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Økland, Finn; Norwegian Institute ...
Movements of and habitat utilisation by radio-tagged threespot tilapia (body length 25–50cm) were studied in the Upper Zambezi River between 23 November 2000 and 8 May 2001. Although utilising a relatively large stretch of river (average 5.4km) during the study period, the fish mainly stayed within defined home ranges, with ...
Khan Michael A - - 2008
The relation between reaction time and the number of elements in a response has been shown to depend on whether simple or choice RT paradigms are employed. The purpose of the present study was to investigate whether advance information about the number of elements is the critical factor mediating the ...
Hospod Valérie - - 2007
The aim of the present study was to test whether fusimotor control of human muscle spindle sensitivity changed when attention was selectively directed to the recognition of an imposed two-dimensional movement in the form of a written symbol. The unitary activities of 32 muscle spindle afferents (26 Ia, 6 II) ...
Huang Felix C - - 2007
The authors employed a virtual environment to investigate how humans use haptic and visual feedback in a simple, rhythmic object-manipulation task. The authors hypothesized that feedback would help participants identify the appropriate resonant frequency and perform online control adjustments. The 1st test was whether sensory feedback is needed at all; ...
George, Gerald James
The black drum, Pogonias cromis (Sciaenidae), is a molluscivorous, coastal/estuarine species, often associated with oyster reefs, that is sought in recreational and commercial fisheries. I used a radio-acoustic positioning system and an array of moored receivers to monitor movements of 34 black drum around oyster reefs in Barataria Bay, Louisiana ...
Flash Tamar - - 2007
Humans interact with their environment through sensory information and motor actions. These interactions may be understood via the underlying geometry of both perception and action. While the motor space is typically considered by default to be Euclidean, persistent behavioral observations point to a different underlying geometric structure. These observed regularities ...
Greiner Chieko - - 2007
Videotaping, direct observation, and biomechanical devices have been used to measure the wandering behavior of institutionalized people with dementia and to identify patterns of movement. Owing to technical limitations, the variability in movement patterns or the distance traveled could not be examined. The present study examined the feasibility of an ...
Schutte Anne R - - 2007
The timed-initiation paradigm developed by Ghez and colleagues (1997) has revealed two modes of motor planning: continuous and discrete. Continuous responding occurs when targets are separated by less than 60 degrees of spatial angle, and discrete responding occurs when targets are separated by greater than 60 degrees . Although these ...
Temprado J J - - 2007
The present work investigated the effects of spatial and neuromuscular constraints on the mean states and variability of interlimb coordination patterns performed in the para-sagittal plane of motion in a hand-held pendulum oscillation task. Nine right-handed students had to oscillate two pendulums through wrist adduction-abduction movements. Relative movement direction was ...
Foster Paul S - - 2007
BACKGROUND/HYPOTHESIS: The degree of attention directed to a stimulus and the presence of anisometric representations can alter the perception of the magnitude of a stimulus. We wanted to learn if normal right-handed subjects' estimates of distance traveled are influenced by the right-left direction or hemispace of movements. METHODS: We had ...
Haswgawa, Eiichi
The present study used six carps Cyprinus carpio,about 11cm in average total length,for investigating fish distribution in a funnel net and fish movement between two mountain-shaped nets which set on upper and lower sides or set on both sides. The most important effect to fish distribution in a funnel net ...
Ridderikhoff Arne A Institute for Fundamental and Clinical Human Movement Sciences (IFKB), Faculty of Human Movement Sciences, Vrije Universiteit, Van der Boechorststraat 9, 1081 BT, Amsterdam, The Netherlands. - - 2007
Although previous studies indicated that the stability properties of interlimb coordination largely result from the integrated timing of efferent signals to both limbs, they also depend on afference-based interactions. In the present study, we examined contributions of afference-based error corrections to rhythmic bimanual coordination using a kinesthetic tracking task. Furthermore, ...
Spencer Rebecca M C RM Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720-1650, USA. - - 2007
We have proposed that the stability of bimanual coordination is influenced by the complexity of the representation of the task goals. Here, we present two experiments to explore this hypothesis. First, we examined whether a temporal event structure is present in continuous movements by having participants vocalize while producing bimanual ...
Horn Robert R - - 2007
We compared the nature and rate of change in intra-limb coordination in participants who observed a video model (model) with those who practised based on verbal guidance only (control). Sixteen male novices threw a ball towards a target with maximal velocity using a back-handed, reverse baseball pitch. Participants in the ...
Bradshaw Corey J A - - 2007
Recent advances in telemetry technology have created a wealth of tracking data available for many animal species moving over spatial scales from tens of meters to tens of thousands of kilometers. Increasingly, such data sets are being used for quantitative movement analyses aimed at extracting fundamental biological signals such as ...
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 DH Department of Neurobiology and Behavior, The State University of New York at Stony Brook, Stony Brook, NY, - - 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 ...
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 ...
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 ...
Huang Jian J Dept. of Mechanical Engineering, Yokohama National University, Yokohama, Japan 240-8501. - - 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 R Institute of Sound and Vibration Research (ISVR), University of Southampton, Southampton, - - 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 ...
Pawar Tanmay T Department of Electrical Engineering, Indian Institute of Technology-Bombay, Mumbai, India. - - 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 ...
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 ...
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