Sensory reweighting of proprioceptive information of the left and right leg during human balance control

2012 ◽  
Vol 108 (4) ◽  
pp. 1138-1148 ◽  
Author(s):  
J. H. Pasma ◽  
T. A. Boonstra ◽  
S. F. Campfens ◽  
A. C. Schouten ◽  
H. Van der Kooij
Keyword(s):  
Visual Information ◽  
Balance Control ◽  
The Other ◽  
Reliable Information ◽  
Proprioceptive Information ◽  
Sensory Reweighting ◽  
Perturbation Amplitude ◽  
Eyes Closed ◽  
Platform Translation ◽  
Support Surfaces

To keep balance, information from different sensory systems is integrated to generate corrective torques. Current literature suggests that this information is combined according to the sensory reweighting hypothesis, i.e., more reliable information is weighted more strongly than less reliable information. In this approach, no distinction has been made between the contributions of both legs. In this study, we investigated how proprioceptive information from both legs is combined to maintain upright stance. Healthy subjects maintained balance with eyes closed while proprioceptive information of each leg was perturbed independently by continuous rotations of the support surfaces (SS) and the human body by platform translation. Two conditions were tested: perturbation amplitude of one SS was increased over trials while the other SS 1) did not move or 2) was perturbed with constant amplitude. With the use of system identification techniques, the response of the ankle torques to the perturbation amplitudes (i.e., the torque sensitivity functions) was determined and how much each leg contributed to stabilize stance (i.e., stabilizing mechanisms) was estimated. Increased amplitude of one SS resulted in a decreased torque sensitivity. The torque sensitivity to the constant perturbed SS showed no significant differences. The properties of the stabilizing mechanisms remained constant during perturbations of each SS. This study demonstrates that proprioceptive information from each leg is weighted independently and that the weight decreases with perturbation amplitude. Weighting of proprioceptive information of one leg has no influence on the weight of the proprioceptive information of the other leg. According to the sensory reweighting hypothesis, vestibular information must be up-weighted, because closing the eyes eliminates visual information.

Adaptation to Visual Rearrangement: Role of Sensory Discordance

1977 ◽  
Vol 29 (2) ◽  
pp. 237-244 ◽  
Author(s):  
Jennifer A. Mather ◽  
James R. Lackner
Keyword(s):  
Point Source ◽  
Visual Information ◽  
Visual Stimulation ◽  
The Other ◽  
Proprioceptive Information ◽  
Voluntary Movements ◽  
Limb Position ◽  
Reflex Movement ◽  
Sensory Discordance

The relative contributions of proprioceptive and efferent information in eliciting adaptation to visual rearrangement were studied under two conditions of visual stimulation. Subjects permitted sight of their forearm under normal room illumination showed significant adaptation when the forearm was (a) moved up and down under the action of tonic vibration reflexes, (b) voluntarily moved through the same trajectory at the same pace, (c) viewed while still, and (d) viewed while the margins of the elbow were vibrated. The reflex movement condition elicited significantly greater adaptation than the other conditions. Subjects allowed only sight of a point source of light attached to their hand showed significant adaptation when the forearm was (a) reflexly moved, (b) voluntarily moved through the same trajectory at the same rate, (c) passively moved, (d) still, and (e) vibrated while still. Less adaptation occurred as the amount of proprioceptive information about limb position was decreased. The adaptation elicited by voluntary movements of the forearm and by reflex movements did not differ significantly. It is concluded that corollary-discharge signals may not be crucial in adaptation to visual rearrangement; a more important factor appears to be discordance between proprioceptive and visual information.

scholarly journals Sensory Reweighting in Targeted Reaching: Effects of Conscious Effort, Error History, and Target Salience

2010 ◽  
Vol 103 (1) ◽  
pp. 206-217 ◽  
Author(s):  
Hannah J. Block ◽  
Amy J. Bastian
Keyword(s):  
Minimum Variance ◽  
The Body ◽  
The Other ◽  
Proprioceptive Information ◽  
Sensory Reweighting ◽  
Sensorimotor Processing ◽  
Important Principle ◽  
Conscious Effort ◽  
Visual Error ◽  
The Brain

