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Wild Kelly S KS Faculty of Life Sciences, University of Manchester, PO Box 88, Sackville St, Manchester, M60 1QD, UK. - - 2010
This study took a quantitative approach to investigate movement kinematics during the imitation of goal-directed and non-goal directed movements. Motion tracking equipment was used to record the hand movements of 15 healthy participants during an imitation task involving aiming movements that varied in speed. We predicted that movement kinematics would ...
Pitetti Kenneth H - - 2009
Pedometer accuracy for steps and activity time during dynamic movement for youth with intellectual disabilities (ID) were examined. Twenty-four youth with ID (13 girls, 13.1 +/- 3.2 yrs; 11 boys, 14.7 +/- 2.7 yrs) were videotaped during adapted physical education class while wearing a Walk4Life 2505 pedometer in five locations ...
Jackson Heather Bird - - 2009
The ability to disperse among patches is central to population dynamics in fragmented landscapes. Although saproxylic (=dead wood dependent) insects live in extremely fragmented forest ecosystems and comprise a significant proportion of the biodiversity therein, few studies have focused on dispersal of members in this group. We quantified the terrestrial ...
Boukari Hacène - - 2009
Time-resolved confocal microscopy and fluorescence correlation spectroscopy were used to examine the movements of fluorescently labeled HIV-virions (approximately 100 nm) added to samples of human cervical mucus. Particle-tracking analysis indicates that the motion of most virions is decreased 200-fold compared to that in aqueous solution and is not driven by ...
Pham Quang-Cuong - - 2009
We investigated the nature of the control mechanisms at work during goal-oriented locomotion. In particular, we tested the effects of vision, locomotor speed, and the presence of via points on the geometric and kinematic properties of locomotor trajectories. We first observed that the average trajectories recorded in visual and nonvisual ...
Higham Timothy E - - 2010
Many animals lose and regenerate appendages, and tail autotomy in lizards is an extremely well-studied example of this. Whereas the energetic, ecological and functional ramifications of tail loss for many lizards have been extensively documented, little is known about the behaviour and neuromuscular control of the autotomized tail. We used ...
Hajnal Alen - - 2009
The current study examined whether the amount and location of available movement information influenced the stability of visuomotor coordination. Participants coordinated a handheld pendulum with an oscillating visual stimulus in an inphase and antiphase manner. The effects of occluding different amounts of phase at different phase locations were examined. Occluding ...
David Fabian J FJ Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, USA. - - 2009
It has previously been found that in fast point-to-point arm movements, proprioceptive feedback is centrally suppressed at the beginning of movement and is facilitated at a time that is correlated with temporal parameters of the planned movement. Here, we show that this correlation holds when subjects are explicitly instructed to ...
Reichenbach Alexandra - - 2009
Goal-directed movements are executed under the permanent supervision of the central nervous system, which continuously processes sensory afferents and triggers on-line corrections if movement accuracy seems to be compromised. For arm reaching movements, visual information about the hand plays an important role in this supervision, notably improving reaching accuracy. Here, ...
Colombo Roberto - - 2010
The aim of this study was to describe in detail a new method, called normalized force control parameter (nFCP), to measure changes in movement dynamics obtained during robot-aided neurorehabilitation, and to evaluate its ability to estimate the clinical scales. The study was conducted in a group of 18 subjects after ...
Hajnal Alen A Department of Psychology, University of Southern Mississippi, 118 College Dr. #5025, Hattiesburg, MS, 39406, USA. - - 2009
The current study examined whether the amount and location of available movement information influenced the stability of visuo-motor coordination. Participants coordinated a hand-held pendulum with an oscillating visual stimulus in an inphase and antiphase manner. The effects of occluding different amounts of phase at different phase locations were examined. Occluding ...
Short Fay - - 2009
Hari and Jousmaki (1996) found that motor activity is initiated more efficiently in response to stimuli located on the responding limb as opposed to near the limb. Our research investigated the basis for this difference in spatial coding. We conducted 8 experiments using virtual reality to manipulate the visual feedback ...
