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Rabin Ely E New York College of Osteopathic Medicine of New York Institute of Technology, Northern Boulevard, Old Westbury, NY 11568-8000, USA. - - 2006
Contact of the index finger with a stable surface greatly attenuates postural sway in blindfolded subjects. The time course of postural stabilization was measured after subjects made finger contact with a surface. Subjects (n=12) were tested standing in a heel-to-toe stance in 25 s duration trials. The subject stood with ...
Cenciarini Massimo - - 2006
Humans maintain stable stance in a wide variety of environments. This robust behavior is thought to involve sensory reweighting whereby the nervous system adjusts the relative contribution of sensory sources used to control stance depending on environmental conditions. Based on prior experimental and modeling results, we developed a specific quantitative ...
Hwang Ing-Shiou - - 2006
An experiment was conducted to compare the effects of bilateral and unilateral stance on postural fluctuations and intralimb coordination during active balance control. Fifteen participants stood bilaterally and unilaterally while conducting a pointing task with an outstretched arm. Excursion of center of foot pressure (CoP) and limb movements were recorded ...
Musolino Mark C - - 2006
The present study investigated the effect of optic flow periodicity on postural sway. Head and center-of-pressure (COP) displacements in response to an oscillating full-field bullseye-and-checkerboard pattern were recorded in six healthy adults. Scene movement was driven by one of five signals: (1) 0.1 Hz sinusoid, (2) 0.3 Hz sinusoid, (3) ...
Chen J J - - 2006
Legs of sprawled-posture, quadrupedal trotting geckos (Hemidactylus garnotii) each functioned differently during constant average-speed locomotion. The center of mass decelerated in the first half of a step and accelerated in the second half, as if geckos were bouncing in fore-aft and side-to-side directions. Forelegs decelerated the center of mass only ...
Virk Sumandeep S Dept. of Electr. & Comput. Eng., Ryerson Univ., Toronto, Ont., Canada. - - 2006
Maintaining balance under all conditions is an absolute requirement for humans. Orientation in space and balance maintenance requires inputs from the vestibular, the visual, the proprioceptive and the somatosensory systems. All the cues coming from these systems are integrated by the central nervous system (CNS) to employ different strategies for ...
Cikajlo Imre I Inst. for Rehabilitation, Ljubljana. - - 2006
The paper presents a novel normative based method and apparatus for objective assessment of postural responses during unexpected perturbation in clinical environment. A modified standing frame (based on BalanceTrainer) for standing-balance training in a fall-safe balancing environment equipped with electrical actuators to provide unexpected perturbations in eight directions during quiet ...
Normand Matthew P - - 2006
The current study evaluated the effects of a stimulus-stimulus pairing procedure intended to increase spontaneous vocalizations of a young child diagnosed with autism. A multiple-baseline design across two target phonemes was used to evaluate the effects of the pairing procedure on the frequency of phonemes uttered by the participant. Data ...
Piirtola Maarit M Department of Family Medicine, University of Turku, Turku, Finland. - - 2006
Poor postural balance is one of the major risk factors for falling. A great number of reports have analyzed the risk factors and predictors of falls but the results have for the most part been unclear and partly contradictory. Objective data on these matters are thus urgently needed. The force ...
Ebersole Marissa L - - 2006
OBJECTIVE: The aim of this work was to quantify the interrater reliability of a set of scales that assess repetition, posture, and force as used on site when examining industrial work. BACKGROUND: Interrater reliability of observational assessment methods can vary depending on the definition of the methods and situations in ...
Peterka Robert J - - 2006
We present a quantitative method for characterizing the effectiveness of a balance prosthesis based on tactile vibrators. The balance prosthesis used an array of 12 tactile vibrators (tactors) placed on the anterior and posterior surfaces of the torso to provide body orientation feedback related to the angular position and velocity ...
Bhatt T T Department of Physical Therapy, University of Illinois at Chicago, 1919 West Taylor St., Room 426 M/C 898, Chicago, IL 60612, - - 2006
The properties of adaptation within the locomotor and balance control systems directed towards improving one's recovery strategy for fall prevention are not well understood. The purpose of this study was to examine adaptive control of gait stability to repeated slip exposure leading to a reduction in backward loss of balance ...
