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van der Wel Robrecht P R D RP Donders Institute for Brain, Cognition, and Behaviour, Radboud University Nijmegen, The - - 2009
Qualitative and quantitative changes characterize locomotion and rhythmic interlimb coordination at different speeds. Legs and hands do not move more or less quickly; they also adopt different relative coordination patterns. In the present article, the authors asked whether similar transitions occur for unimanual hand movements when speed is slowed below ...
Martin V - - 2008
Outside the laboratory, human movement typically involves redundant effector systems. How the nervous system selects among the task-equivalent solutions may provide insights into how movement is controlled. We propose a process model of movement generation that accounts for the kinematics of goal-directed pointing movements performed with a redundant arm. The ...
Fishbach Alon A Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, Illinois 60611, USA. - - 2008
Reaching hand movements tend to follow straight paths. Previous work has suggested that when visual feedback is perturbed such that straight hand motions are seen as curved motions, the motor system adapts to restore straight visual motion. We show that under a nonlinear visuomotor transformation, one that maps straight hand ...
Kovacs Attila J AJ Department of Health and Kinesiology, Texas A&M University, College Station, TX 77843-4243, - - 2009
The purpose of the present experiment was to observe the performance of participants attempting to produce a 1:1 bimanual coordination pattern with 90 degrees relative phase between the arms when feedback concerning the movement of the two limbs was integrated within a Lissajous plot and when this information was withdrawn. ...
Maoz Uri - - 2009
One long-established simplifying principle behind the large repertoire and high versatility of human hand movements is the two-thirds power law-an empirical law stating a relationship between local geometry and kinematics of human hand trajectories during planar curved movements. It was further generalized not only to various types of human movements, ...
Getz Wayne M - - 2008
The movement paths of individuals over landscapes are basically represented by sequences of points (x(i), y(i)) occurring at times t(i). Theoretically, these points can be viewed as being generated by stochastic processes that in the simplest cases are Gaussian random walks on featureless landscapes. Generalizations have been made of walks ...
Fryxell John M - - 2008
Recent theory suggests that animals should switch facultatively among canonical movement modes as a complex function of internal state, landscape characteristics, motion capacity, and navigational capacity. We tested the generality of this paradigm for free-ranging elk (Cervus elaphus) over 5 orders of magnitude in time (minutes to years) and space ...
Bartumeus Frederic - - 2008
The movement ecology framework depicts animal movement as the result of the combined effects of internal and external constraints on animal navigation and motion capacities. Nevertheless, there are still fundamental problems to understand how these modulations take place and how they might be translated into observed statistical properties of animal ...
Wittemyer George - - 2008
The internal state of an individual-as it relates to thirst, hunger, fear, or reproductive drive-can be inferred by referencing points on its movement path to external environmental and sociological variables. Using time-series approaches to characterize autocorrelative properties of step-length movements collated every 3 h for seven free-ranging African elephants, we ...
Kagerer Florian A FA Cognitive Motor Neuroscience Laboratory, Department of Kinesiology and Graduate Program in Neuroscience and Cognitive Science, University of Maryland School of Public Health, College Park, MD 20742, USA. - - 2009
A visuo-motor adaptation task was used to investigate the effects of this adaptation on the auditory-motor representation during reaching movements. We show that, following exposure to a rotated screen cursor-hand relationship, the movement paths during auditory conditions exhibited a similar pattern of aftereffects as those observed during movements to visual ...
Gomi Hiroaki - - 2008
Many neuroscience studies of arm control have attempted to explain how aimed movements are planned, generated, and corrected. The mechanisms of subconscious online reaching correction to a target shift are now being widely examined from computational, physiological, and pathological viewpoints. Recent evidence of a quick manual response to surrounding visual ...
Rutkowski Adam J - - 2009
We studied the relationship between vertical and lateral movements during free flight odor plume tracking by male moths, Manduca sexta, in a wind tunnel with the "horizon" set at different altitudes. Three-dimensional recordings revealed that the plume tracking males generated roughly equivalent movements vertically and laterally regardless of horizon height. ...
