression), and how to combine medications after failure of monotherapy. Statistical analysis of data used the expert consensus method. RESULTS: Valproate was considered a drug of choice in all genetically-mediated generalized epilepsies, except in the population of women of child-bearing age. Ethosuximide was a drug of choice in patient with absence seizures, and levetiracetam was a drug of choice in patients with genetic generalized tonic-clonic seizures and myoclonic seizures. Lamotrigine, levetiracetam and oxcarbazepine were considered drugs of choice for initial treatment of focal seizures. Lamotrigine and levetiracetam were the drugs of choice for women of child-bearing age with either genetic generalized epilepsy or focal epilepsy. Lamotrigine and levetiracetam were the drugs of choice in the elderly population. Lamotrigine was preferred in patients with co-morbid depression. Levetiracetam was the drug of choice in treating patients with hepatic failure, or who have undergone organ transplantation. Compared to the 2005 and 2001 surveys, there was increased preference for the use of levetiracetam and lamotrigine, and decreased preference for the use of phenytoin, gabapentin, phenobarbital and carbamazepine. DISCUSSION: The study presented here provides a "snapshot" of the clinical practices of experts in the treatment of epilepsy. The experts were very often in agreement, and reached consensus in 81% of the possible responses. However, expert opinion does not replace the medical literature; instead, it acts to supplement existing information. Using the study results is similar to requesting an expert consultation. Our findings suggest options that the clinician should consider to achieve best practice.

Perampanel for adjunctive treatment of partial-onset seizures: a pooled dose-response analysis of phase III studies.

OBJECTIVE: To better understand the relationship between efficacy and perampanel dose, integrated actual (last) dose data from three phase III trials and an extension study (blinded Conversion Period; open-label Maintenance Period) were analyzed. METHODS: Seizure frequency data were analyzed in patients who were randomized to and completed the 13-week Maintenance Period of the phase III studies on perampanel 8 mg, and who received an actual (last) dose of 12 mg during (1) the extension 16-week blinded Conversion Period or (2) weeks 1-13 of the extension Maintenance Period. Due to a treatment-by-region interaction (p = 0.042), analyses excluded patients from the Latin America region (n = 162/1,480; 10.9% of the treated cohort). RESULTS: Of 372 patients randomized to 8 mg in the phase III studies, 273 completed the Maintenance Period at 8 mg and 267 entered the extension study. In patients who then had an actual (last) dose of 12 mg during the extension blinded Conversion Period (n = 217), median percent change in seizure frequency per 28 days improved from -32.4% (8 mg, phase III Maintenance Period) to -44.2% (12 mg, extension blinded Conversion Period); 50% responder rates increased slightly from 37.3% to 42.9%. In patients who completed the phase III studies on 8 mg and had an actual (last) dose of 12 mg during weeks 1-13 of the extension Maintenance Period (n = 181), median percent change in seizure frequency per 28 days improved from -34.1% (phase III Maintenance Period) to -46.0% (weeks 1-13 extension Maintenance Period); 50% responder rates were 39.2% and 46.4%. Seizure control remained substantially unchanged in patients who completed the phase III studies at 12 mg and continued on that dose during the extension. SIGNIFICANCE: Increasing perampanel dose from 8 to 12 mg can produce additional benefits in seizure control in at least some patients who tolerate the higher dose.

Long-term safety of perampanel and seizure outcomes in refractory partial-onset seizures and secondarily generalized seizures: results from phase III extension study 307.

OBJECTIVE: To evaluate safety, tolerability, seizure frequency, and regional variations in treatment responses with the AMPA antagonist, perampanel, in a large extension study during up to 3 years of treatment. METHODS: Patients ≥ 12 years old with partial-onset seizures despite treatment with 1-3 antiepileptic drugs at baseline completed a perampanel phase III trial and entered extension study 307 (NCT00735397). Patients were titrated to 12 mg/day (or their individual maximum tolerated dose) during the blinded conversion period, followed by open-label maintenance. Exposure, safety (adverse events [AEs], vital signs, weight, electrocardiography [ECG], laboratory values) and seizure outcomes were analyzed; key measures were assessed by geographic regions. RESULTS: Among 1,216 patients, median exposure was 1.5 years (range 1 week to 3.3 years), with >300 patients treated for >2 years. Treatment retention was 58.5% at cutoff. AEs reported in ≥ 10% of patients were dizziness, somnolence, headache, fatigue, irritability, and weight increase. Only dizziness and irritability caused discontinuation in >1% of patients (3.9% and 1.3%, respectively). The only serious AEs reported in >1% of patients were epilepsy-related (convulsion, 3.0%; status epilepticus, 1.1%). No clinically relevant changes in vital signs, ECG or laboratory parameters were seen. After titration/conversion, responder rate and median percentage change from baseline in seizure frequency were stable: 46% for both measures at 9 months (in 980 patients with ≥ 9 months' exposure) and 58% and 60%, respectively, at 2 years (in the 337 patients with 2 years' exposure). Median percentage reduction in frequency of secondarily generalized (SG) seizures ranged from 77% at 9 months (N = 422) to 90% at 2 years (N = 141). Among the 694 patients with maintenance data ≥ 1 year, 5.3% were seizure-free for the entire year. SIGNIFICANCE: No new safety signals emerged during up to 3 years of perampanel exposure in 39 countries. Seizure responses remained stable, with marked reductions, particularly in SG seizures.

