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Bouquet C A - - 2007
The perception of a human actor performing movements may involve processes related to action execution. This resonance of the motor system may support observational learning and imitation, and could also explain the fact that observers'/actors' movements are disturbed by the observation of a human model making different movements (Kilner et ...
Arzamarski Ryan R Center for the Ecological Study of Perception and Action, Department of Psychology, U-1020, University of Connecticut, 406 Babbidge Rd, Storrs, CT 06269-1020, USA. - - 2007
Part of understanding how acts are coordinated is identifying the information that guides movements. In the case of catching a ball within arm's reach, that identification has been complicated by empirical disparities concerning hand-movement reversals during catching. Jacobs and Michaels found unilateral reversals in a paradigm in which balls swung ...
Fiorio Mirta - - 2007
Perception of limb position and motion is abnormal in Parkinson's disease (PD). Despite the fact that the processing of proprioceptive inputs is inherently temporal, most studies have assessed spatial aspects of proprioception in PD patients. Here, we use a recently described method to test whether deficits also exist in temporal ...
de Freitas Sandra Maria Sbeghen Ferreira - - 2007
This study examined the hypothesis that the degree to which motor redundancy is used to coordinate joint motions for reaching is influenced by motor planning and enhanced when the task requires greater movement flexibility. Subjects reached at arm's length to the same centrally placed target under conditions where the target ...
Scheidt Robert A - - 2007
We characterized how hemiparetic stroke survivors and neurologically intact individuals adapt reaching movements to compensate for unpredictable environmental perturbations. We tested the hypotheses that like unimpaired subjects, hemiparetic stroke survivors adapt using sensory information obtained during only the most recent movements and that the reliability of target acquisition decreases as ...
Meulenbroek Ruud G J RG Nijmegen Institute for Cognition and Information, Radboud University Nijmegen, PO Box 9104, 6500 HE Nijmegen, The Netherlands. - - 2007
Here we report a study of joint-action coordination in transferring objects. Fourteen dyads were asked to repeatedly reposition a cylinder in a shared workspace without using dialogue. Variations in task constraints concerned the size of the two target regions in which the cylinder had to be (re)positioned and the size ...
Mazyn Liesbeth I N - - 2007
Two experiments were conducted in order to investigate the adaptability and associated strategies of the human perceptuo-motor system to deal with changing constraints. In a catching task, perceptual-motor constraints were internally controlled by coupling movement onset of the catch and the illumination circuit in the lab: upon the first movement ...
Tricon Veronique - - 2007
The present study focuses on the organization of kinematic synergy and its adaptation to an unstable support surface during upper trunk movements in aging adults. Seven healthy aging adults (49-66 years old) were instructed to bend the trunk forward (the head and the trunk together) by about 40 degrees and ...
Bhatt Dimple H - - 2007
Animals can produce movements of widely varying speed and strength by changing the recruitment of motoneurons according to the well-known size principle. Much less is known about patterns of recruitment in the spinal interneurons that control motoneurons because of the difficulties of monitoring activity simultaneously in multiple interneurons of an ...
Hayes Spencer J - - 2007
We required two groups of participants to observe an end-point model (ENDPT) while another two groups viewed a full-body, point-light model (FULL) to determine the role of relative motion information in acquisition of a multi-limb, whole-body action. One ENDPT and one FULL group also bowled a ball. Following retention, all ...
Warren Paul A - - 2007
A moving observer needs to be able to estimate the trajectory of other objects moving in the scene. Without the ability to do so, it would be difficult to avoid obstacles or catch a ball. We hypothesized that neural mechanisms sensitive to the patterns of motion generated on the retina ...
Pawar Tanmay - - 2007
Ambulatory ECG analysis is adversely affected by motion artifacts induced due to body movements. Knowledge of the extent of motion artifacts facilitates better ECG analysis. In [1], an unsupervised method using recursive principal component analysis (RPCA) was used to detect transitions between body movements. In this paper, we endeavour to ...