Wong Teser - - 2009
Motor control relies on multiple sources of information. To estimate the position and motion of the hand, the brain uses both vision and body-position (proprioception and kinesthesia) senses from sensors in the muscles, tendons, joints, and skin. Although performance is better when more than one sensory modality is present, visuomotor ...
McLean David L DL Department of Neurobiology and Behavior, w103 Mudd Hall Cornell University, Ithaca, New York 14853, - - 2008
The classic 'size principle' of motor control describes how increasingly forceful movements arise by the recruitment of motoneurons of progressively larger size and force output into the active pool. We explored the activity of pools of spinal interneurons in larval zebrafish and found that increases in swimming speed were not ...
Herwig Arvid - - 2009
In tool use, the intended external goals have to be transformed into bodily movements by taking into account the target-to-movement mapping implemented by the tool. In bimanual tool use, this mapping may depend on the part of the tool that is operated and the effector used (e.g. the left and ...
Wilmut Kate - - 2008
The accuracy of reaching movements improves when active gaze can be used to fixate on targets. The advantage of free gaze has been attributed to the use of ocular proprioception or efference signals for online control. The time course of this process, however, is not established, and it is unclear ...
Wainwright Peter C - - 2008
Animal movement and its muscular control are central topics in functional morphology. As experimentalists we often manipulate stimuli in a controlled setting or compare species to observe the degree of variation in movement and motor control of particular behaviors. Understanding and communicating the biological significance of these sources of variability ...
Dvorkin Assaf Y AY Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL 60611, USA. - - 2009
Reaching toward a visual target involves the transformation of visual information into appropriate motor commands. Complex movements often occur either while we are moving or when objects in the world move around us, thus changing the spatial relationship between our hand and the space in which we plan to reach. ...
Dessing Joost C JC Research Institute MOVE, Faculty of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands. - - 2009
Recent studies suggested that the control of hand movements in catching involves continuous vision-based adjustments. More insight into these adjustments may be gained by examining the effects of occluding different parts of the ball trajectory. Here, we examined the effects of such occlusion on lateral hand movements when catching balls ...
Gao Bo - - 2008
Skin marker-based stereophotogrammetry is the most widely used technique for human motion analysis but its accuracy is mainly limited by soft tissue artifact (STA) which reflects the non-rigidity of human body segments during activities. To compensate for the effects of STA and improve the accuracy of motion analysis, it is ...
Maslovat Dana - - 2009
Anchoring in cyclical movements has been defined as regions of reduced spatial or temporal variability [Beek, P. J. (1989). Juggling dynamics. PhD thesis. Amsterdam: Free University Press] that are typically found at movement reversal points. For in-phase and anti-phase movements, synchronizing reversal points with a metronome pulse has resulted in ...
Shiga Hiroshi - - 2009
To clarify the usefulness of the standard deviation (SD) and SD divided by the opening distance (SD/OD) of the opening lateral, closing lateral, and vertical components of the masticatory path as indicators of the stability of masticatory movement path. Fifty subjects masticated softened chewing gum on the unilateral side for ...
Luck Geoff - - 2008
A growing body of research utilizies computational feature-extraction methods to quantify both music and music-related movement. The use of signal processing and visualization techniques, for example, is widespread in the music information retrieval community. At the same time, similar techniques are being applied to the analysis of movement data acquired ...
Kwon Junghyun - - 2008
Recent studies have shown that the perception of natural movements-in the sense of being "humanlike"-depends on both joint and task space characteristics of the movement. This paper proposes a movement generation framework that merges two established techniques from gesture recognition and motion generation-hidden Markov models (HMMs) and principal components-into an ...
del Mar Delgado María - - 2008
Within the field of spatial ecology, it is important to study animal movements in order to better understand population dynamics. Dispersal is a nonlinear process through which different behavioral mechanisms could affect movement patterns. One of the most common approaches to analyzing the trajectories of organisms within patches is to ...