Acoustic and language-specific sources for phonemic abstraction from speech.

Spoken language comprehension requires abstraction of linguistic information from speech, but the interaction between auditory and linguistic processing of speech remains poorly understood. Here, we investigate the nature of this abstraction using neural responses recorded intracranially while participants listened to conversational English speech. Capitalizing on multiple, language-specific patterns where phonological and acoustic information diverge, we demonstrate the causal efficacy of the phoneme as a unit of analysis and dissociate the unique contributions of phonemic and spectrographic information to neural responses. Quantitive higher-order response models also reveal that unique contributions of phonological information are carried in the covariance structure of the stimulus-response relationship. This suggests that linguistic abstraction is shaped by neurobiological mechanisms that involve integration across multiple spectro-temporal features and prior phonological information. These results link speech acoustics to phonology and morphosyntax, substantiating predictions about abstractness in linguistic theory and providing evidence for the acoustic features that support that abstraction.

Validity of the MoCA as a cognitive screening tool in epilepsy: Are there implications for global care and research?

OBJECTIVE: This study evaluated the diagnostic performance of a widely available cognitive screener, the Montreal cognitive assessment (MoCA), to detect cognitive impairment in older patients (age ≥ 55) with epilepsy residing in the US, using the International Classification of Cognitive Disorders in Epilepsy (IC-CoDE) as the gold standard. METHODS: Fifty older adults with focal epilepsy completed the MoCA and neuropsychological measures of memory, language, executive function, and processing speed/attention. The IC-CoDE taxonomy divided participants into IC-CoDE Impaired and Intact groups. Sensitivity and specificity across several MoCA cutoffs were examined. Spearman correlations examined relationships between the MoCA total score and clinical and demographic variables and MoCA domain scores and individual neuropsychological tests. RESULTS: IC-CoDE impaired patients demonstrated significantly lower scores on the MoCA total, visuospatial/executive, naming, language, delayed recall, and orientation domain scores (Cohen's d range: 0.336-2.77). The recommended MoCA cutoff score < 26 had an overall accuracy of 72%, 88.2% sensitivity, and 63.6% specificity. A MoCA cutoff score < 24 yielded optimal sensitivity (70.6%) and specificity (78.8%), with overall accuracy of 76%. Higher MoCA total scores were associated with greater years of education (p = 0.016) and fewer antiseizure medications (p = 0.049). The MoCA memory domain was associated with several standardized measures of memory, MoCA language domain with category fluency, and MoCA abstraction domain with letter fluency. SIGNIFICANCE: This study provides initial validation of the MoCA as a useful screening tool for older adults with epilepsy that can be used to identify patients who may benefit from comprehensive neuropsychological testing. Further, we demonstrate that a lower cutoff (i.e., <24) better captures cognitive impairment in older adults with epilepsy than the generally recommended cutoff and provides evidence for construct overlap between MoCA domains and standard neuropsychological tests. Critically, similar efforts in other regions of the world are needed. PLAIN LANGUAGE SUMMARY: The Montreal cognitive assessment (MoCA) can be a helpful tool to screen for cognitive impairment in older adults with epilepsy. We recommend that adults 55 or older with epilepsy who score less than 24 on the MoCA are referred to a neuropsychologist for a comprehensive evaluation to assess any changes in cognitive abilities and mood.

Perampanel, a selective, noncompetitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist, as adjunctive therapy for refractory partial-onset seizures: interim results from phase III, extension study 307.