Cohen Rajal G - - 2007
Taking a cue from recent discoveries of directional bias in microsaccades during visual fixation, we investigated directional bias in tremor during manual pointing. Subjects memorized and then performed patterns of alternating postures and voluntary movements. The directions of the tiny movements occurring during periods of intended stillness were predictive of ...
Balslev Daniela - - 2007
During visually guided movements both vision and proprioception inform the brain about the position of the hand, so interaction between these two modalities is presumed. Current theories suggest that this interaction occurs by sensory information from both sources being fused into a more reliable, multimodal, percept of hand location. In ...
Huang Jian - - 2007
This paper deliberates the spatial cognitive ability of the moving distance of the human hand, which is measured by using motion capture. Before the movement begins, the subject is shown a standard length. Then, both horizontal and vertical blindfold hand movements were measured using the proposed protocol for six right ...
Vaidyanathan Ravi - - 2007
The goal of this work is to discover and extract critical features from pressure signals in the aural canal resulting from actions (tongue movements) within the oral cavity. Its scope encompasses the identification of critical features of pressure signals sensed in the ear resulting from tongue motion and the development ...
Christe Blaise - - 2007
In this study, we developed a digitizing tablet-based instrument for the clinical assessment of human voluntary movements targeting motor processes of planning, programming and execution. The tool was used to investigate an adaptation of Fitts' reciprocal tapping task [10], comprising four conditions, each of them modulated by three indices of ...
Hansen Steve - - 2007
We examined the spatial and temporal limitations of the visual corrective process in goal-directed aiming, as well as gender differences in online control. An initial experiment was conducted to test the utility of a monocular switch procedure as a method of rapidly introducing a visual perturbation. The results revealed minimal ...
Jonas M - - 2007
The posterior inferior frontal gyrus (pIFG) and anterior inferior parietal lobule (aIPL) form the core regions of the human "mirror neuron system" that matches an observed movement onto its internal motor representation. We used event-related functional MRI to examine whether simple intransitive finger movements evoke "mirror activity" in the pIFG ...
Kilner James - - 2007
It has previously been shown that observing an action made by a human, but not by a robot, interferes with executed actions (Kilner, Paulignan, & Blakemore, 2003). Here, we investigated what aspect of human movement causes this interference effect. Subjects made arm movements while observing a video of either a ...
Tsibidis George D - - 2007
The nematode Caenorhabditis elegans responds to an impressive range of chemical, mechanical and thermal stimuli and is extensively used to investigate the molecular mechanisms that mediate chemosensation, mechanotransduction and thermosensation. The main behavioral output of these responses is manifested as alterations in animal locomotion. Monitoring and examination of such alterations ...
Schtickzelle Nicolas - - 2007
Dispersal between habitat patches is a key process in the functioning of (meta)populations. As distance between suitable habitats increases, the ongoing process of habitat fragmentation is expected to generate strong selection pressures on movement behaviour. This leads to an increase or decrease of dispersal according to its cost relative to ...
Sosnik Ronen R Weizmann Institute of Science, Rehovot 71600, Israel. - - 2007
We recently showed that extensive training on a sequence of planar hand trajectories passing through several targets resulted in the co-articulation of movement components and in the formation of new movement elements (primitives) (Sosnik et al. in Exp Brain Res 156(4):422-438, 2004). Reduction in movement duration was accompanied by the ...
Clark Damon A - - 2007
When navigating spatial thermal gradients, the nematode C. elegans migrates toward colder temperatures until it reaches its previous cultivation temperature, exhibiting cryophilic movement. The strategy for effecting cryophilic movement is the biased random walk: C. elegans extends (shortens) periods of forward movement that are directed down (up) spatial thermal gradients ...
Huber Jessica E - - 2006
Examination of movement parameters and consistency has been used to infer underlying neural control of movement. However, there has been no systematic investigation of whether the way individuals are asked (or cued) to increase loudness alters articulation. This study examined whether different cues to elicit louder speech induce different lip ...