When both visual and proprioceptive information are available about the position of a part of the body, the brain weights and combines these sources to form a single estimate, often modeled by minimum variance integration. These weights are known to vary with different circumstances, but the type of information causing the brain to change weights (reweight) is unknown. Here we studied reweighting in the context of estimating the position of a hand for the purpose of reaching it with the other hand. Subjects reached to visual (V), proprioceptive (P), or combined (VP) targets in a virtual reality setup. We calculated weights for vision and proprioception by comparing endpoints on VP reaches with endpoints on P and V reaches. Endpoint visual feedback was manipulated to control completely for the error history seen by subjects. In different experiments, we manipulated target salience, conscious effort, or statistics of the visual error history to see if these cues could cause reweighting. Most subjects could reweight strongly by conscious effort. Changes in target salience reliably caused reweighting, but seen error history alone did not. We also found that experimental weights can be predicted by minimizing the variance of visual and proprioceptive estimates, supporting the idea that minimum variance integration is an important principle of sensorimotor processing.

scholarly journals Integration of Proprioceptive and Visual Position-Information: An Experimentally Supported Model

1999 ◽  
Vol 81 (3) ◽  
pp. 1355-1364 ◽  
Author(s):  
Robert J. van Beers ◽  
Anne C. Sittig ◽  
Jan J. Denier van der Gon
Keyword(s):  
Visual Information ◽  
The Body ◽  
The Other ◽  
Proprioceptive Information ◽  
Position Information ◽  
Left Hand ◽  
The Mean ◽  
The Right ◽  
Variable Errors ◽  
Available Information

Integration of proprioceptive and visual position-information: an experimentally supported model. To localize one’s hand, i.e., to find out its position with respect to the body, humans may use proprioceptive information or visual information or both. It is still not known how the CNS combines simultaneous proprioceptive and visual information. In this study, we investigate in what position in a horizontal plane a hand is localized on the basis of simultaneous proprioceptive and visual information and compare this to the positions in which it is localized on the basis of proprioception only and vision only. Seated at a table, subjects matched target positions on the table top with their unseen left hand under the table. The experiment consisted of three series. In each of these series, the target positions were presented in three conditions: by vision only, by proprioception only, or by both vision and proprioception. In one of the three series, the visual information was veridical. In the other two, it was modified by prisms that displaced the visual field to the left and to the right, respectively. The results show that the mean of the positions indicated in the condition with both vision and proprioception generally lies off the straight line through the means of the other two conditions. In most cases the mean lies on the side predicted by a model describing the integration of multisensory information. According to this model, the visual information and the proprioceptive information are weighted with direction-dependent weights, the weights being related to the direction-dependent precision of the information in such a way that the available information is used very efficiently. Because the proposed model also can explain the unexpectedly small sizes of the variable errors in the localization of a seen hand that were reported earlier, there is strong evidence to support this model. The results imply that the CNS has knowledge about the direction-dependent precision of the proprioceptive and visual information.

scholarly journals Compliant support surfaces affect sensory reweighting during balance control

2017 ◽  
Vol 53 ◽  
pp. 241-247 ◽  
Author(s):  
I.M. Schut ◽  
D. Engelhart ◽  
J.H. Pasma ◽  
R.G.K.M. Aarts ◽  
A.C. Schouten
Keyword(s):  
Balance Control ◽  
Sensory Reweighting ◽  
Support Surfaces

scholarly journals POSTURAL SWAY IN LOWER EXTREMITY AMPUTEES AND OLDER ADULTS MAY SUGGEST INCREASED FALL RISK IN AMPUTEES

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Hamid Bateni
Keyword(s):  
Older Adults ◽  
Young Adults ◽  
Lower Extremity ◽  
Frequency Domain ◽  
Visual Information ◽  
Fall Risk ◽  
Postural Sway ◽  
Proprioceptive Information ◽  
Eyes Closed ◽  
Eyes Open