PURPOSE: To evaluate safety, tolerability, and seizure outcome data during long-term treatment with once-daily adjunctive perampanel (up to 12 mg/day) in patients with refractory partial-onset seizures. METHODS: Study 307 was an extension study for patients completing the double-blind phase of three pivotal phase III trials (studies 304, 305, and 306). The study consisted of two phases: an open-label treatment phase (including a 16-week blinded conversion period and a planned 256-week maintenance period) and a 4-week follow-up phase. Patients were blindly titrated during the conversion period to their individual maximum tolerated dose (maximum 12 mg/day). Adverse events (AEs) were monitored throughout the study and seizure frequency recorded. The interim data cutoff date for analyses was December 1, 2010. KEY FINDINGS: In total, 1,218 patients were enrolled in the study. At the interim cutoff date, 1,186 patients were in the safety analysis set; 1,089 (91.8%) patients had >16 weeks of exposure to perampanel, 580 (48.9%) patients had >1 year of exposure, and 19 (1.6%) patients had >2 years of exposure. At the interim analysis, 840 (70.8%) patients remained on perampanel treatment. The large majority of patients (n = 1,084 [91%]) were titrated to 10 mg or 12 mg/day. Median (range) duration of exposure was 51.4 (1.1-128.1) weeks. Treatment-emergent AEs were reported in 87.4% of patients. The most frequent were dizziness (43.9%), somnolence (20.2%), headache (16.7%), and fatigue (12.1%). Serious AEs were reported in 13.2% of patients. In the intent-to-treat analysis set (n = 1,207), the frequency of all seizures decreased over the first 26 weeks of perampanel treatment in patients with at least 26 weeks of exposure to perampanel (n = 1,006 [83.3%]); this reduction was maintained in patients with at least 1 year of exposure (n = 588 [48.7%]). The overall median percent changes in seizure frequency in patients included in each 13-week interval of perampanel treatment were -39.2% for weeks 14-26 (n = 1,114), -46.5% for weeks 40-52 (n = 731), and -58.1% for weeks 92-104 (n = 59). Overall responder rates in patients included in each 13-week interval of perampanel treatment were 41.4% for weeks 14-26 (n = 1,114), 46.9% for weeks 40-52 (n = 731), and 62.7% for weeks 92-104 (n = 59). During the blinded conversion period, the reduction in seizure frequency in patients previously randomized to placebo (-42.4%, n = 369) was similar to that in patients previously randomized to perampanel (-41.5%, n = 817). SIGNIFICANCE: Consistent with pivotal phase III trials, these interim results demonstrated that perampanel had a favorable tolerability profile in patients with refractory partial-onset seizures over the longer term. The decrease in seizure frequency was consistent and maintained in those patients over at least 1 year of perampanel exposure.

The epilepsy phenome/genome project.

BACKGROUND: Epilepsy is a common neurological disorder that affects approximately 50 million people worldwide. Both risk of epilepsy and response to treatment partly depend on genetic factors, and gene identification is a promising approach to target new prediction, treatment, and prevention strategies. However, despite significant progress in the identification of genes causing epilepsy in families with a Mendelian inheritance pattern, there is relatively little known about the genetic factors responsible for common forms of epilepsy and so-called epileptic encephalopathies. Study design The Epilepsy Phenome/Genome Project (EPGP) is a multi-institutional, retrospective phenotype-genotype study designed to gather and analyze detailed phenotypic information and DNA samples on 5250 participants, including probands with specific forms of epilepsy and, in a subset, parents of probands who do not have epilepsy. RESULTS: EPGP is being executed in four phases: study initiation, pilot, study expansion/establishment, and close-out. This article discusses a number of key challenges and solutions encountered during the first three phases of the project, including those related to (1) study initiation and management, (2) recruitment and phenotyping, and (3) data validation. The study has now enrolled 4223 participants. CONCLUSIONS: EPGP has demonstrated the value of organizing a large network into cores with specific roles, managed by a strong Administrative Core that utilizes frequent communication and a collaborative model with tools such as study timelines and performance-payment models. The study also highlights the critical importance of an effective informatics system, highly structured recruitment methods, and expert data review.

Bilingualism and Structural Network Organization in Temporal Lobe Epilepsy: Resilience in Neurologic Disease.