Baguma-Nibasheka M - - 2006
As developmental biologists we study the role of fetal movements in providing continuity between prenatal and postnatal life. There are two major categories of fetal motility. The first category consists of movements that have an obvious effect on the survival or development of the fetus (e.g., changes of position, sucking ...
Thompson Shelby G - - 2007
The current experiment suggests that the speed/accuracy tradeoff is composed of two classes of constraints, effector and task. We examined the effects of movement distance, target size, orientation of the movement in the workspace, and C-D gain on the kinematics of discrete pointing movements made with computer mouse. It was ...
Bahill A Terry - - 2007
The right-hand rules show the direction of the spin-induced deflection of baseball pitches: thus, they explain the movement of the fastball, curveball, slider and screwball. The direction of deflection is described by a pair of right-hand rules commonly used in science and engineering. Our new model for the magnitude of ...
Gutenkunst Ryan - - 2007
We use observed movement tracks of Atlantic bluefin tuna in the Gulf of Maine and mathematical modeling of this movement to identify possible resource patches. We infer bounds on the overall sizes and distribution of such patches, even though they are difficult to quantify by direct observation in situ. To ...
Dounskaia Natalia - - 2007
It has been observed that the motion of the arm end-point (the hand, fingertip or the tip of a pen) is characterized by a number of regularities (kinematic invariants). Trajectory is usually straight, and the velocity profile has a bell shape during point-to-point movements. During drawing movements, a two-thirds power ...
Bernier Pierre-Michel - - 2006
This study sought to determine whether intact proprioception is required to adapt to a novel kinematic environment. We compared adaptation with a rotated visual feedback between a deafferented patient and healthy participants. They performed reaching movements towards visible targets while vision of the cursor was rotated by 30 degrees with ...
Bourdin C - - 2006
In everyday life, because of unexpected mechanical perturbation applied to the hand or to the whole body, hand movements may become suddenly inaccurate. With prolonged exposure to the perturbation, trajectories slowly recover their normal accuracy, which is the mark of motor adaptation. However, full development of this adaptive process in ...
Carey James R - - 2006
The authors used functional magnetic resonance imaging to explore whether the primary motor area (M1) serves a processing role in a finger-movement tracking task, emphasizing attention to accuracy, beyond its execution role of simple movements, with no attention to accuracy. Twenty healthy subjects performed alternating conditions: Rest, involving no finger ...
Rapp David N - - 2006
Traditional research on situation models has examined the accessibility of locations and objects during narrative experiences. These studies have described a ubiquitous gradient effect: Spatial locations and objects in reader focus are more accessible than locations farther from this focus, with accessibility decreasing as a function of distance. How might ...
Jonas M M Department of Neurology, University Medical Center Hamburg Eppendorf, Martinistr. 52, 20246, Hamburg, Germany. - - 2007
Behavioural advantages for imitation of human movements over movements instructed by other visual stimuli are attributed to an 'action observation-execution matching' (AOEM) mechanism. Here, we demonstrate that priming/exogenous cueing with a videotaped finger movement stimulus (S1) produces specific congruency effects in reaction times (RTs) of imitative responses to a target ...
Sato Hiroki - - 2006
We have developed a wavelet-based method of detecting body-movement artifacts in optical topography (OT) signals. Although OT, which is a noninvasive imaging technique for measuring hemodynamic response related to brain activation, is particularly useful for studying infants, the signals occasionally contain undesirable artifacts caused by body movements, so data corrupted ...
Hwang Ing-Shiou - - 2006
In light of the interplay between limb oscillatory outputs and the outcome performance of movement effectors, this study was undertaken to investigate neuromotor control in the upper limb during position tracking and posture holding. Sixteen volunteers conducted a postural pointing task and two index tracking maneuvers at 0.3 and 0.6 ...