BACKGROUND: Falls can be detrimental to overall health and quality of life for lower extremity amputees. Most previous studies of postural steadiness focus on quantification of time series variables extracted from postural sway signals. While it has been suggested that frequency domain variables can provide more valuable information, few current studies have evaluated postural sway in amputees using frequency domain variables. OBJECTIVE: To determine time and frequency domain variables of postural sway among lower extremity amputees vs. healthy young and older adult controls. METHODOLOGY: Participants were assigned to 3 groups:  lower extremity amputation (n=6), healthy young adults (n=10), and healthy older adults (n=10). Standing barefoot on a force platform, each individual completed 3 trials of each of 3 standing conditions: eyes open, eyes closed, and standing on a foam balance pad. Time and frequency domain variables of postural sway were computed and analyzed. RESULTS: Comparison of older adults, younger adults, and amputees on the three conditions of standing eyes open, eyes closed, and on foam revealed significant differences between groups. Mean mediolateral (ML) sway distance from the center of pressure (COP), total excursions and sway velocity was significantly higher for amputees and older adults when compared to young adults (p<0.05). Furthermore, power of sway signal was substantially lower for both amputees and older adults. When compared to that of older adults, postural steadiness of amputees was more affected by the eyes closed condition, whereas older adults’ was more affected when sensory and proprioceptive information was perturbed by standing on foam.  CONCLUSION: Our findings showed that fall risk is greater in amputees than in young adults without amputation. Additionally, amputees may rely more heavily on visual information than proprioceptive information for balance, in contrast to older and young adults without amputation.  Layman's Abstract Falls can be detrimental to overall health and quality of life for lower extremity amputees. We evaluated postural sway and concluded that amputees have an increased fall risk and may rely more heavily on visual information for balance than do individuals without amputation. Article PDF Link:https://jps.library.utoronto.ca/index.php/cpoj/article/view/33804/26600 How To Cite: Bateni H. Postural sway in lower extremity amputees and older adults may suggest increased fall risk in amputees. Canadian Prosthetics & Orthotics Journal. 2020;Volume 3, Issue 2, No.4. https://doi.org/10.33137/cpoj.v3i2.33804 Corresponding Author: Hamid Bateni, PhD Physical Therapy Program, School of Allied Health and Communicative Disorders, Northern Illinois University, DeKalb, Illinois, USA.E-mail: [email protected]: https://orcid.org/0000-0001-9083-1817

scholarly journals Contribution of Sensorimotor Integration to Spinal Stabilization in Humans

2009 ◽  
Vol 102 (1) ◽  
pp. 496-512 ◽  
Author(s):  
Adam D. Goodworth ◽  
Robert J. Peterka
Keyword(s):  
Visual Information ◽  
Time Course ◽  
Visual Orientation ◽  
Model Parameters ◽  
Proprioceptive Information ◽  
Time Lags ◽  
Impulse Response Functions ◽  
Response Functions ◽  
Stimulus Amplitude ◽  
Eyes Closed

The control of upper body (UB) orientation relative to the pelvis in the frontal plane was characterized by analyzing responses to external perturbations consisting of continuous pelvis tilts (eyes open [EO] and eyes closed [EC]) and visual surround tilts (EO) at various amplitudes. Lateral sway of the lower body was prevented on all tests. UB sway was analyzed by calculating impulse–response functions (IRFs) and frequency–response functions (FRFs) from 0.023 to 10.3 Hz for pelvis tilt tests and FRFs from 0.041 to 1.5 Hz for visual tests. For pelvis tilt tests, differences between FRFs were limited to frequencies <3 Hz and were dependent on stimulus amplitude. IRFs were nearly identical across all pelvis tilt tests for the first 0.2 s, but showed amplitude-dependent changes in their time course at longer time lags. The availability of visual orientation cues (EO vs. EC) had only a small effect on the UB sway during pelvis tilt tests. This small effect of vision was consistent with the small UB sway evoked on visual tilt tests. Experimental results were interpreted using a feedback model of UB orientation control that included time-delayed sensory integration, short-latency reflexive mechanisms, and intrinsic biomechanical properties of the UB. Variation in model parameters indicated that subjects shifted toward reliance on vestibular information and away from proprioceptive information as pelvis tilt amplitudes increased. For visual tilt stimuli, model parameters indicated that subjects shifted toward reliance on vestibular and proprioceptive information and away from visual information as the stimulus amplitude increased.

scholarly journals Sensory feedback and coordinating asymmetrical landing in toads

2016 ◽  
Vol 12 (6) ◽  
pp. 20160196 ◽  
Author(s):  
S. M. Cox ◽  
Gary B. Gillis
Keyword(s):  
Visual Feedback ◽  
Muscle Activity ◽  
Visual Information ◽  
Sensory Feedback ◽  
Sensory Input ◽  
Joint Angle ◽  
The Other ◽  
Proprioceptive Information ◽  
Conflicting Information

Coordinated landing requires anticipating the timing and magnitude of impact, which in turn requires sensory input. To better understand how cane toads, well known for coordinated landing, prioritize visual versus vestibular feedback during hopping, we recorded forelimb joint angle patterns and electromyographic data from five animals hopping under two conditions that were designed to force animals to land with one forelimb well before the other. In one condition, landing asymmetry was due to mid-air rolling, created by an unstable takeoff surface. In this condition, visual, vestibular and proprioceptive information could be used to predict asymmetric landing. In the other, animals took off normally, but landed asymmetrically because of a sloped landing surface. In this condition, sensory feedback provided conflicting information, and only visual feedback could appropriately predict the asymmetrical landing. During the roll treatment, when all sensory feedback could be used to predict an asymmetrical landing, pre-landing forelimb muscle activity and movement began earlier in the limb that landed first. However, no such asymmetries in forelimb preparation were apparent during hops onto sloped landings when only visual information could be used to predict landing asymmetry. These data suggest that toads prioritize vestibular or proprioceptive information over visual feedback to coordinate landing.

