Despite long knowing what brain areas support language comprehension, our knowledge of the neural computations that these frontal and temporal regions implement remains limited. One important unresolved question concerns functional differences among the neural populations that comprise the language network. Here we leveraged the high spatiotemporal resolution of human intracranial recordings (n = 22) to examine responses to sentences and linguistically degraded conditions.
View Article and Find Full Text PDFDecision-makers objectively commit to a definitive choice, yet at the subjective level, human decisions appear to be associated with a degree of uncertainty. Whether decisions are definitive (i.e.
View Article and Find Full Text PDFDrug-resistant epilepsy is associated with reduced quality of life (QoL) due to a myriad of disease-related and psychosocial factors. Although consciousness during seizures is a core feature of seizure classification, its impact on QoL in people with epilepsy (PWE) is not well understood. This study aimed to address this gap by comparing QoL between PWE with focal aware (FA) versus impaired awareness (FIA) seizures.
View Article and Find Full Text PDFBackground And Objectives: Cenobamate (CNB) is a United States Food and Drug Administration-approved antiseizure medication (ASM) for focal-onset seizures; however, its potential clinical effectiveness as a broad-spectrum ASM is not established. CNB has a proposed dual mechanism of action with preferential blockade of persistent sodium currents and positive allosteric modulation of the γ-aminobutyric acid-A (GABA-A) receptor. We evaluated the efficacy of CNB in drug refractory patients with genetic generalized epilepsies (GGE) or combined generalized and focal epilepsies (CGFE), including developmental and epileptic encephalopathies.
View Article and Find Full Text PDFObjective: To investigate the feasibility of passive functional mapping in the receptive language cortex during general anesthesia using electrocorticographic (ECoG) signals.
Methods: We used subdurally placed ECoG grids to record cortical responses to speech stimuli during awake and anesthesia conditions. We identified the cortical areas with significant responses to the stimuli using the spectro-temporal consistency of the brain signal in the broadband gamma (BBG) frequency band (70-170 Hz).
Objective: Magnetic resonance-guided laser interstitial thermal therapy (MRLiTT) for treating temporal lobe epilepsy has recently gained popularity. We aimed to investigate the predictive value of pre-and post-MRLiTT epileptiform discharges (EDs) on intraoperative electrocorticography (iECoG) in seizure outcomes for patients with mesial temporal lobe epilepsy (mTLE).
Methods: We conducted a pilot, prospective single-center cohort study on seven consecutive patients with mTLE that underwent MRLiTT.
How is music represented in the brain? While neuroimaging has revealed some spatial segregation between responses to music versus other sounds, little is known about the neural code for music itself. To address this question, we developed a method to infer canonical response components of human auditory cortex using intracranial responses to natural sounds, and further used the superior coverage of fMRI to map their spatial distribution. The inferred components replicated many prior findings, including distinct neural selectivity for speech and music, but also revealed a novel component that responded nearly exclusively to music with singing.
View Article and Find Full Text PDFBackground: Deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) is an increasingly utilized treatment of drug-resistant epilepsy. To date, the effect of high-frequency stimulation (HFS) vs low-frequency stimulation (LFS) in ANT DBS is poorly understood.
Objective: To assess differences in the acute effect of LFS vs HFS in ANT DBS utilizing blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI).
Background And Purpose: Deep brain stimulation of the thalamus is an effective treatment for multiple neurological disorders. The centromedian and parafascicular nuclei are recently emerging targets for multiple conditions, such as epilepsy and Tourette syndrome; however, their limited visibility on conventional magnetic resonance imaging sequences has been a major obstacle. The goal of this study was to demonstrate the feasibility of a high-resolution and high-contrast targeting sequence for centromedian-parafascicular deep brain stimulation using a recently described magnetic resonance imaging sequence, three-dimensional edge-enhancing gradient echo.
View Article and Find Full Text PDFEpileptogenic encephaloceles, most frequently located in the temporal lobe, are a known lesional cause of focal epilepsy. Data are limited regarding diagnosis, management, and outcomes of patients with epilepsy in the setting of an encephalocele, because the literature mostly comprises case reports, case series, and retrospective studies. We conducted a broad literature review for articles related to encephaloceles and epilepsy regardless of level of evidence.
View Article and Find Full Text PDFBackground: The pathogenesis of glioma-related seizures (GRS) is poorly understood. Here in, we aim to identify putative molecular pathways that lead to the development of GRS.
Methods: We determined brain transcriptome from intraoperative human brain tissue of patients with either GRS, glioma without seizures (non-GRS), or with idiopathic temporal lobe epilepsy (iTLE).
The objective of this study was to describe serological association of musicogenic epilepsy and to evaluate clinical features and outcomes of seropositive cases. Through retrospective chart review, musicogenic epilepsy patients were identified. Among 16 musicogenic epilepsy patients, nine underwent autoantibody evaluations and all had high-titer glutamic acid decarboxylase 65-immunoglobulin G (GAD65-IgG; >20 nmol·L , serum, normal ≤ .