Ashenfelter Kathleen T - - 2009
This study examined the influence of sex, social dominance, and context on motion-tracked head movements during dyadic conversations. Windowed cross-correlation analyses found high peak correlation between conversants' head movements over short ( approximately 2-s) intervals and a high degree of nonstationarity. Nonstationarity in head movements was found to be positively ...
Schweizer Andreas - - 2009
The aim of the study was to investigate the influence of a preceding flexion or extension movement on the static interaction of human finger flexor tendons and pulleys concerning flexion torque being generated. Six human fresh frozen cadaver long fingers were mounted in an isokinetic movement device for the proximal ...
Broderick Michael P MP Motor Control Laboratory, Department of Kinesiology, Arizona State University, P.O. Box 870404, Tempe, AZ, 85287-0404, USA. - - 2009
To address the hypothesis that Parkinson's disease (PD) patients have deficits in controlling acceleration, a drawing task was used in which target size, frequency, and weight of pen were manipulated. In accordance with previous results, it was found that, relative to controls, PD patients produced movements at the required frequency, ...
Stegemöller Elizabeth L - - 2009
In young healthy adults, syncopated finger movements (movements between consecutive beats) are characterized by a frequency-dependent change in phase at movement rates near 2 Hz. A similar frequency-dependent phase transition is observed during bimanual anti-phase (asymmetric) tasks in healthy young adults, but this transition frequency is significantly lowered in both ...
Fux Michal - - 2009
The present study focused on the movements that owls perform before they swoop down on their prey. The working hypothesis was that owl head movements reflect the capacity to efficiently follow visually and auditory a moving prey. To test this hypothesis, five tame barn owls (Tyto alba) were each exposed ...
Grierson Lawrence E M - - 2009
This study was designed to examine the importance of vision to corrective processes associated with a mechanical perturbation to the limb during goal-directed aiming. With a hand held stylus, under vision and no vision conditions, performers reached to a target represented by the intersection of perpendicular lines. The stylus was ...
Thyrion Chloé - - 2009
It is generally agreed that motor imagery involves kinesthetic sensations especially as far as first-person imagery is concerned. It was proposed to determine the extent to which motor imagery and vibration-induced illusory sensations of movement are integrated perceptually. Imagined and illusory hand movements were evoked both separately and in various ...
Kazennikov Oleg - - 2009
Music performance is based on demanding motor control with much practice from young age onward. We have chosen to investigate basic bimanual movements played by violin amateurs and professionals. We posed the question whether position and string changes, two frequent mechanisms, may influence the time interval bowing (right)-fingering (left) coordination. ...
Bennequin Daniel - - 2009
Human movements show several prominent features; movement duration is nearly independent of movement size (the isochrony principle), instantaneous speed depends on movement curvature (captured by the 2/3 power law), and complex movements are composed of simpler elements (movement compositionality). No existing theory can successfully account for all of these features, ...
Polyakov Felix F Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, Israel. - - 2009
Some studies suggest that complex arm movements in humans and monkeys may optimize several objective functions, while others claim that arm movements satisfy geometric constraints and are composed of elementary components. However, the ability to unify different constraints has remained an open question. The criterion for a maximally smooth (minimizing ...
Harris Christopher M - - 2009
How should robotic or prosthetic arms be programmed to move? Copying human smooth movements is popular in synthetic systems, but what does this really achieve? We cannot address these biomimetic issues without a deep understanding of why natural movements are so stereotyped. In this article, we distinguish between 'functional' and ...
Pavely Stuart - - 2009
OBJECTIVES: To examine bilateral ball-passing skills whilst running amongst first-grade rugby union footballers. DESIGN: Within-group design SETTING: NSW Rugby Training facilities, Moore Park, Sydney. PARTICIPANTS: One international player used as a case study and twenty, first grade rugby union players. MAIN OUTCOME MEASURES: High-speed film was first used to capture ...
Marinovic Welber W Perception and Motor Systems Laboratory, School of Human Movement Studies, The University of Queensland, Blair Drive, St Lucia 4072, Brisbane, QLD, Australia. - - 2009
Two experiments aimed to provide an estimate of the last moment at which visual information needs to be obtained in order for it to be used to initiate execution of an interceptive movement or to withhold execution of such a movement. In experiment 1, we sought to estimate the minimum ...