Toiviainen Petri - - 2008
Music listening is often associated with spontaneous body movements, frequently synchronized with the musical beat. While there exists an extensive body of work on synchronization of tapping, spontaneous movements to music have been investigated to a much lesser extent. The present study investigated the kinematic and kinetic aspects of spontaneous ...
Mirabella Giovanni G Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, - - 2009
A milestone on which relies the voluntary control of behavior is the ability to shape our motor output to meet the needs of the context which we are continuously facing. Even though it is solidly established that contextual information influence movement generation few studies have so far explored their effects ...
Dirnberger Georg - - 2008
The readiness potential (RP), a slow electroencephalographic (EEG) pre-movement potential, was used in earlier studies to determine the onset and order of neural processes preceding voluntary movement. Latencies in these studies were always calculated from the averaged RP, whereas onset times of individual trials remained inaccessible. The aim of this ...
Grierson Lawrence E M - - 2008
Examination of goal-directed movements has evidenced two processes of visually regulated online control: early trajectory control that operates to make movement adjustments on the basis of limb velocity comparisons to internally generated models of the expected limb velocity, and late trajectory control that uses allocentric information about the limb and ...
Repp Bruno H - - 2008
Phase correction during synchronization (finger tapping) with an isochronous auditory sequence is typically imperfect, requiring several taps to complete. However, two independent hypotheses predict that phase correction should approach perfection when the sequence tempo is slow. The present results confirm this prediction. The experiment used a phase perturbation method and ...
Balogh I - - 2009
Goniometry of the wrist is a feasible method for studying wrist movements in most hand-intensive work. The precision and accuracy of the method per se is good. For the knowledge on validity of field measurements, the size of imprecision is of importance. This study evaluated this condition during standardized circumstances. ...
Crapse Trinity B - - 2008
Our movements can hinder our ability to sense the world. Movements can induce sensory input (for example, when you hit something) that is indistinguishable from the input that is caused by external agents (for example, when something hits you). It is critical for nervous systems to be able to differentiate ...
Rodriguez Manuel - - 2008
It has been suggested that motor imagery (MI) has the basic components of real motion. This possibility was tested here in 17 healthy volunteers studied while performing or imaging a fast sequence of finger movements of progressive complexity, a fast and precise extension of the arm to touch a small ...
Ringenbach Shannon D - - 2008
This study investigated the relation between postural movement and upper-limb coordination stability. Adults produced bimanual circles using in-phase and anti-phase coordination patterns in time to an increasing rate metronome (i.e., movement-time instruction) in the horizontal (e.g., tabletop) and vertical (e.g., "wall" perpendicular to body) planes. All participants produced the instructed ...
Varoto Renato - - 2008
Generally, quadriplegic individuals have difficulties performing object manipulation. Toward satisfactory manipulation, reach and grasp movements must be performed with voluntary control, and for that, grasp force feedback is essential. A hybrid system aiming at partial upper limb sensory-motor restoration for quadriplegics was built. Such device is composed of an elbow ...
White Olivier - - 2008
In many nonprimate species, rhythmic patterns of activity such as locomotion or respiration are generated by neural networks at the spinal level. These neural networks are called central pattern generators (CPGs). Under normal gravitational conditions, the energy efficiency and the robustness of human rhythmic movements are due to the ability ...
van Doorn Robert R A - - 2008
Right-handed participants performed aimed, left- and right-hand movements toward a fixed target in speed and precision conditions. The purpose was to determine detailed hand differences in the temporal and spatial control during the course of a movement. The results showed that hand differences pertaining to spatial control of movement direction ...
Maki Yohko - - 2008
Mirror-symmetrical bimanual movement is more stable than parallel bimanual movement. This is well established at the kinematic level. We used functional MRI (fMRI) to evaluate the neural substrates of the stability of mirror-symmetrical bimanual movement. Right-handed participants (n=17) rotated disks with their index fingers bimanually, both in mirror-symmetrical and asymmetrical ...
