Search results for "FLEX"
showing 10 items of 1677 documents
Direction‐dependent visual cortex activation during horizontal optokinetic stimulation (fMRI study)
2005
Looking at a moving pattern induces optokinetic nystagmus (OKN) and activates an assembly of cortical areas in the visual cortex, including lateral occipitotemporal (motion‐sensitive area MT/V5) and adjacent occipitoparietal areas as well as ocular motor areas such as the prefrontal cortex, frontal, supplementary, and parietal eye fields. The aim of this functional MRI (fMRI) study was to investigate (1) whether stimulus direction‐dependent effects can be found, especially in the cortical eye fields, and (2) whether there is a hemispheric dominance of ocular motor areas. In a group of 15 healthy subjects, OKN in rightward and leftward directions was visually elicited and statistically compa…
Functional Magnetic Resonance Imaging Activations of Cortical Eye Fields during Saccades, Smooth Pursuit, and Optokinetic Nystagmus
2009
Saccades, smooth pursuit, and optokinetic nystagmus (OKN) are three basic eye movements in our ocular motor repertoire that enable us to explore the visual field. These eye movements are cortically controlled in different cortical eye fields, including the frontal eye fields (FEF) and parietal eye fields (PEF), as well as the motion-sensitive visual area MT+/V5. It is not known if this cortical control is organized in parallel cortico-cortical networks or in adjacent subregions of one system. Nor do we know where the specific eye fields are exactly located. Functional magnetic resonance imaging (fMRI) was used to investigate these open questions about the FEF, PEF, and MT+/V5. Activations o…
fMRI signal increases and decreases in cortical areas during small-field optokinetic stimulation and central fixation
2001
Small-field optokinetic nystagmus (OKN) was performed in seven healthy volunteers in order to analyze the activation and deactivation patterns of visual motion, ocular motor, and multisensory vestibular cortex areas by means of fMRI during coherent visual motion stimulation. BOLD signal decreases (deactivations) were found in the first and second long insular gyri and retroinsular areas (the human homologue of the parietoinsular vestibular cortex and the visual posterior sylvian area in the monkey) of both hemispheres, extending into the transverse temporal gyrus and inferior-anterior parts of the superior temporal gyrus (BA 22), and the precentral gyri at two separate sites (BA 4 and 6). F…
Cutaneous Recording and Stimulation of Muscles Using Organic Electronic Textiles
2016
International audience; Electronic textiles are an emerging field providing novel and non-intrusive solutions for healthcare. Conducting polymer-coated textiles enable a new generation of fully organic surface electrodes for electrophysiological evaluations. Textile electrodes are able to assess high quality muscular monitoring and to perform transcutaneous electrical stimulation.
In vivo fascicle behavior of the flexor hallucis longus muscle at different walking speeds.
2017
Ankle plantar flexor muscles support and propel the body in the stance phase of locomotion. Besides the triceps surae, flexor hallucis longus muscle (FHL) may also contribute to this role, but very few in vivo studies have examined FHL function during walking. Here, we investigated FHL fascicle behavior at different walking speeds. Ten healthy males walked overground at three different speeds while FHL fascicle length changes were recorded with ultrasound and muscle activity was recorded with surface electromyography (EMG). Fascicle length at heel strike at toe off and at peak EMG activity did not change with speed. Range of FHL fascicle length change (3.5-4.5 and 1.9-2.9 mm on average in s…
Physical fitness profile of elite athletes with intellectual disability
2006
The aim of this study was to investigate the physical fitness profile of high-performance athletes with intellectual disability (ID) in comparison with able-bodied individuals. Methods: Participants were 231 male and 82 female athletes. All evaluations were done using the EUROFIT physical fitness test. Results: In comparison with population data, both male and female athletes with ID score better for flexibility and upper body muscle endurance, but have similar or lower values for running speed, speed of limb movement, and strength measures. Compared with agematched physical education students, male athletes with ID score better for running speed and flexibility, and worse for strength. Fem…
Relationship between video head impulse test (vHIT) and caloric test in patients with vestibular neuritis.
2016
Abstract Introduction and objectives The caloric test is the gold standard for the loss of vestibular function diagnosis. The video head impulse test (vHIT) assesses the same reflex by using a video-assisted examination of the impulsive manoeuvre. We intend to compare the variation of results of the vHIT and the caloric test in patients with vestibular neuritis with respect to their initial condition at two different moments of their evolution and to check the level of correlation between them and with that of the DHI test. Methods We explored 20 patients with neuritis by using both vHIT and the caloric test on the same day. We assessed the correlation between these two tests and with the D…
Fragment reconstruction of coronary arteries using transesophageal echocardiography for coronary diagnostics
2008
Aims Ultrasound differs procedurally from the established methods for non-invasive coronary visualization and is therefore an interesting alternative for non-invasive diagnostics. In this study, fragment reconstruction of coronary arteries by transesophageal echocardiography (FRC-TEE) was investigated for the first time in a patient population being evaluated for coronary angiography. Methods and results Ultrasonic and angiographic findings were compared visually and using quantitative measurements in 50 patients. One hundred and seventy-one vessels were examined by FRC-TEE. The total lengths visualized were 9.6+ 1.7 cm for the right coronary artery, 7.0+ 1.1 cm for left circumflex, 3.9+ 1.…
Age-related decreases in motor unit discharge rate and force control during isometric plantar flexion.
2012
Aging is related to multiple changes in muscle physiology and function. Previous findings concerning the effects of aging on motor unit discharge rate (DR) and fluctuations in DR and force are somewhat contradictory. Eight YOUNG and nine OLD physically active males performed isometric ramp (RECR) and isotonic (ISO) plantar flexions at 10 and 20% of surface EMG at MVC. Motor unit (MU) action potentials were recorded with intramuscular fine-wire electrodes and decomposed with custom build software "Daisy". DR was lower in OLD in RECR-10% (17.9%, p0.001), RECR-20% (15.8%, p0.05), ISO-10% (17.7%, p0.01) and ISO-20% (14%, n.s.). In YOUNG force fluctuations were smaller at ISO-10% (72.1%, p0.001)…
Effects of joint angle and age on ankle dorsi- and plantar-flexor strength.
2007
This study aimed at examining the effects of joint angle and age on the maximal voluntary contraction (MVC) torque, for the agonist and antagonist muscle groups around the ankle, i.e., the dorsi- and plantar-flexors. To this aim, neural and muscular factors were investigated in two groups of healthy men: 11 young (mean age, 24 years) and 18 older (mean age, 78 years). Plantar-flexion (PF) and dorsiflexion (DF) isometric MVC torques were measured in three different ankle joint angles and surface electromyographic activities of the triceps surae and of the tibialis anterior muscles were recorded. The main findings were that the DF-to-PF MVC torque ratio varied with joint angle and age, indica…