Spencer Rebecca M C - - 2006
Constraints underlying bimanual coordination have traditionally been explained by dynamic interactions between the effectors. However, the present experiments demonstrate that a fundamental constraint on bimanual performance is the manner in which task goals are represented. In Experiment 1, participants vocalized during in-phase and anti-phase bimanual movements. As expected, most participants ...
Puca Rosa Maria - - 2006
The present research is based on the assumption that people differ in their responsiveness to incentives and threats. In two experiments we examined whether the trait corresponding to the responsiveness to threats (avoidance motive) and the trait corresponding to the responsiveness to incentives (approach motive) influence voluntary motor behavior toward ...
Hirai Hiroaki - - 2006
This paper describes the hierarchical architecture for a rhythmic coordination between robots, which suits juggling-like tasks involving sensory-motor coordination. The authors' approach, which is interpreted as a "bidirectional weak coupling" to the environment, does not require either the environmental model or continuously monitoring the environment but can adapt the robots ...
Torres Elizabeth - - 2006
Is the movement duration time known before we move? To answer this question, a new experimental paradigm is introduced that for the first time monitors the acquisition of a new motor skill in rhesus monkeys. Straight reaches were interleaved with reaches around physical obstacles that elicited a different path geometry. ...
Foisy Martin M Neurological Science Research Center, Department of Physiology, Rehabilitation Institute of Montreal, University of Montreal and Center for Interdisciplinary Research Studies in Rehabilitation CRIR, 6300 Darlington Ave, Montreal, QC, - - 2006
We addressed the fundamental questions of which variables underlie the control of arm movement and how they are stored in motor memory, reproduced and modified in the process of adaptation to changing load conditions. Such variables are defined differently in two major theories of motor control (internal models and threshold ...
Heuer Herbert - - 2006
Temporal and spatial movement characteristics are often seen as controlled separately, although they are not independent. Even in the case of simple oscillations mean frequency and mean amplitude covary when one or the other is changed intentionally. The present experiment revealed that in rapid finger oscillations there is also a ...
Bortoletto Marta - - 2006
The present study investigated the role of pre-motion positivity in movement initiation and the reason why it is not reliably detectable in every study participant. Nineteen right-handed participants performed self-initiated simple movements of the right index finger and mouth while electroencephalography activity was recorded. Most of the participants showed a ...
Pinkston Jonathan W - - 2006
Recent research has demonstrated that avian species may show an enhanced locomotor response to repeated drug exposure, a phenomenon called sensitization. Further research in this domain is warranted as such results not only establish the generality of previous findings, but may lend to a better understanding of sensitization in general. ...
Begon M - - 2007
Determination of the hip joint centre (HJC) using a functional approach requires access to the kinematics of various body postures. The present study aimed to determine the combined impact of the nature of the movement, its type and the number of cycles, on the accuracy of HJC estimation. Kinematics noise ...
O'Leary John G - - 2006
Local field potentials (LFPs) recorded from primary motor cortex (MI) have been shown to be tuned to the direction of visually guided reaching movements, but MI LFPs have not been shown to be tuned to the direction of an upcoming movement during the delay period that precedes movement in an ...
Wallace Douglas G - - 2006
Rat exploration is an organized series of trips. Each exploratory trip involves an outward tour from the refuge followed by a return to the refuge. A tour consists of a sequence of progressions with variable direction and speed concatenated by stops, whereas the return consists of a single direct progression. ...
Wallace Douglas G - - 2006
Rat exploration is an organized series of trips. Each exploratory trip involves an outward tour from the refuge followed by a return to the refuge. A tour consists of a sequence of progressions with variable direction and speed concatenated by stops, whereas the return consists of a single direct progression. ...
Sylvestre Pierre A - - 2006
Simple activities like picking up the morning newspaper or catching a ball require finely coordinated movements of multiple body segments. How our brain readily achieves such kinematically complex yet remarkably precise multijoint movements remains a fundamental and unresolved question in neuroscience. Many prevailing theoretical frameworks ensure multijoint coordination by means ...
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