Lai Shih-Chiung - - 2008
This study investigated the mutual information in the trajectories of discrete aiming movements on a computer controlled graphics tablet where movement time ( 300 - 2050 ms) was manipulated in a given distance (100 mm) and movement distance (15-240 mm) in 2 given movement times (300 ms and 800 ms ...
Kjeldsen Rick - - 2008
Vision-based head trackers have been around for some years and are even beginning to be commercialized, but problems remain with respect to usability. Users without the ability to use traditional pointing devices--the intended audience of such systems--have no alternative if the automatic bootstrapping process fails. There is room for improvement ...
Heath Matthew - - 2008
The authors manipulated the availability of monocular and binocular vision during the constituent planning and control stages of a goal-directed reaching task. Furthermore, trials were completed with or without online limb vision to determine whether monocular- or binocular-derived ego-motion cues influence the integration of visual feedback for online limb corrections. ...
Schaefer Sydney Y SY Department of Kinesiology, The Gerontology Center, Pennsylvania State University, University Park, PA 16802, - - 2008
The purpose of this study was to examine the mechanisms underlying control of distance during multijoint movements in different directions. The findings revealed 2 sequential muscle torque impulses, which correlated with 2 events in the hand acceleration profile. These 2 events occurred prior to peak velocity, characterizing control in the ...
Mirbagheri Mehdi M - - 2008
OBJECTIVES: To characterize the time-course of changes in motor recovery in the upper extremity of hemiparetic stroke survivors over a 1-year interval after stroke, and to use kinematic and kinetic recordings of elbow voluntary movement at 1 month to predict recovery over this 1-year period. DESIGN: Motor impairment was assessed ...
Pollick Frank E - - 2009
It has long been acknowledged that planar hand drawing movements conform to a relationship between movement speed and shape, such that movement speed is inversely proportional to the curvature to the power of one-third. Previous literature has detailed potential explanations for the power law's existence as well as systematic deviations ...
Pellizzer Giuseppe - - 2009
Children from 8 to 12 years of age drew figure-eights and ellipses at a self-chosen tempo on a digitizing tablet. Global aspects (perimeter and average speed) and local aspects (relation between instantaneous speed and curvature) of performance were analyzed across age groups and types of figures. We tested the predictions ...
Wallace Douglas G - - 2008
Rats use multiple sources of information to maintain spatial orientation. Although previous work has focused on rats' use of environmental cues, a growing number of studies have demonstrated that rats also use self-movement cues to organize navigation. This review examines the extent that kinematic analysis of naturally occurring behavior has ...
Fradet Laetitia - - 2008
Submovements that are frequently observed in the final portion of pointing movements have traditionally been viewed as pointing accuracy adjustments. Here we re-examine this long-lasting interpretation by developing evidence that many of submovements may be non-corrective fluctuations arising from various sources of motor output variability. In particular, non-corrective submovements may ...
Orgs Guido - - 2008
We presented professional dancers and non-dancers with videos of two movement styles, dance movements and everyday movements. Participants were asked to indicate by a button press to which category a movement belonged. We computed event-related desynchronization (ERD) in alpha and beta frequency bands between 7.5 and 25 Hz relative to ...
Perkins M C - - 2008
Understanding the movement of the active ingredient in relation to the other formulation components following application is crucial to an overall understanding of herbicide performance. We describe the novel use of time-of-flight secondary ion mass spectrometry (ToF-SIMS) as a tool for following the movement of herbicide formulation components into and ...
Trempe Maxime M Département de kinésiologie, Université de Montréal, Montreal, Quebec, Canada. - - 2008
One can adapt movement planning to compensate for a mismatch between vision and action. Previous research with prismatic lenses has shown this adaptation to be accompanied with a shift in the evaluation of one's body midline, suggesting an important role of this reference for successful adaptation. This interpretation leads to ...
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