BACKGROUND AND OBJECTIVES: There is growing evidence that bilingualism can induce neuroplasticity and modulate neural efficiency, resulting in greater resistance to neurologic disease. However, whether bilingualism is beneficial to neural health in the presence of epilepsy is unknown. We tested whether bilingual individuals with temporal lobe epilepsy (TLE) have improved whole-brain structural white matter network organization. METHODS: Healthy controls and individuals with TLE recruited from 2 specialized epilepsy centers completed diffusion-weighted MRI and neuropsychological testing as part of an observational cohort study. Whole-brain connectomes were generated via diffusion tractography and analyzed using graph theory. Global analyses compared network integration (path length) and specialization (transitivity) in TLE vs controls and in a 2 (left vs right TLE) × 2 (bilingual vs monolingual) model. Local analyses compared mean local efficiency of predefined frontal-executive and language (i.e., perisylvian) subnetworks. Exploratory correlations examined associations between network organization and neuropsychological performance. RESULTS: A total of 29 bilingual and 88 monolingual individuals with TLE matched on several demographic and clinical variables and 81 age-matched healthy controls were included. Globally, a significant interaction between language status and side of seizure onset revealed higher network organization in bilinguals compared with monolinguals but only in left TLE (LTLE). Locally, bilinguals with LTLE showed higher efficiency in frontal-executive but not in perisylvian networks compared with LTLE monolinguals. Improved whole-brain network organization was associated with better executive function performance in bilingual but not monolingual LTLE. DISCUSSION: Higher white matter network organization in bilingual individuals with LTLE suggests a neuromodulatory effect of bilingualism on whole-brain connectivity in epilepsy, providing evidence for neural reserve. This may reflect attenuation of or compensation for epilepsy-related dysfunction of the left hemisphere, potentially driven by increased efficiency of frontal-executive networks that mediate dual-language control. This highlights a potential role of bilingualism as a protective factor in epilepsy, motivating further research across neurologic disorders to define mechanisms and develop interventions.

Preoperative white matter network organization and memory decline after epilepsy surgery.

OBJECTIVE: Risk for memory decline is a common concern for individuals with temporal lobe epilepsy (TLE) undergoing surgery. Global and local network abnormalities are well documented in TLE. However, it is less known whether network abnormalities predict postsurgical memory decline. The authors examined the role of preoperative global and local white matter network organization and risk of postoperative memory decline in TLE. METHODS: One hundred one individuals with TLE (n = 51 with left TLE and 50 with right TLE) underwent preoperative T1-weighted MRI, diffusion MRI, and neuropsychological memory testing in a prospective longitudinal study. Fifty-six age- and sex-matched controls completed the same protocol. Forty-four patients (22 with left TLE and 22 with right TLE) subsequently underwent temporal lobe surgery and postoperative memory testing. Preoperative structural connectomes were generated via diffusion tractography and analyzed using measures of global and local (i.e., medial temporal lobe [MTL]) network organization. Global metrics measured network integration and specialization. The local metric was calculated as an asymmetry of the mean local efficiency between the ipsilateral and contralateral MTLs (i.e., MTL network asymmetry). RESULTS: Higher preoperative global network integration and specialization were associated with higher preoperative verbal memory function in patients with left TLE. Higher preoperative global network integration and specialization, as well as greater leftward MTL network asymmetry, predicted greater postoperative verbal memory decline for patients with left TLE. No significant effects were observed in right TLE. Accounting for preoperative memory score and hippocampal volume asymmetry, MTL network asymmetry uniquely explained 25%-33% of the variance in verbal memory decline for left TLE and outperformed hippocampal volume asymmetry and global network metrics. MTL network asymmetry alone produced good diagnostic classification of memory decline in left TLE (i.e., an area under the receiver operating characteristic curve of 0.80-0.84 and correct classification of 65%-76% of cases with cross-validation). CONCLUSIONS: These preliminary data suggest that global white matter network disruption contributes to verbal memory impairment preoperatively and predicts postsurgical verbal memory outcomes in left TLE. However, a leftward asymmetry of MTL white matter network organization may confer the highest risk for verbal memory decline. Although this requires replication in a larger sample, the authors demonstrate the importance of characterizing preoperative local white matter network properties within the to-be-operated hemisphere and the reserve capacity of the contralateral MTL network, which may eventually be useful in presurgical planning.

An Interpretable Deep Learning Model for Speech Activity Detection Using Electrocorticographic Signals.

Numerous state-of-the-art solutions for neural speech decoding and synthesis incorporate deep learning into the processing pipeline. These models are typically opaque and can require significant computational resources for training and execution. A deep learning architecture is presented that learns input bandpass filters that capture task-relevant spectral features directly from data. Incorporating such explainable feature extraction into the model furthers the goal of creating end-to-end architectures that enable automated subject-specific parameter tuning while yielding an interpretable result. The model is implemented using intracranial brain data collected during a speech task. Using raw, unprocessed timesamples, the model detects the presence of speech at every timesample in a causal manner, suitable for online application. Model performance is comparable or superior to existing approaches that require substantial signal preprocessing and the learned frequency bands were found to converge to ranges that are supported by previous studies.