The neural activity of auditory conscious perception.

Although recent work has made headway in understanding the neural temporospatial dynamics of conscious perception, much of that work has focused on visual paradigms. To determine whether there are shared mechanisms for perceptual consciousness across sensory modalities, here we test within the auditory domain. Participants completed an auditory threshold task while undergoing intracranial electroencephalography.

Epilepsy surgery education and practice around the globe: An ILAE taskforce report.

Up to 80% of the world's population with epilepsy lives in low and middle-income countries. Around one-third of these patients will have drug-resistant epilepsy, for which epilepsy surgery is an option. Unfortunately, many of these regions, as well as some more developed nations, lack sufficient epilepsy surgery units and trained neurosurgeons.

The human claustrum tracks slow waves during sleep.

Slow waves are a distinguishing feature of non-rapid-eye-movement (NREM) sleep, an evolutionarily conserved process critical for brain function. Non-human studies suggest that the claustrum, a small subcortical nucleus, coordinates slow waves. We show that, in contrast to neurons from other brain regions, claustrum neurons in the human brain increase their spiking activity and track slow waves during NREM sleep, suggesting that the claustrum plays a role in coordinating human sleep architecture.

Combined neuromodulation and resection for functional cortex epilepsy: a case series.

Objective: Medically refractory epilepsy (MRE) often requires resection of the seizure onset zone (SOZ) for effective treatment. However, when the SOZ is in functional cortex (FC), achieving complete and safe resection becomes difficult, due to the seizure network overlap with function. The authors aimed to assess the safety and outcomes of a combined approach involving partial resection combined with focal neuromodulation for FC refractory epilepsy.

Systematic 1 Hz direct electrical stimulation for seizure induction: A reliable method for localizing seizure onset zone and predicting seizure freedom.

Objective: To prospectively investigate the utility of seizure induction using systematic 1 Hz stimulation by exploring its concordance with the spontaneous seizure onset zone (SOZ) and relation to surgical outcome; comparison with seizures induced by non-systematic 50 Hz stimulation was attempted as well.

Methods: Prospective cohort study from 2018 to 2021 with ≥ 1 y post-surgery follow up at Yale New Haven Hospital. With 1 Hz, all or most of the gray matter contacts were stimulated at 1, 5, and 10 mA for 30-60s.

The human claustrum tracks slow waves during sleep.

Slow waves are a distinguishing feature of non-rapid-eye-movement (NREM) sleep, an evolutionarily conserved process critical for brain function. Non-human studies posit that the claustrum, a small subcortical nucleus, coordinates slow waves. We recorded claustrum neurons in humans during sleep.

Statistical learning in epilepsy: Behavioral and anatomical mechanisms in the human brain.

Objective: Statistical learning, the fundamental cognitive ability of humans to extract regularities across experiences over time, engages the medial temporal lobe (MTL) in the healthy brain. This leads to the hypothesis that statistical learning (SL) may be impaired in patients with epilepsy (PWE) involving the temporal lobe, and that this impairment could contribute to their varied memory deficits. In turn, studies done in collaboration with PWE, that evaluate the necessity of MTL circuitry through disease and causal perturbations, provide an opportunity to advance basic understanding of SL.

Responsive neurostimulation as a treatment for super-refractory focal status epilepticus: a systematic review and case series.

Objective: Super-refractory status epilepticus (SRSE) has high rates of morbidity and mortality. Few published studies have investigated neurostimulation treatment options in the setting of SRSE. This systematic literature review and series of 10 cases investigated the safety and efficacy of implanting and activating the responsive neurostimulation (RNS) system acutely during SRSE and discusses the rationale for lead placement and selection of stimulation parameters.

Statistical learning in epilepsy: Behavioral, anatomical, and causal mechanisms in the human brain.

Statistical learning, the fundamental cognitive ability of humans to extract regularities across experiences over time, engages the medial temporal lobe in the healthy brain. This leads to the hypothesis that statistical learning may be impaired in epilepsy patients, and that this impairment could contribute to their varied memory deficits. In turn, epilepsy patients provide a platform to advance basic understanding of statistical learning by helping to evaluate the necessity of medial temporal lobe circuitry through disease and causal perturbations.

Contribution of Somatic Ras/Raf/Mitogen-Activated Protein Kinase Variants in the Hippocampus in Drug-Resistant Mesial Temporal Lobe Epilepsy.

Importance: Mesial temporal lobe epilepsy (MTLE) is the most common focal epilepsy subtype and is often refractory to antiseizure medications. While most patients with MTLE do not have pathogenic germline genetic variants, the contribution of postzygotic (ie, somatic) variants in the brain is unknown.

Objective: To test the association between pathogenic somatic variants in the hippocampus and MTLE.

TREM2 and APOE do not modulate phagocytic clearance of dying cells in the live mammalian brain.

TREM2 and APOE are two major risk factors for Alzheimer's disease (AD) that have been proposed to play crucial roles in microglia pathophysiology by affecting their ability to phagocytose cellular debris or aggregated proteins. In this study, we investigated for the first time the impact of TREM2 and APOE on the removal of dying neurons in the live brain by implementing a targeted photochemical method for programmed cell death induction combined with high-resolution two-photon imaging. Our findings showed that the deletion of either TREM2 or APOE did not affect the dynamics of microglia engagement with dying neurons or their efficiency in phagocytosing corpses.