Rauzi Matteo - - 2009
It remains largely unknown how large-scale tissue movements during development emerge from the interplay of different tensile forces associated with actomyosin networks. Solon et al. (2009) now report that a ratchet-like mechanism drives the movement of epithelial sheets during dorsal closure in embryos of the fruit fly Drosophila.
Dessing Joost C JC Research Institute MOVE, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorststraat 9, 1081 BT, Amsterdam, The Netherlands. - - 2009
Catching a ball involves a dynamic transformation of visual information about ball motion into motor commands for moving the hand to the right place at the right time. We previously formulated a neural model for this transformation to account for the consistent leftward movement biases observed in our catching experiments. ...
Bradberry Trent J - - 2009
During reaching or drawing, the primate cortex carries information about the current and upcoming position of the hand. Researchers have decoded hand position, velocity, and acceleration during center-out reaching or drawing tasks from neural recordings acquired invasively at the microscale and mesoscale levels. Here we report that we can continuously ...
Stegemöller Elizabeth L - - 2009
Performance of repetitive hand movements in patients with Parkinson's disease (PD) is characterized by slowness, reduced movement amplitude, and hesitation or arrests in ongoing movement. Currently, the factors and mechanisms contributing to impaired performance of these types of movement remain poorly understood. This study examined the effects of movement frequency ...
Moore James W - - 2009
We investigate the processes underlying the feeling of control over one's actions ("sense of agency"). Sense of agency may depend on internal motoric signals, and general inferences about external events. We used priming to modulate the sense of agency for voluntary and involuntary movements, by modifying the content of conscious ...
Hogendoorn Hinze - - 2009
Conflict between sensory modalities can be resolved by one modality overwriting another. For example, movement of a limb that is visible in a stationary visual afterimage results in selective fading of that limb in the afterimage. We investigated the interaction of these two sensory modalities by inducing a mismatch between ...
Petersen Carl - - 2009
PURPOSE: The time-motion characteristics and the within-athlete variability in movement patterns were quantified for the same male fast bowler playing One Day International (ODI) cricket matches (n=12). METHODS: A number of different time motion characteristics were monitored using a portable 5-Hz global positioning system (GPS) unit (Catapult, Melbourne, Australia). RESULTS: ...
Mashanova Alla - - 2010
Power laws are increasingly used to describe animal movement. Despite this, the use of power laws has been criticized on both empirical and theoretical grounds, and alternative models based on extensions of conventional random walk theory (Brownian motion) have been suggested. In this paper, we analyse a large volume of ...
Crevecoeur Frédéric - - 2009
The planning and control of motor actions requires knowledge of the dynamics of the controlled limb to generate the appropriate muscular commands and achieve the desired goal. Such planning and control imply that the CNS must be able to deal with forces and constraints acting on the limb, such as ...
Dall Philippa M - - 2010
The sit to stand movement is a key determinant of functional independence. Knowledge of the frequency with which the sit to stand movement is performed throughout the day could inform workplace ergonomics, but has rarely been examined. Healthy adults (n=140) were recruited from the general population. Free-living activity for each ...
Espay Alberto J - - 2009
Bradykinesia, characterized by slowness and decreased amplitude of movement, is often considered the most important deficit in Parkinson's disease (PD). The current clinical rating of bradykinesia in PD, based on the motor subscale of the Unified Parkinson's disease Rating Scale (UPDRS-III), does not individually weigh the impairments in speed and ...
Shapiro Mark B MB Sensory Motor Performance Program, Rehabilitation Institute of Chicago Physical Medicine and Rehabilitation, Northwestern University, Chicago, IL 60611, USA. - - 2009
It has previously been found that in point-to-point movements against inertial loads, proprioceptive feedback is centrally suppressed in the beginning of movement and is facilitated at a time that is correlated with the expected time of peak velocity. This suggests that the modulation of proprioceptive feedback is governed by the ...
Stamoulis Catherine C Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA. - - 2010
Brain oscillations modulated by motor behaviors are coupled to steady-state and other potentially unrelated to movement oscillations, with energy in the same frequency bands as the signals of interest. We applied matched filtering, a quasi-optimum signal detection technique, to decouple and extract movement-related signals from local field potentials (LFPs) recorded ...