Dickstein Ruth - - 2005
Unilateral light fingertip touch of a stationary object has a significant stabilizing effect on postural sway during stance. The purpose of this study was to find out if this effect is enhanced by bilateral light touch of parallel stationary objects. The postural sway of 54 healthy subjects was tested in ...
Paillard Thierry - - 2005
In competitions, judokas tend to have a predominant direction of fall: forwards or backwards. A relationship was hypothesized between the direction of fall and certain parameters of the judokas' postural activities. 20 judokas, 16 to 19 yr. old (17.7 +/- 0.4 yr.), had practised judo for at least seven years. ...
Maurer C C Neurological University Clinic, Neurozentrum Breisacher Str. 64, 79106, Freiburg, Germany. - - 2006
The interaction of different orientation senses contributing to posture control is not well understood. We therefore performed experiments in which we measured the postural responses of normal subjects and vestibular loss patients during perturbation of their stance. Subjects stood on a motion platform with their eyes closed and auditory cues ...
Simoneau Martin M Faculté de Médecine, Division de kinésiologie, Université Laval, PEPS, G1K 7P4, Québec, QC, Canada. - - 2006
Balance control is influenced by the availability and integrity of sensory inputs as well as the ability of the balance control mechanisms to tailor the corrective action to the gravitational torque. In this study, to challenge balance control, visual and ankle proprioceptive information were perturbed (eyes closed and/or tendon vibration). ...
Overney Leila S - - 2005
There is growing evidence that the visual processing of human body stimuli is particular and distinct from that of other objects. This is due to implicit knowledge of anatomical and biomechanical constraints of the human body. The question arises whether body stimuli in which biomechanical constraints are violated are processed ...
Vuillerme Nicolas N Laboratoire TIMC-IMAG, Faculté de Médecine, UMR CNRS 5525, Equipe AFIRM, 38706, La Tronche cédex, France. - - 2006
The purpose of the present experiment was to investigate whether and how using a light fingertip touch for postural control during quiet standing requires additional attentional demands. Nine young healthy university students were asked to respond as rapidly as possible to an unpredictable auditory stimulus while maintaining stable seated and ...
Bleuse Séverine - - 2006
Aging is frequently accompanied by a deterioration in postural control. Accordingly, the elderly adopt postural strategies in order to maintain balance. The purpose of this study was to compare anticipatory postural adjustments in (healthy) 10 young and 10 elderly subjects using electromyography (EMG) and biomechanical parameters. While standing on a ...
Dickstein Ruth - - 2006
The purpose of this study was to examine the effect of Transcutaneous Electrical Nerve Stimulation (TENS) applied to the posterior aspect of the legs, on postural sway during stance. Thirty healthy subjects were tested while standing on a force platform under four stimulation conditions: no TENS, bilateral TENS, and unilateral ...
Berencsi Andrea - - 2005
Three experiments were conducted to investigate the role of central and peripheral vision (CV and PV) in postural control. In Experiment 1, either the central or peripheral visual field were selectively stimulated using a circular random dot pattern that was either static or alternated at 5 Hz. Center of foot ...
Chow Daniel H K - - 2006
Concerns have been raised regarding the effect of carrying a backpack on adolescent posture and balance, but the effect of backpack loading combined with other factors affecting balance, such as adolescent idiopathic scoliosis (AIS), has not been determined. This study examines the effects of backpack load on the posture and ...
Maurer C C Neurological University Clinic, Breisacher Str. 64, 79106, Freiburg, Germany. - - 2006
A veridical internal notion of the kinematic state of the foot support is essential for postural control. The means by which this is obtained is still a matter of debate. We therefore measured the conscious perception of support tilt during transient anterior-posterior rotations of a motion platform in six healthy ...
Mergner T T Neurological University Clinic, Neurocenter, Breisacher Str. 64, 79106 Freiburg, Germany. - - 2005
The role of visual orientation cues for human control of upright stance is still not well understood. We, therefore, investigated stance control during motion of a visual scene as stimulus, varying the stimulus parameters and the contribution from other senses (vestibular and leg proprioceptive cues present or absent). Eight normal ...
Jacobs Jesse V JV Neurological Sciences Institute, Oregon Health & Science University, 505 NW 185th Avenue, Beaverton, Portland, OR 97006-3499, - - 2005
To determine the effects of the stooped posture of patients with Parkinson's disease (PD) on postural stability, we compared the kinetic, kinematic, and electromyographic responses of seven subjects with PD and 11 control subjects to eight directions of surface translations. Control subjects were studied in an upright posture and in ...
