Unravelling the origin of reward positivity: a human intracranial event-related brain potential study.

Reward positivity (RewP) is an event-related brain potential component that emerges ∼250-350 ms after receiving reward-related feedback stimuli and is believed to be important for reinforcement learning and reward processing. Although numerous localization studies have indicated that the anterior cingulate cortex (ACC) is the neural generator of this component, other studies have identified sources outside of the ACC, fuelling a debate about its origin. Because the results of EEG and magnetoencephalography source-localization studies are severely limited by the inverse problem, we addressed this question by leveraging the high spatial and temporal resolution of intracranial EEG.

Current state of the art of traditional and minimal invasive epilepsy surgery approaches.

Introduction: Open resective surgery remains the main treatment modality for refractory epilepsy, but is often considered a last resort option due to its invasiveness.

Research Question: This manuscript aims to provide an overview on traditional as well as minimally invasive surgical approaches in modern state of the art epilepsy surgery.

Materials And Methods: This narrative review addresses both historical and contemporary as well as minimal invasive surgical approaches in epilepsy surgery.

Deep Brain Stimulation of the Anterior Nucleus of the Thalamus in Drug-Resistant Epilepsy in the MORE Multicenter Patient Registry.

Background And Objectives: The efficacy of deep brain stimulation of the anterior nucleus of the thalamus (ANT DBS) in patients with drug-resistant epilepsy (DRE) was demonstrated in the double-blind Stimulation of the Anterior Nucleus of the Thalamus for Epilepsy randomized controlled trial. The Medtronic Registry for Epilepsy (MORE) aims to understand the safety and longer-term effectiveness of ANT DBS therapy in routine clinical practice.

Methods: MORE is an observational registry collecting prospective and retrospective clinical data.

Cognitive tasks propagate the neural entrainment in response to a visual 40 Hz stimulation in humans.

Introduction: Alzheimer's disease is one of the great challenges in the coming decades, and despite great efforts, a widely effective disease-modifying therapy in humans remains elusive. One particular promising non-pharmacological therapy that has received increased attention in recent years is based on the Gamma ENtrainment Using Sensory stimulation (GENUS), a high-frequency neural response elicited by a visual and/or auditory stimulus at 40 Hz. While this has shown to be effective in animal models, studies on human participants have reported varying success.

MRI-Compatible and Conformal Electrocorticography Grids for Translational Research.

Intraoperative electrocorticography (ECoG) captures neural information from the surface of the cerebral cortex during surgeries such as resections for intractable epilepsy and tumors. Current clinical ECoG grids come in evenly spaced, millimeter-sized electrodes embedded in silicone rubber. Their mechanical rigidity and fixed electrode spatial resolution are common shortcomings reported by the surgical teams.

Survival impact of incidental subventricular zone irradiation in IDH-wildtype glioblastoma.

Background And Purpose: The subventricular zone (SVZ) is an important niche for neural stem cells but probably also for brain tumor propagating cells, including the glioblastoma stem cell. The SVZ may become a target for radiation therapy in glioblastoma patients. However, reports studying the effect of irradiation of the SVZ on glioblastoma patient survival show conflicting results.

Partial resection offers an overall survival benefit over biopsy in MGMT-unmethylated IDH-wildtype glioblastoma patients.

Background Isocitrate dehydrogenase (IDH)-wildtype glioblastoma patients with O-methylguanine-DNA-methyltransferase (MGMT)-unmethylated tumors have the worst outcome of all glioblastoma patients. The overall survival (OS) benefit of partial resection of glioblastoma compared to biopsy only remains controversial specifically in relation to molecular factors. In this report, we analyzed the effect of incomplete resection on OS compared to biopsy only in a cohort of IDH-wildtype glioblastoma patients who were uniformly treated with temozolomide-based chemoradiotherapy (TMZ-CR) after surgery.

Localization of deep brain activity with scalp and subdural EEG.

To what extent electrocorticography (ECoG) and electroencephalography (scalp EEG) differ in their capability to locate sources of deep brain activity is far from evident. Compared to EEG, the spatial resolution and signal-to-noise ratio of ECoG is superior but its spatial coverage is more restricted, as is arguably the volume of tissue activity effectively measured from. Moreover, scalp EEG studies are providing evidence of locating activity from deep sources such as the hippocampus using high-density setups during quiet wakefulness.

High-gamma oscillations precede visual steady-state responses: A human electrocorticography study.

The robust steady-state cortical activation elicited by flickering visual stimulation has been exploited by a wide range of scientific studies. As the fundamental neural response inherits the spectral properties of the gazed flickering, the paradigm has been used to chart cortical characteristics and their relation to pathologies. However, despite its widespread adoption, the underlying neural mechanisms are not well understood.

