“Tricking the Brain” Using Immersive Virtual Reality: Modifying the Self-Perception Over Embodied Avatar Influences Motor Cortical Excitability and Action Initiation

To offer engaging neurorehabilitation training to neurologic patients, motor tasks are often visualized in virtual reality (VR). Recently introduced head-mounted displays (HMDs) allow to realistically mimic the body of the user from a first-person perspective (i.e., avatar) in a highly immersive VR environment. In this immersive environment,...

Nociceptive Intra-epidermal Electric Stimulation Evokes Steady-State Responses in the Secondary Somatosensory Cortex

Recent studies have established the presence of nociceptive steady-state evoked potentials (SSEPs), generated in response to thermal or intra-epidermal electric stimuli. This study explores cortical sources and generation mechanisms of nociceptive SSEPs in response to intra-epidermal electric stimuli. Our method was to stimulate healthy...

Transcranial Direct Current Stimulation Targeting the Entire Motor Network Does Not Increase Corticospinal Excitability

Transcranial direct current stimulation (tDCS) over the contralateral primary motor cortex of the target muscle (conventional tDCS) has been described to enhance corticospinal excitability, as measured with transcranial magnetic stimulation. Recently, tDCS targeting the brain regions functionally connected to the contralateral primary motor...

EEG Derived Laterality Metrics as a Biomarker for of Upper Limb Recovery in Stroke: An Explorative Study into EEG Biomarkers for Longitudinal Stroke Recovery

Problem: A biomarker that accurately predicts recovery of ischemic stroke for patients with poor baseline Fugl-Meyer Assessment of the Upper Extremity (FMA-UE) is lacking. Biomarkers that predict recovery while providing functional insight into the underlying neural process are highly desired for optimal clinical care. Objectives: This...

Rapid Acquisition of the Stimulus Response Relationship using Visual Evoked Potentials

The flash visual evoked potential (FVEP) is an electrical potential recorded with electroencephalogram (EEG) at the occipital cortex. Current FVEP assessment may be elaborated with the acquisition of stimulus response (SR) relation of the visual system. A drawback of this adjustment is the time required for data acquisition. This study aimed to...

Multisine frequency modulation of intra-epidermal electric pulse sequences: A novel tool to study nociceptive processing

A sustained sensory stimulus with a periodic variation of intensity creates an electrophysiological brain response at associated frequencies, referred to as the steady-state evoked potential (SSEP). The SSEPs elicited by the periodic stimulation of nociceptors in the skin may represent activity of a brain network that is primarily involved in...

Disentangling somatosensory evoked potentials of the fingers: Limitations and clinical potential

In searching for clinical biomarkers of the somatosensory function, we studied reproducibility of somatosensory potentials (SEP) evoked by finger stimulation in healthy subjects. SEPs induced by electrical stimulation and especially after median nerve stimulation is a method widely used in the literature. It is unclear, however, if the EEG...

StimTrack: An open-source software for manual transcranial magnetic stimulation coil positioning

Background During Transcranial Magnetic Stimulation (TMS) experiments researchers often use a neuronavigation system to precisely and accurately maintain coil position and orientation. New method This study aimed to develop and validate an open-source software for TMS coil navigation. StimTrack uses an optical tracker and an intuitive user...

Dynamic information flow based on EEG and diffusion MRI in stroke: A proof-of-principle study

In hemiparetic stroke, functional recovery of paretic limb may occur with the reorganization of neural networks in the brain. Neuroimaging techniques, such as magnetic resonance imaging (MRI), have a high spatial resolution which can be used to reveal anatomical changes in the brain following a stroke. However, low temporal resolution of MRI...

Nonlinearity in the Light Processing of the Human Visual System

Visual evoked potentials, i.e responses to visual stimulation as recorded using electroencephalography have indicated the existence of nonlinear behavior of the visual pathway. Nonlinearities and time delay in the visual system play an important role in understanding the complex nature of the visual system. This study investigated the nonlinear...