Kobayashi Kenji - - 2005
CONCLUSIONS: Postural responses differed according to the stimulus direction, i.e. vertical visual stimulation induced head rather than trunk displacements. Accordingly, it could be that center of foot pressure (COP) responses tended to underestimate the postural sway during visual stimulation. OBJECTIVES: To investigate head and body sway in response to vertical ...
Paloski William H - - 2006
To better understand the effects of varying head movement frequencies on human balance control, 12 healthy adult humans were studied during static and dynamic (0.14, 0.33, 0.6 Hz) head tilts of +/- 30 degrees in the pitch and roll planes. Postural sway was measured during upright stance with eyes closed ...
Hughey Lucinda K LK School of Physical & Occupational Therapy, McGill University, 3654 Prom. Sir William Osler, Montreal, Quebec, Canada, H3G - - 2005
The aim of the present study was to investigate the relationship between proactive and reactive components of postural control. We contrasted the kinematic and electromyographic (EMG) responses to multidirectional voluntary leg lifts with those elicited by unexpected surface tilts. In particular, we addressed the role of trunk stabilization following either ...
Rougier P P Laboratoire de Modélisation des Activités Sportives, UFR CISM, Université de Savoie, Campus Scientifique de Savoie-Technolac, 73 376 Le Bourget du Lac, France. - - 2005
Fourteen healthy adults were tested to assess the potential influence on stance maintenance of two parts of the visual feedback technique (display scale and time delay). The task consisted in their keeping a spot on the screen representing their center of pressure, CoP (i.e. successive points of application of the ...
Prioli Ana Caroline - - 2005
BACKGROUND: Aging is characterized by a decline in the postural control performance, which is based on a coherent and stable coupling between sensory information and motor action. Therefore, changes in postural control in elderlies can be related to changes in this coupling. In addition, it has been observed that physical ...
Shin Yong-June - - 2005
In this paper, the effects of visual feedback and aging on postural sway systems and signals are investigated by analyzing the transient phase difference between "input" and "output" which correspond to center of pressure (COP) and center of mass (COM), respectively. In order to analyze the transient phase difference characteristics ...
Duarte Marcos - - 2005
We investigated the speed and accuracy of fast voluntary movements performed by the whole body during standing. Adults stood on a force plate and performed rhythmic postural movements generating fore and back displacements of the center of pressure (shown as online visual feedback). We observed that for the same target ...
Pedrocchi Alessandra - - 2005
This study deals with the quantitative assessment of exchanged forces and torques at the restraint point during whole body posture perturbation movements in long-term microgravity. The work was based on the results of a previous study focused on trunk bending protocol, which suggested that the minimization of the torques exchanged ...
Vuillerme Nicolas - - 2005
The purpose of the present experiment was to investigate whether and how the head extended posture, commonly encountered in many routine activities, affects undisturbed upright stance control mechanisms in humans. Sixteen young healthy adults stood feet together, with their eyes closed and were asked to sway as little as possible ...
Cote Karen P - - 2005
Context: The foot is the most distal segment in the lower extremity chain and represents a relatively small base of support on which the body maintains balance (particularly in single-leg stance). Although it seems reasonable that even minor biomechanical alterations in the support surface may influence postural-control strategies, the implications ...
Freitas Sandra M S F - - 2005
BACKGROUND: Postural sway during quiet standing reduces when somatosensorial information is provided by an active or passive "light touch" of different body parts with a surface. The contact of the safety harness with the body could induce a similar effect, leading to an undesirable side effect in the balance evaluation. ...
Slobounov S - - 2005
OBJECTIVE: It was our primary objective to provide evidence supporting the existence of neural detectors for postural instability that could trigger the compensatory adjustments to avoid falls. METHODS: Twelve young healthy subjects performed self-initiated oscillatory and discrete postural movements in the anterior-posterior (AP) directions with maximal range of motion predominantly ...
Vuillerme Nicolas - - 2005
The purpose of the present experiment was to investigate the effects of cervical muscular fatigue on postural control during quiet standing under different conditions of reliability and/or availability of somatosensory inputs from the plantar soles and the ankles and visual information. To this aim, 14 young healthy adults were asked ...