Recent advances in epilepsy surgery.

Purpose Of Review: Technological innovations in the preoperative evaluation, surgical techniques and outcome prediction in epilepsy surgery have grown exponentially over the last decade. This review highlights and emphasizes relevant updates in techniques and diagnostic tools, discussing their context within standard practice at comprehensive epilepsy centres.

Recent Findings: High-resolution structural imaging has set an unprecedented opportunity to detect previously unrecognized subtle abnormalities.

Transfrontal Approach to the Amygdala for Ablation With Laser Interstitial Thermal Therapy: An Epilepsy Case Report.

Background And Importance: Stereotactic laser amygdalohippocampotomy (SLAH) using laser interstitial thermal therapy is a minimally invasive surgery used to treat mesial temporal lobe epilepsy. It uses laser probes inserted through occipital and temporo-occipital trajectories to ablate the hippocampus and amygdala. However, these trajectories are limited in their ability to ablate the superior amygdala and entorhinal cortex (ERC).

Temporal Dynamics of Competition between Statistical Learning and Episodic Memory in Intracranial Recordings of Human Visual Cortex.

The function of long-term memory is not just to reminisce about the past, but also to make predictions that help us behave appropriately and efficiently in the future. This predictive function of memory provides a new perspective on the classic question from memory research of why we remember some things but not others. If prediction is a key outcome of memory, then the extent to which an item generates a prediction signifies that this information already exists in memory and need not be encoded.

Remembering the pattern: A longitudinal case study on statistical learning in spatial navigation and memory consolidation.

Distinct brain systems are thought to support statistical learning over different timescales. Regularities encountered during online perceptual experience can be acquired rapidly by the hippocampus. Further processing during offline consolidation can establish these regularities gradually in cortical regions, including the medial prefrontal cortex (mPFC).

Child Neurology: Functional Reorganization Mediating Supplementary Motor Area Syndrome Recovery in Agenesis of the Corpus Callosum.

Supplementary motor area (SMA) syndrome is a typically transient condition resulting from damage to the medial premotor cortex. The exact mechanism of recovery remains unknown but is traditionally described as a process involving functional compensation by the contralateral SMA through corpus callosal fibers. The purpose of this case study is to highlight a distinct extracallosal mechanism of functional recovery from an SMA syndrome in a patient with agenesis of the corpus callosum (ACC).

Factors Predicting Outcome After Intracranial EEG Evaluation in Patients With Medically Refractory Epilepsy.

Background And Objectives: The aim of this study was to identify predictors of a resective surgery and subsequent seizure freedom following intracranial EEG (ICEEG) for seizure-onset localization.

Methods: This is a retrospective chart review of 178 consecutive patients with medically refractory epilepsy who underwent ICEEG monitoring from 2002 to 2015. Univariable and multivariable regression analysis identified independent predictors of resection vs other options.

Optimizing the surgical management of MRI-negative epilepsy in the neuromodulation era.

Objective: To evaluate the role of intracranial electroencephalography monitoring in diagnosing and directing the appropriate therapy for MRI-negative epilepsy and to present the surgical outcomes of patients following treatment.

Methods: Retrospective chart review between 2015-2021 at a single institution identified 48 patients with no lesion on MRI, who received surgical intervention for their epilepsy. The outcomes assessed were the surgical treatment performed and the International League Against Epilepsy seizure outcomes at 1 year of follow-up.

Management of patients with medically intractable epilepsy and anterior temporal lobe encephaloceles.

Objective: Temporal lobe encephaloceles (TLENs) are a significant cause of medically refractory epilepsy, but there is little consensus regarding their workup and treatment. This study characterizes these lesions and their role in seizures and aims to standardize preoperative evaluation and surgical management.

Methods: Patients with TLEN who had undergone resective epilepsy surgery from December 2015 to August 2020 at a single institution were included in the study.

Increased branched-chain amino acids at baseline and hours before a spontaneous seizure in the human epileptic brain.

The objective of this study was to monitor the extracellular brain chemistry dynamics at baseline and in relation to spontaneous seizures in human patients with refractory epilepsy. Thirty patients with drug-resistant focal epilepsy underwent intracranial electroencephalography and concurrent brain microdialysis for up to 8 continuous days. Extracellular brain glutamate, glutamine, and the branched-chain amino acids (BCAAs) valine, leucine, and isoleucine were quantified in the dialysis samples by liquid chromatography-tandem mass spectrometry.

Depth Electrode Guided Anterior Insulectomy: 2-Dimensional Operative Video.

The insula is well established as an epileptogenic area.1 Insular epilepsy surgery demands precise anatomic knowledge2-4 and tailored removal of the epileptic zone with careful neuromonitoring.5 We present an operative video illustrating an intracranial electroencephalogram (EEG) depth electrode guided anterior insulectomy.

Case Report: Suprasellar Pituitary Adenoma Presenting With Temporal Lobe Seizures.

Seizures in patients with pituitary pathology are uncommon and typically secondary to electrolyte disturbances. Rarely, seizures have been described from mass effect related to large prolactinomas undergoing medical treatment. We describe a 54 year-old male who presented with a first-time generalized seizure, secondary to a pituitary macroadenoma compressing the left temporal lobe.