Modeling brain dynamics after tumor resection using The Virtual Brain.

Brain tumor patients scheduled for tumor resection often face significant uncertainty, as the outcome of neurosurgery is difficult to predict at the individual patient level. Recently, simulation of the activity of neural populations connected according to the white matter fibers, producing personalized brain network models, has been introduced as a promising tool for this purpose. The Virtual Brain provides a robust open source framework to implement these models.

The single nucleotide variant n.60G>C in the microRNA-146a associated with susceptibility to drug-resistant epilepsy.

Objective: The aim of this study was to evaluate single nucleotide variants (SNVs) n.-411A > G (rs57095329) and n.60 G > C (rs2910164) in microRNA (miR)-146a, related to suppressing of TRAF6 with risk for epilepsy, as well as miR-146a and TRAF6 levels.

Semantic and perceptual priming activate partially overlapping brain networks as revealed by direct cortical recordings in humans.

Facilitation of object processing in the brain due to a related context (priming) can be influenced by both semantic connections and perceptual similarity. It is thus important to discern these two when evaluating the spatio-temporal dynamics of primed object processing. The repetition-priming paradigm frequently used to study perceptual priming is, however, unable to differentiate between the mentioned priming effects, possibly leading to confounded results.

Invasive Neuromodulation as a Treatment for Tinnitus: A Systematic Review.

Objective: Although the prevalence and burden of tinnitus is high, none of the available tinnitus treatments has been proven to be effective for the majority of tinnitus patients so far. Neuromodulation is currently gaining more interest to explore as tinnitus treatment. Because noninvasive neuromodulation has been shown to be effective in some tinnitus patients in the short term, more invasive techniques have been applied with variable success and without clear clinical applicability.

Vestibular schwannoma: natural growth and possible predictive factors.

Prediction of vestibular schwannoma (VS) growth would allow for a more differentiated follow-up protocol. The natural course of a VS and predictive factors of growth are investigated. Sixty-two sporadic VS cases diagnosed between 2003 and 2015 were included in this retrospective cohort study.

Is the Human Brain Capable of Controlling Seven Degrees of Freedom?

Background: Conventional rigid laparoscopic instruments offer five degrees of freedom (DOF). Robotic instruments add two independent DOFs allowing unconstrained directional steering. Several nonrobotic instruments have been developed with the additional DOFs, but with these devices, surgeon's wrist movements are not intuitively transmitted into tip movements.

Articulated Instruments and 3D Visualization: A Synergy? Evaluation of Execution Time, Errors, and Visual Fatigue.

. The introduction of advanced endoscopic systems, such as the Storz Image1S and the Olympus Endoeye, heralds a new era of 3-dimensional (3D) visualization. The aim of this report is to provide a comprehensive overview of the neurophysiology of 3D view, its relevance in videoscopy, and to quantify the benefit of the new 3D technologies for both rigid and articulated instruments.

A new dynamic model for in vitro evaluation of intravascular devices.

Introduction:: A dynamic model to evaluate thrombus formation on intravascular catheters in vitro is presented. The model enables fluid infusion, variation in the catheter orientation, and variable flow conditions. It was applied on a catheter used to shunt cerebrospinal fluid to a vein, a dural venous sinus, for the treatment of hydrocephalus.

Decoding Steady-State Visual Evoked Potentials From Electrocorticography.

We report on a unique electrocorticography (ECoG) experiment in which Steady-State Visual Evoked Potentials (SSVEPs) to frequency- and phase-tagged stimuli were recorded from a large subdural grid covering the entire right occipital cortex of a human subject. The paradigm is popular in EEG-based Brain Computer Interfacing where selectable targets are encoded by different frequency- and/or phase-tagged stimuli. We compare the performance of two state-of-the-art SSVEP decoders on both ECoG- and scalp-recorded EEG signals, and show that ECoG-based decoding is more accurate for very short stimulation lengths (i.

Hydroxyapatite cranioplasty: a retrospective evaluation of osteointegration in 17 cases.

Background: Cranial reconstruction with autologous bone is still the gold standard although several biomaterials are available to re-establish the integrity of the cranial vault. Due to their biological and morphological characteristics, hydroxyapatite implants show promising results in small clinical cohort studies, especially within the paediatric population. Its biocompatibility and osteoconductivity should allow the formation of osseous bridging at the skull-prosthesis interface.

Postarachnoiditis Anterior Spinal Arachnoid Cyst Formation with Compressive Myelopathy: Report of 2 Cases.

Background: Spinal cystic arachnoiditis is a rare complication of a subarachnoid haemorrhage or infectious meningitis. The inflammatory process leads to fibrosis, adhesions, and in severe cases cyst formation. Large arachnoid cysts are an uncommon cause of compressive myelopathy.