Fushiki Hiroaki - - 2005
CONCLUSION: Our results indicate that the illusion of self-motion is a significant factor leading to spatial disorientation. OBJECTIVE: Under normal circumstances, self-motion is perceived in response to motion of the head and body. However, under certain conditions, such as virtual reality environments, visually induced self-motion can be perceived even though ...
Bacsi Ann M AM Institute of Neurological Sciences and UNSW Clinical School, Prince of Wales Hospital, Randwick, 2031 Sydney, NSW, - - 2005
Vestibular signals are known to have an important role in stance under specific conditions. Potentially these effects could be modulated by vestibular reflexes or by voluntary responses to perceived vestibular signals. Our preliminary aim was to confirm that vestibulospinal reflexes change in parallel with sway under different postural conditions, and ...
Anderson Kenneth - - 2005
The most predominant literature regarding balance has emphasised the physiological mechanisms controlling stability. Topics range from extrinsic factors (environment) to intrinsic factors (i.e. muscle coordination, vestibular response). Balance is achieved through an interaction of central anticipatory and reflexive actions as well as the active and passive restraints imposed by the ...
Fujisawa N - - 2005
Control of the standing posture of humans involves at least two distinct modes of operation to restore the body balance in the sagittal plane: the ankle strategy and the hip strategy. The objective of the study was to estimate the contribution of vestibular, visual and somatosensory feedbacks to these distinct ...
Loeb Gerald G Member, IEEE, Alfred Mann Institute for Biomedical Engineering at the University of Southern California, Los Angeles, CA, 90089-1112, phone: 213-821-1112, fax: 213-821-1120, e-mails: gloeb@usc.edu and - - 2005
Kinesthesia is a sense of body posture and motion that arises from the interactions among the musculoskeletal system, a rich set of biological proprioceptors and the sensorimotor nervous system that mediates between them. This paper describes implantable sensor modalities to replace normal proprioceptors in feedback control. They can be packaged ...
Eriksson Lars - - 2005
Postural responses were utilized as measures of the effectiveness of a wide-angle visual flow display in determining perceived spatial orientation (SO). The general experimental setup included a 150 degrees x 34 degrees wide-field display showing flight over computer-generated ground with horizon. Simulated roll maneuvers on this display induced postural sway ...
Creath Robert R Department of Kinesiology, University of Maryland, College Park, MD 20742, - - 2005
When standing quietly, human upright stance is typically approximated as a single segment inverted pendulum. In contrast, investigations which perturb upright stance with support surface translations or visual driving stimuli have shown that the body behaves like a two-segment pendulum, displaying both in-phase and anti-phase patterns between the upper and ...
Gisolf Janneke - - 2004
INTRODUCTION: Cardiovascular response to fast posture change can be used to model individual orthostatic response under normal circumstances and after spaceflight. We set out to construct a computer-controlled tilt table suitable for repeated sinusoidal tilt motion as well as fast, single head-up tilt (HUT). The movement profile of the table ...
Bernard-Demanze L - - 2004
To assess the effects of changes in somesthetic plantar information on upright quiet stance, a rotary plantar massage was applied under the feet of healthy subjects for ten minutes. The controlling variable, the centre of pressure (CP) displacements, were recorded, before and after massage, through a force platform and decomposed ...
Genthon N - - 2005
Postural asymmetry in humans is generally associated with different pathologies. However, its specific influence on undisturbed upright stance is poorly understood. To evaluate its separate effects on each support, the centre of pressure (CP) displacements were recorded through two force platforms. In a second step, the complex resultant centre of ...
Asseman F - - 2005
This study analyzed the effect of head position and visual condition on the control of balance in handstand, a gymnastics posture that necessitates adaptation of sensory information processing. Five expert gymnasts participated. Centre of pressure trajectories and kinematics of different body segments were recorded. The gymnasts were instructed to maintain ...
Hatzitaki Vassilia - - 2005
The present study investigated how young and older individuals organize their posture in response to self-induced balance perturbations evoked by oscillatory single limb movements. Eleven old (70.1+/-4.3 years) and nine young (20.1+/-2.4 years) participants performed repeatedly for 5s hip flexion/extension movements using full range of motion and maximum velocity. Two-dimensional ...
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