Examination of the interaction of parameters for low-intensity focused ultrasound of the human motor cortex.

Background: Low-intensity focused ultrasound (LIFU) is a promising form of non-invasive neuromodulation characterized by a rich parameter space that includes intensity, duration, duty cycle and pulsing strategy. The effect and interaction of these parameters to affect human brain activity is poorly understood. A better understanding of how parameters interact is critical to advance LIFU as a potential therapeutic.

Corticospinal excitability and voluntary activation of the quadriceps muscle is not affected by a single session of anodal transcutaneous spinal direct current stimulation in healthy, young adults.

The aim of the present study was to determine if anodal transcutaneous spinal direct current stimulation (tsDCS) affects corticospinal excitability (CSE) and voluntary activation (VA) of the quadriceps femoris muscle (QM). This was a double-blind, randomized study in which spine-shoulder anodal tsDCS (active electrode centered over T11-12, 2.5 mA, 20 min) was applied in a seated position.

Spinal motor evoked responses elicited by transcutaneous spinal cord stimulation in chronic stroke: Correlation between spinal cord excitability, demographic characteristics, and functional outcomes.

Transcutaneous spinal cord stimulation (tSCS) is becoming a promising neuromodulation technique to promote motor recovery in various neurological conditions, including stroke. As this intervention moves forward into clinical practice, it is important to understand how the elicited neurophysiological measures are related to the functional and neuromuscular deficits of the population of interest in order to personalize tSCS interventions and assess its effectiveness. Specifically, neurophysiological measurements of spinal cord excitability can be achieved by recording with EMG spinal motor evoked responses (sMERs) in muscles after applying single pulses of tSCS to the spinal cord.

Avoidance and Management of Complications in Retrosigmoid Approach to Vestibular Schwannomas.

An experience with two rare complications during surgery of vestibular schwannomas (VSs) is presented, and measures to avoid and manage the complications are discussed.Case A: Spinal cord ischemia in semi-sitting position: A 47-year-old with a giant vestibular schwannoma (VS) underwent surgery through a retrosigmoid approach in the semi-sitting position. The intraoperative phase was uneventful, except for an episode of moderate hypotension.

Sudden Loss of Motor-Evoked Potentials (MEPs) During the Resection of A Nondominant Insular Glioma: Case Report and Management Review.

A 43-year-old man was admitted into the emergency room at our hospital after presenting with a tonic-clonic seizure. MRI showed a right-side operculo-insular tumor. This was treated by performing a craniotomy under general anesthesia with intraoperative monitoring.

SSVEP modulation via non-volitional neurofeedback: anproof of concept.

Neuronal oscillatory patterns are believed to underpin multiple cognitive mechanisms. Accordingly, compromised oscillatory dynamics were shown to be associated with neuropsychiatric conditions. Therefore, the possibility of modulating, or controlling, oscillatory components of brain activity as a therapeutic approach has emerged.

You Are as Old as the Connectivity You Keep: Distinct Neurophysiological Mechanisms Underlying Age-Related Changes in Hand Dexterity and Strength.

Background: Aging can lead to a decline in motor control. While age-related motor impairments have been documented, the underlying changes in cortico-cortical interactions remain poorly understood.

Methods: We took advantage of the high temporal resolution of dual-site transcranial magnetic stimulation (dsTMS) to investigate how communication between higher-order rostral premotor regions and the primary motor cortex (M1) influences motor control in young and elderly adults.

Stimulation-Evoked Resonant Neural Activity in the Subthalamic Nucleus Is Modulated by Sleep.

Background: Deep brain stimulation is a treatment for advanced Parkinson's disease and currently tuned to target motor symptoms during daytime. Parkinson's disease is associated with multiple nocturnal symptoms such as akinesia, insomnia, and sleep fragmentation, which may require adjustments of stimulation during sleep for best treatment outcome.

Objectives: There is a need for a robust biomarker to guide stimulation titration across sleep stages.

Unconscious goal pursuit strengthens voluntary force during sustained maximal effort via enhanced motor system state.

Maximal voluntary force is known to be enhanced by shouting during sustained maximal voluntary contraction (MVC) via the enhancement of motor cortical excitability. However, whether excitatory input to the primary motor cortex from areas other than the motor-related cortical area induces muscular force-enhancing effects on the exertion of sustained maximal force remains unclear. Therefore, by examining motor evoked potentials to transcranial magnetic stimulation during sustained MVC and assessing handgrip force, the present study aimed to investigate the effects of subliminal goal-priming with motivational rewards on the state of the motor system.

State-Dependent Motor Cortex Stimulation Reveals Distinct Mechanisms for Corticospinal Excitability and Cortical Responses.

Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation method that modulates brain activity by inducing electric fields in the brain. Real-time, state-dependent stimulation with TMS has shown that neural oscillation phase modulates corticospinal excitability. However, such motor evoked potentials (MEPs) only indirectly reflect motor cortex activation and are unavailable at other brain regions of interest.

Electrophysiological indexes of the cognitive-motor trade-off associated with motor response complexity in a cognitive task.

Complex actions require more cognitive and motor control than simple ones. Literature shows that to face complexity, the brain must make a compromise between available resources usually giving priority to motor control. However, literature has minimally explored the effect of the motor response complexity on brain processing associated with cognitive tasks.

P1 evoked by facial expression images is enhanced in Parkinson's disease patients with depressive symptoms.

Introduction: Depressive symptoms are most common non-motor symptoms in Parkinson's disease (PD), which is often overlooked due to absence of rapid and objective diagnostic biomarkers. Electroencephalography (EEG)-based event-related potentials (ERPs) is commonly used to assess emotional processes. The aim of this study was to investigate changes in ERPs in PD patients exhibiting depressive symptoms and to provide a reliable biomarker for assisting in the diagnosis of PD with depressive symptoms.

The influence of depth of sedation on motor evoked potentials monitoring in youth from 4 to 23 years old: preliminary data from a prospective observational study.

Introduction: The influence of various levels of sedation depth on motor evoked potentials (MEP) reproducibility in youth is still unclear because of a lack of data. We tested the hypothesis that a deeper level of total intravenous anesthesia (TIVA) [bispectral index (BIS) 40 ± 5 compared to 60 ± 5] can affect surgeon-directed MEP and their interpretation in youths.

Methods: All patients received TIVA combined with propofol and remifentanil.

Clinical efficacy of low-dose Perampanel correlates with neurophysiological changes in familial adult myoclonus epilepsy 2.

Familial adult myoclonus epilepsy (FAME) management relies on antiseizure medications (ASMs), which inadequately address myoclonus and cortical tremor. This study evaluates Perampanel (PER), an AMPA-receptor antagonist, for treating FAME symptoms. Fifteen FAME2 patients participated in an observational prospective study.

Does Post-Tetanic Transcranial Stimulation Augment the Wave Amplitudes of Spinal Cord Evoked Potential (Tc-SCEP)?

Study Design: Prospective within-subjects study.

Objectives: Although motor-evoked potential (MEP) amplitude can reportedly be increased by tetanic stimulation of the peripheral nerves before transcranial electrical stimulation (TES), no reports have described on whether tetanic transcranial stimulation augments the wave amplitudes of spinal cord-evoked potentials (Tc-SCEP). The primary purpose of this study was to investigate whether tetanic stimulation induces waveform amplification of Tc-SCEP.

Fluoxetine does not influence response to continuous theta burst stimulation in human motor cortex.

Aim: Selective serotonin reuptake inhibitors are thought to exert a clinical effect through various mechanisms, including through alteration in synaptic plasticity. Repetitive transcranial magnetic stimulation can induce temporary changes in synaptic excitability in cerebral cortex that resemble long-term potentiation and long-term depression that serve as a measure of synaptic plasticity in vivo. A version of repetitive transcranial magnetic stimulation called continuous theta burst stimulation can induce inhibition of cortical excitability that can be measured through a motor evoked potential.

Neurophysiologic inhibitory factors influencing subsequent ankle sprain in collegiate male athletes: a prospective cohort study.

Many athletes with recurrent ankle sprains complain of neurophysiological deficits related to chronic ankle instability (CAI). However, it remains unclear how changes in the corticospinal pathway affect the potential risk of subsequent ankle sprains. The purpose of this study was to investigate whether the corticospinal excitability (input-output properties) and silent period (SP) could be related to the risk of subsequent ankle sprains among athletes.

Neurophysiological evidence of motor contribution to vicarious affective touch.

Understanding observed interpersonal touch, particularly the so-called affective touch targeting the CT fibers, is essential for social interactions. Research has documented that observing other people being touched activates the same cortical areas involved in direct tactile experiences. However, observing interpersonal touch also activates an inner simulation of the movements in the observer's motor system.

Transcranial MEPs predict clinical outcome during minimally invasive dorsal decompression for cervical spondylotic myelopathy.

Objectives: Motor evoked potential (MEP) monitoring is a reliable method for real-time assessment of corticospinal tract integrity. However, the potential benefits of MEP monitoring during degenerative spine surgery remain controversial. This study aims to determine the role of MEP monitoring during surgery for cervical spondylotic myelopathy (CSM) in prediction of prognosis.