Search results for "Stimulation"
showing 10 items of 2192 documents
Early cortical processing of vection-inducing visual stimulation as measured by event-related brain potentials (ERP)
2019
Abstract Visual motion stimuli can induce the perception of self-motion in stationary observers (known as vection). In the present study, we investigated the sensory processing underlying vection by measuring the human event-related brain potentials (ERPs) elicited by the movement onset of a visual stimulus. We presented participants a visual stimulus consisting of alternating black-and-white vertical bars that moved in horizontal direction, creating the sensation of vection. The stimulus was presented on a screen that was divided into a central and a surrounding peripheral visual area. Both areas moved independently from each other, resulting in four different movement patterns: the periph…
Illusory contours and specific regions of human extrastriate cortex: evidence from rTMS
2003
Functional magnetic resonance imaging studies showed that perception of illusory contours is associated with extrastriate cortex activation prevailing on the right side. 1 Hz repetitive transcranial magnetic stimulation (rTMS) is able to induce lasting inhibition of cortical activity. The objective of the study was to investigate the role of extrastriate cortex in illusory contour perception inducing 1 Hz rTMS interference in healthy subjects. Eight healthy subjects underwent 1 Hz rTMS (600 pulses) through a figure-of-eight coil over right and left occipital cortex (O1 and O2 of 10/20 EEG system); sham magnetic stimulation on the same sites and right motor cortex rTMS (in three subjects) we…
Mapping of the human visual cortex using image-guided transcranial magnetic stimulation
2002
We describe a protocol using transcranial magnetic stimulation (TMS) to systematically map the visual sensations induced by focal and non-invasive stimulation of the human occipital cortex. TMS is applied with a figure of eight coil to 28 positions arranged in a 2x2-cm grid over the occipital area. A digitizing tablet connected to a PC computer running customized software, and audio and video recording are used for detailed and accurate data collection and analysis of evoked phosphenes. A frameless image-guided neuronavigational device is used to describe the position of the actual sites of the stimulation coils relative to the cortical surface. Our results show that TMS is able to elicit p…
Transcranial Direct Current Stimulation over the Right Inferior Parietal Cortex Reduces Transposition Errors in a Syllabic Reordering Task
2021
Evidence derived from functional imaging and brain-lesion studies has shown a strong left lateralization for language, and a complementary right hemisphere dominance for visuospatial abilities. Nevertheless, the symmetrical functional division of the two hemispheres gives no reason for the complexity of the cognitive operations involved in carrying out a linguistic task. In fact, a growing number of neuroimaging and neurostimulation studies suggest a possible right hemisphere involvement in language processing. The objective of this work was to verify the contribution of the left and right parietal areas in a phonological task. We applied anodal transcranial direct current stimulation (tDCS…
Assessment of the Short-Term Effects after High-Inductive Electromagnetic Stimulation of Pelvic Floor Muscles: A Randomized, Sham-Controlled Study
2020
Background: Physiotherapy should be performed by patients with stress or mixed urinary incontinence (SUI and MUI) to increase the strength and endurance of the pelvic floor muscles (PFMs). A method that can positively affect the pelvic floor is stimulation with high-inductive electromagnetic stimulation (HIES). The aim of the study was to evaluate the PFMs after the application of HIES in women with SUI and MUI by using surface electromyography (sEMG). Methods: This was a prospective, randomized, single-blind study with a sham intervention group. The participants were randomly assigned to the HIES group or sham group. The outcomes were features of the bioelectrical PFM activity assessed usi…
Prevention of OHSS: Current strategies and new insights
2010
Abstract Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic and potentially life threatening condition that affects young healthy patients. Many strategies have been proposed to prevent this syndrome. However, to avoid OHSS without compromising on IVF outcome is still a challenge. The most important action is to identify patients at risk even before ovarian stimulation is initiated and to give them special attention. Coasting is the most popular method to avoid/minimize OHSS. Cycle cancellation, cryopreservation, GnRH antagonists, GnRH agonists, i.v. albumin are other strategies that can provide some kind of benefit but do not completely avoid both early and late forms of OHSS and/or…
Prospective Validation of Facial Nerve Monitoring to Prevent Nerve Damage During Robotic Drilling
2019
Facial nerve damage has a detrimental effect on a patient's life, therefore safety mechanisms to ensure its preservation are essential during lateral skull base surgery. During robotic cochlear implantation a trajectory passing the facial nerve at <0.5 mm is needed. Recently a stimulation probe and nerve monitoring approach were developed and introduced clinically, however for patient safety no trajectory was drilled closer than 0.4 mm. Here we assess the performance of the nerve monitoring system at closer distances. In a sheep model eight trajectories were drilled to test the setup followed by 12 trajectories during which the ENT surgeon relied solely on the nerve monitoring system and…
Innovation in Neurosurgery: The Concept of Cognitive Mapping
2019
In recent years, advances in cortical-subcortical mapping, intraoperative neurophysiology, and neuropsychology have increased the ability to remove intrinsic brain tumors, expanding indications and maximizing the extent of resection. This has provided a significant improvement in progression-free survival, time of malignant transformation (in low-grade gliomas), and overall survival. Although current techniques enable preservation of language and motor functions during surgery, the maintenance of a complex set of functions defined with the term cognition is not always achievable. Cognition is defined as every neural process underlying a high human function and includes motor haptic and visu…
Prospective study of nocebo effects related to symptoms of idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF).
2020
The exact causes of Idiopathic Environmental Intolerance Attributed to Electromagnetic Fields (IEI-EMF, i.e., experience of somatic symptoms attributed to low-level electromagnetic fields) are still unknown. Psychological causation such as nocebo effects seem plausible. This study aimed to experimentally induce a nocebo effect for somatic symptom perception and examined whether it was reproducible after one week. We also examined whether these effects were associated with increased sympathetic activity and whether interoceptive accuracy (IAcc) moderated these relationships. Participants were recruited from the general population and instructed that electromagnetic exposure can enhance somat…
Effect of Different Display Types on Vection and Its Interaction With Motion Direction and Field Dependence
2017
Illusory self-motion (vection) can be generated by visual stimulation. The purpose of the present study was to compare behavioral vection measures including intensity ratings, duration, and onset time across different visual display types. Participants were exposed to a pattern of alternating black-and-white horizontal or vertical bars that moved either in vertical or horizontal direction, respectively. Stimuli were presented on four types of displays in randomized order: (a) large field of view dome projection, (b) combination of three computer screens, (c) single computer screen, (d) large field of view flat projection screen. A Computer Rod and Frame Test was used to measure field depen…