Laboissière Rafael - - 2009
Speech production involves some of the most precise and finely timed patterns of human movement. Here, in the context of jaw movement in speech, we show that spatial precision in speech production is systematically associated with the regulation of impedance and in particular, with jaw stiffness--a measure of resistance to ...
Shih Ching-Hsiang - - 2009
This study assessed whether two persons with profound multiple disabilities would be able to control environmental stimulation using hand swing and a standard mouse with a newly developed mouse driver (i.e. a new mouse driver replaces standard mouse driver, and turns a mouse into a precise two-dimensional motion detector). The ...
Eder Andreas B - - 2009
Three experiments tested the influence of approach- and avoidance-related lever movements on the perception of masked affectively positive and negative stimuli. A motivational account of the bidirectional evaluation-behavior link predicted an enhanced detection of response-compatible stimuli, whereas a common-coding model predicted a reduced evaluative sensitivity toward such stimuli due to ...
Baudry Ludovic - - 2009
The movement amplitude is a key component of numerous elements in gymnastics. The purpose of the present study is to highlight the most pertinent amplitude variable of the circle performed on the pedagogic pommel horse. Twelve gymnasts (6 expert gymnasts vs. 6 nonexpert gymnasts) performed 10 circles on this event. ...
Flanagin Virginia L - - 2009
It is unclear how subjects perceive and process self-motion cues in virtual reality environments. Movement could be perceived as passive, akin to riding in a car, or active, such as walking down the street. These two very different types of self-motion were studied here using motor imagery in fMRI. In ...
Kowalska Malgorzata A - - 2009
Two different methods to measure binocular longitudinal corneal apex movements were synchronously applied. High-speed videokeratoscopy at a sampling frequency of 15 Hz and a custom-designed ultrasound distance sensor at 100 Hz were used for the left and the right eye, respectively. Four healthy subjects participated in the study. Simultaneously, cardiac ...
Cloete Steven R SR School of Human Movement Studies, University of Queensland, St Lucia, QLD, Australia. - - 2009
When attempting to perform bi-phasic steering movements (such as a lane change) in the absence of visual and inertial feedback, drivers produce a systematic heading error in the direction of the lane change (Wallis et al., Curr Biol 12(4):295-299, 2002; J Exp Psychol Hum Percept Perform 33(55):1127-1144, 2007). Theories of ...
Siegle Joshua H JH Department of Human Perception, Cognition and Action, Max Planck Institute for Biological Cybernetics, Tübingen, - - 2009
In order to optimally characterize full-body self-motion perception during passive translations, changes in perceived location, velocity, and acceleration must be quantified in real time and with high spatial resolution. Past methods have failed to effectively measure these critical variables. Here, we introduce continuous pointing as a novel method with several ...
Maslovat Dana D School of Human Kinetics, University of British Columbia, Vancouver, BC, Canada. - - 2009
For synchronous bimanual movements, we have shown that a different amplitude can be prepared for each limb in advance and this preparation improves with practice (Maslovat et al. 2008). In the present study, we tested whether an asynchronous bimanual movement can also be prepared in advance and be improved with ...
Archambault Philippe S - - 2009
The parietal mechanisms for the control of hand movement trajectory were studied by recording cell activity in area 5 of monkeys making direct reaches to visual targets and online corrections of movement trajectory, after change of target location in space. The activity of hand-related cells was fitted with a linear ...
Seizova-Cajic Tatjana T Faculty of Health Sciences, University of Sydney, Lidcombe, NSW 1825, Australia. - - 2009
We report an aftereffect in perception of the extent (or degree or range) of joint movement, showing for the first time that a prolonged exposure to a passive back-and-forth movement of a certain extent results in a change in judgment of the extent of a subsequently presented movement. The adapting ...
Khezri Mahdi - - 2009
Electromyogram signal (EMG) is an electrical manifestation of contractions of muscles. Surface EMG (sEMG) signal collected from the surface of skin has been used in diverse applications. One of its usages is in pattern recognition of hand prosthesis movements. The ability of current prosthesis devices has been generally limited to ...
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