scholarly journals Age-Related Changes in Postural Responses to Backward Platform Translation

2012 ◽  
pp. 331-335 ◽  
Author(s):  
Z. HALICKÁ ◽  
J. LOBOTKOVÁ ◽  
D. BZDÚŠKOVÁ ◽  
F. HLAVAČKA
Keyword(s):  
Balance Control ◽  
Tibialis Anterior Muscle ◽  
Emg Activity ◽  
Eyes Closed ◽  
Healthy Elderly ◽  
Age Related ◽  
Postural Responses ◽  
Co Activation ◽  
Platform Translation ◽  
Age Related Changes

The aim of the study was to investigate age-related changes in postural responses to platform translation with 3 various velocities. We focused on the influence of linear velocity using the smoothed profile of platform acceleration (till 100 cm.s−2). Eleven healthy young (20-31 years) and eleven healthy elderly (65-76 years) subjects were examined. The subjects stood on the force platform with their eyes closed. Each trial (lasting for 8 sec) with different velocity (10, 15, 20 cm.s−1) of 20 cm backward platform translation was repeated 4 times. We have recorded displacements of the centre of pressure (CoP) and the EMG activity of gastrocnemius muscle (GS) and tibialis anterior muscle (TA). The results showed increased maximal values of CoP responses to the platform translation. There was also observed a scaling delay of CoP responses to platform translation with different velocities in elderly. The EMG activity of GS muscle during backward platform translation was of about similar shape in both groups during the slowest platform velocity, but it increased depending on rising velocity. EMG activity of TA was not related to the platform velocity. Early parts of postural responses showed significant co-activation of TA and GS muscles of elderly. It is likely that elderly increased body stiffening in order to help their further balance control.

Reproduction of Object Shape is More Accurate without the Continued Availability of Visual Information

Perception ◽  
1998 ◽  
Vol 27 (1) ◽  
pp. 69-86 ◽  
Author(s):  
Michel-Ange Amorim ◽  
Jack M Loomis ◽  
Sergio S Fukusima
Keyword(s):  
Visual Information ◽  
Internal Representation ◽  
Stimulus Configuration ◽  
The Other ◽  
Additional Information ◽  
Distant Stimulus ◽  
Perspective Change ◽  
Visual Presence ◽  
Viewpoint Change ◽  
Actual Change

An unfamiliar configuration lying in depth and viewed from a distance is typically seen as foreshortened. The hypothesis motivating this research was that a change in an observer's viewpoint even when the configuration is no longer visible induces an imaginal updating of the internal representation and thus reduces the degree of foreshortening. In experiment 1, observers attempted to reproduce configurations defined by three small glowing balls on a table 2 m distant under conditions of darkness following ‘viewpoint change’ instructions. In one condition, observers reproduced the continuously visible configuration using three other glowing balls on a nearer table while imagining standing at the distant table. In the other condition, observers viewed the configuration, it was then removed, and they walked in darkness to the far table and reproduced the configuration. Even though the observers received no additional information about the stimulus configuration in walking to the table, they were more accurate (less foreshortening) than in the other condition. In experiment 2, observers reproduced distant configurations on a nearer table more accurately when doing so from memory than when doing so while viewing the distant stimulus configuration. In experiment 3, observers performed both the real and imagined perspective change after memorizing the remote configuration. The results of the three experiments indicate that the continued visual presence of the target configuration impedes imaginary perspective-change performance and that an actual change in viewpoint does not increase reproduction accuracy substantially over that obtained with an imagined change in viewpoint.

Evoked Potentials by Letters in Printed and Script Forms

1984 ◽  
Vol 59 (1) ◽  
pp. 227-232 ◽  
Author(s):  
Luciano Mecacci ◽  
Dario Salmaso
Keyword(s):  
Information Processing ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Adult Male ◽  
Visual Information ◽  
The Other ◽  
Behavioral Data ◽  
Evoked Responses ◽  
Amplitude Component ◽  
Male Subjects

Visual evoked potentials were recorded for 6 adult male subjects in response to single vowels and consonants in printed and script forms. Analysis showed the vowels in the printed form to have evoked responses with shorter latency (component P1 at about 133 msec.) and larger amplitude (component P1-N1) than the other letter-typeface combinations. No hemispheric asymmetries were found. The results partially agree with the behavioral data on the visual information-processing of letters.

Sign in / Sign up

Export Citation Format

Share Document