View Article and Find Full Text PDFStereo-EEG (sEEG) is an invasive recording technique used to localize the seizure-onset zone for epilepsy surgery in people with drug-resistant focal seizures. Pathological crying reflects disordered emotional expression and the anterior insula is known to play a role in empathy and socio-emotional processing. We describe a patient where electrical stimulation mapping (ESM) of the anterior insula during sEEG generated pathological crying and profound sadness that was time-locked to the electrical stimulus.
View Article and Find Full Text PDFEpilepsy Behav
February 2021
Objective: We aimed to examine the impact of resumption of home antiseizure drugs alone (ASD-) compared with adjunct administration of scheduled intravenous (IV) lorazepam 2 mg every 6 h (ASD+) following ictal single-photon emission computed tomography (SPECT) injection on the localization value of SPECT studies and treatment-emergent adverse events (TEAEs).
Methods: We conducted a prospective study at Mayo Clinic inpatient epilepsy monitoring unit (EMU) between January 2018 and May 2020 in Jacksonville, Florida. The ASD- and ASD+ groups were compared for concordance of SPECT studies with the epilepsy surgical conference (ESC) consensus or intracranial electroencephalography (icEEG) findings as reference.
Introduction: 20.8% of the United States population and 67% of the European population speak two or more languages. Intraoperative different languages, mapping, and localization are crucial.
View Article and Find Full Text PDFFunctional imaging studies have implicated an area in the left lateral fusiform gyrus, known as the visual word form area (VWFA), in pre-lexical orthographic processing. There are very few studies that have examined the functional specificity of this area in patients with discrete lesions limited to this region. Here we describe a rare opportunity to examine the functional specificity of the VWFA in a patient with stereo EEG (sEEG) electrodes implanted for localization of seizures prior to epilepsy surgery.
View Article and Find Full Text PDFTilt table testing is a common noninvasive diagnostic test performed to reproduce and evaluate syncope in a vulnerable patient and subsequently guide therapy. Electroencephalography (EEG) is typically useful for identifying interictal and ictal abnormalities within the context of epilepsy or suspected epilepsy. We report a series of patients who underwent simultaneous tilt table testing with EEG.
View Article and Find Full Text PDFObjective: To evaluate intraoperative use of a novel high-density circular grid in detecting after-discharges (AD) on electrocorticography (ECoG) during functional brain mapping (FBM).
Methods: FBM during glioma surgery (10/2016 to 5/2019) recorded ADs using a 22-channel circular grid compared to conventional strip electrodes. ADs were analyzed for detection, duration, amplitude, morphology, histology, direction, and clinical signs.
Epilepsy Behav Rep
January 2020
This paper reports the electroclinical manifestations of an epilepsy syndrome associated with a chromodomain helicase DNA-binding protein 2 (CHD2) gene mutation with clinical semiology and electroencephalographic (EEG) features consistent with juvenile myoclonic epilepsy (JME). Myoclonic and myoclonic-tonic-clonic seizures, as well as generalized 4- to 5-Hz high-amplitude spike-wave and polyspike-wave discharges, were well characterized in an adolescent. However, the atypical age of onset, developmental disability, and apparent drug resistance led to suspicion of an alternative etiology for epilepsy, subsequently verified as a CHD2 gene mutation.
View Article and Find Full Text PDFBackground: Electrical stimulation of the cortex using subdurally implanted electrodes can causally reveal structural connectivity by eliciting cortico-cortical evoked potentials (CCEPs). While many studies have demonstrated the potential value of CCEPs, the methods to evaluate them were often relatively subjective, did not consider potential artifacts, and did not lend themselves to systematic scientific investigations.
New Method: We developed an automated and quantitative method called SIGNI (Stimulation-Induced Gamma-based Network Identification) to evaluate cortical population-level responses to electrical stimulation that minimizes the impact of electrical artifacts.
J Clin Neurophysiol
March 2018
The application of electrical stimulation mapping (ESM) of the brain for clinical use is approximating a century. Despite this long-standing history, the value of ESM for guiding surgical resections and sparing eloquent cortex is documented largely by small retrospective studies, and ESM protocols are largely inherited and lack standardization. Although models are imperfect and mechanisms are complex, the probabilistic causality of ESM has guaranteed its perpetuation into the 21st century.
View Article and Find Full Text PDFMicroglia are well known to play a critical role in maintaining brain homeostasis. However, their role in epileptogenesis has yet to be determined. Here, we demonstrate that elevated mTOR signaling in mouse microglia leads to phenotypic changes, including an amoeboid-like morphology, increased proliferation, and robust phagocytosis activity, but without a significant induction of pro-inflammatory cytokines.
View Article and Find Full Text PDFAim: Childhood absence epilepsy (CAE) and benign childhood epilepsy with centrotemporal spikes (BECTS) are the most common forms of childhood epilepsy. Recent studies in animal models suggest that the two phenotypes may represent a neurobiological continuum. Although the coexistence of CAE and BECTS has been reported, this issue remains controversial.
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