A5103031613- Muscle activation and electromyography studies
- Motor Control and Adaptation
- Neuroscience and Neural Engineering
- EEG and Brain-Computer Interfaces
- Nuclear physics research studies
- Transcranial Magnetic Stimulation Studies
- Nuclear Physics and Applications
- Spinal Cord Injury Research
- Stroke Rehabilitation and Recovery
- Neurological disorders and treatments
- Neural dynamics and brain function
- Tactile and Sensory Interactions
- Nuclear reactor physics and engineering
- Zebrafish Biomedical Research Applications
- Robotic Locomotion and Control
- Botulinum Toxin and Related Neurological Disorders
- Quantum Chromodynamics and Particle Interactions
- Nerve Injury and Rehabilitation
- Cerebral Palsy and Movement Disorders
- Radiation Detection and Scintillator Technologies
- Pain Mechanisms and Treatments
- Particle Detector Development and Performance
- Veterinary Orthopedics and Neurology
- Sports Performance and Training
- Neurobiology and Insect Physiology Research
University of Alberta
2012-2022
GSI Helmholtz Centre for Heavy Ion Research
2010-2022
Women and Children’s Health Research Institute
2016-2019
University of Groningen
2019
Nara Women's University
2019
Institute of Chemical Technology
2013
Justus-Liebig-Universität Gießen
2009
Giessen School of Theology
2009
Comenius University Bratislava
2008
Harlow College
1997
1. Implanted semimicroelectrodes were used to record single afferent fiber discharges from L7 dorsal roots during unrestrained walking in the conscious cat. 2. A series of tests identify an a short period anesthesia following each recording session. The majority afferents muscle spindle primary endings hindlimb muscles. 3. Ankle extensor primaries generally showed their highest firing rates that phase stepping which they passively stretched. During active contraction there was evidence...
1. In this investigation, we tested the hypothesis that muscle spindle afferents signaling length of hind-leg flexor muscles are involved in terminating extensor activity and initiating flexion during walking. The hip iliopsoas (IP) ankle flexors tibialis anterior (TA) digitorum longus (EDL) were stretched or vibrated at various phases step cycle spontaneously walking decerebrate cats. Changes electromyogram amplitude, duration, timing then examined. effects electrically stimulating group I...
1 Back pain is known to change motor patterns of the trunk. The purpose this study was examine output erector spinae (ES) muscles during in lumbar region. First, their voluntary activation assessed flexion and re-extension Second, effects cutaneous muscle on ES stretch reflex were measured, since increased gain has been suggested underlie tone painful muscles. 2 trunk movement electromyographical (EMG) signals from right left compared with values before pain. Controlled induced by infusion...
1. In this study we tested the hypothesis that ensemble activity in human cutaneous sensory afferents evoked by stretching of skin over and around finger joints contributes to conscious perception movement fingers. 2. nineteen normal adults, ensembles were activated either electrical stimulation, delivered through an array electrodes on dorsum hand fingers, or mechanical joints. The was applied threads stuck skin, such a way as avoid minimize moving underlying applying pressure tendons...
1. The discharge activity of muscle spindle endings located in tail and hind limb muscles was recorded during voluntary movements the cat. 2. During active shortening receptor-bearing muscles, both primary secondary tended to fall silent. This more pronounced, higher rate shortening. We suggest that unobstructed which velocities exceed 0.2 resting lengths per second (lr/sec), firing patterns afferents are dominated by their responses length variations. At lower than lr/sec, fusimotor action...
1. Implanted dorsal root electrodes were used to record discharge trains of single spindle primary afferents (Ia's) the cat's hind limb during different types movement. 2. The length ipsilateral ankle extensors was continuously monitored by an implanted gauge. Length changes occurring active stepping subsequently passively reproduced brief anaesthesia. 3. A comparison Ia responses in and simulated step cycles revealed that moderate fusimotor drive extensor spindles probably occurred mainly,...
We report the measurement of reaction cross sections (${\ensuremath{\sigma}}_{R}^{\mathrm{ex}}$) $^{27,29}\mathrm{F}$ with a carbon target at RIKEN. The unexpectedly large ${\ensuremath{\sigma}}_{R}^{\mathrm{ex}}$ and derived matter radius identify $^{29}\mathrm{F}$ as heaviest two-neutron Borromean halo to date. is attributed neutrons occupying $2{p}_{3/2}$ orbital, thereby vanishing shell closure associated neutron number $N=20$. results are explained by state-of-the-art model...
The main purpose of this study was to collate population data on the firing characteristics muscle afferents recorded chronically during normal stepping in cats. Ensemble profiles forty‐seven spindle and tendon organ were compiled from stored data. relationships between displacement force signals analysed with help mathematical models response primary secondary organs. Whereas hamstring could be predicted reasonable accuracy length velocity alone, triceps surae deviated profiles,...
This study was prompted by recent evidence for the existence of positive force feedback in feline locomotor control. Our aim to establish some basic properties relation load compensation, stability, intrinsic muscle properties, and interaction with displacement feedback. In human subjects, muscles acting about wrist ankle were activated feedback-controlled electrical stimulation. The signals obtained from sensors monitoring displacement. filtered mimic transduction mammalian tendon organ...
Prochazka, Arthur, Deborah Gillard, and David J. Bennett. Implications of positive feedback in the control movement. Neurophysiol. 77: 3237–3251, 1997. In this paper we review some theoretical aspects The focus is mainly on new theories regarding reflexive role sensory signals from mammalian tendon organ afferents. static postures these afferents generally mediate negative force feedback. But locomotion there evidence a switch to action. Positive often associated with instability...
The aim of this work was to compare the ability several mathematical models predict firing characteristics muscle spindle primary afferents recorded chronically during normal stepping in cats. Ensemble profiles nine hamstring (presumed group Ia) were compiled from stored data 132 step cycles. Three sets corresponding slow, medium and fast steps generated by averaging groups cycles aligned peak length each cycle. Five obtained literature compared. Each these used averaged signals. also...
The aim of this study was to produce a dynamic model the spatiotemporal activation ensembles alpha motoneurons (MNs) in cat lumbosacral spinal cord during locomotor step cycle. coordinates MNs 27 hindlimb muscles were digitized from transverse sections spanning entire enlargement caudal part L 4 rostral S 1 segments. Outlines gray matter also digitized. Models generated these data and displayed on computer screen as three-dimensional (3-D) images. We compiled chart electromyographic (EMG)...
1. In the cat step cycle electromyographic (EMG) activity in ankle extensor muscles commences approximately 70 ms before foot contact. There is a sharp peak between 10 and 25 after contact EMG then declines for remainder of stance phase. It has been posited that abrupt transition consequence reflexes elicited by large barrage afferent input signals touchdown. However, it also possible basic profile might be generated within CNS, with little modification input. 2. These ideas were tested 11...
Abstract Clinical assessment of rigidity in parkinsonian patients is largely qualitative. The reliability and validity the assessments are sometimes doubt. Several “engineering” methods quantifying have been described, but none has adopted into general clinical practice. A possible reason that these differ crucial aspects from exam. We therefore tackled problem by monitoring exam itself, using small sensors to measure forces displacements applied. Limb impedance(Z) was computed parameter...
1. The discharge of various hindlimb muscle afferents was recorded during paw shakes in normal cats with the use floating dorsal root electrodes. 2. Muscle spindle group Ia-afferents and tendon organ Ib-afferents fired lengthening, reaching very high peak rates then silencing at or shortly after onset shortening. timing Ia firing consistent predictions a linear model as well responses endings subjected to identical length variations separate anesthetized cats. 3. In latter “reconstruction”...