Both stepping on a rotating platform and stepping while voluntarily turning around produce a post-effect consisting in inadvertent turning around while stepping-in-place eyes closed

Training subjects to step in place on a rotating platform while maintaining a fixed body orientation in space produces a posteffect consisting in inadvertent turning around while stepping in place eyes closed (podokinetic after-rotation, PKAR). We tested the hypothesis that voluntary turning around while stepping in place also produces a posteffect similar to PKAR. Sixteen subjects performed 12 min of voluntary turning while stepping around their vertical axis eyes closed and 12 min of stepping in place eyes open on the center of a platform rotating at 60°/s (pretests). Then, subjects continued stepping in place eyes closed for at least 10 min (posteffect). We recorded the positions of markers fixed to head, shoulder, and feet. The posteffect of voluntary turning shared all features of PKAR. Time decay of angular velocity, stepping cadence, head acceleration, and ratio of angular velocity after to angular velocity before were similar between both protocols. Both postrotations took place inadvertently. The posteffects are possibly dependent on the repeated voluntary contraction of leg and foot intrarotating pelvic muscles that rotate the trunk over the stance foot, a synergy common to both protocols. We propose that stepping in place and voluntary turning can be a scheme ancillary to the rotating platform for training body segment coordination in patients with impairment of turning synergies of various origin.

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The role of vestibular and somatosensory systems in intersegmental control of upright stance

Journal of Vestibular Research ◽

10.3233/ves-2008-18104 ◽

2008 ◽

Vol 18 (1) ◽

pp. 39-49 ◽

Cited By ~ 3

Author(s):

Rob Creath ◽

Tim Kiemel ◽

Fay Horak ◽

John J. Jeka

Keyword(s):

Support Surface ◽

Light Touch ◽

Upright Stance ◽

Rotating Platform ◽

Vestibular Loss ◽

Bilateral Vestibular Loss ◽

Eyes Closed ◽

Intersegmental Dynamics ◽

Somatosensory Information ◽

Leg Coordination

Upright stance was perturbed using sinusoidal platform rotations to see how vestibular and somatosensory information are used to control segment and intersegmental dynamics in subjects with bilateral vestibular loss (BVL) and healthy controls (C). Subjects stood with eyes closed on a rotating platform (±1.2° for frequencies ranging from 0.01–0.4 Hz in the presence and absence of light fingertip touch. Trunk movement relative to the platform of BVLs was higher than Cs at higher platform frequencies whereas leg movement relative to the platform was similar for both groups. With the addition of light touch, both groups showed similar trunk and leg segment movement relative to the platform. Trunk-leg coordination was in-phase for frequencies below 1 Hz and anti-phase above 1 Hz. Interestingly, BVLs showed evidence of a "legs-leading-trunk" relationship in the shift from in-phase to anti-phase around 1 Hz. Controls showed no preference for either segment to lead the coordinative shift from in- to anti-phase. The results suggest that the balance instability of BVL subjects stems from high variability of the trunk, rather than the legs. The high trunk variability may emerge from the "legs-leading" intersegmental relationship upon which BVLs rely. Because BVLs derive information about self-orientation primarily from the support surface when their eyes are closed, the legs initiate the shift to anti-phase trunk-leg coordination that is necessary for stable upright stance control. Higher trunk variability suggests that this strategy results in lower overall postural stability. Light touch substitutes for vestibular information, leading to lower trunk variability along with a trunk-leg phase shift similar to controls, without a preference for either segment to lead the shift. The results suggest that vestibulospinal control acts primarily to stabilize the trunk in space and to facilitate intersegmental dynamics.

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Effect of Tone on Directional Orientation during Stepping in Place with Eyes Closed

Perceptual and Motor Skills ◽

10.2466/pms.1995.80.3.719 ◽

1995 ◽

Vol 80 (3) ◽

pp. 719-722 ◽

Cited By ~ 1

Author(s):

Hideyuki Okuzumi ◽

Atsushi Tanaka ◽

Kouichi Haishi ◽

Tadayuki Sasaki

Keyword(s):

White Noise ◽

Pure Tone ◽

Angular Displacement ◽

Stationary Wave ◽

Eyes Closed ◽

Directional Orientation ◽

Tone Condition ◽

Interference Wave ◽

The Subject ◽

Stepping In Place

To examine the effect of a tone on directional orientation during stepping in place with eyes closed 10 healthy adults ages 20 to 27 years stepped in place for 120 seconds with eyes closed in 3 conditions: without a tone, with 1000-Hz pure tone, and with white noise. To examine how the subject rotated in stepping, both range and dispersion of the head's angular displacement were measured by a compass sensitive to terrestrial magnetism. Analysis showed that white noise was effective for directional orientation during stepping. Also, in the pure-tone condition, angular displacement of the head was similar to that in the no-tone condition. This result may have been due to the fact that the stationary wave created by the interference wave made sound normalization impossible.

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Influence of Leg Muscle Vibration on Human Walking

Journal of Neurophysiology ◽

10.1152/jn.2000.84.4.1737 ◽

2000 ◽

Vol 84 (4) ◽

pp. 1737-1747 ◽

Cited By ~ 85

Author(s):

Y. P. Ivanenko ◽

R. Grasso ◽

F. Lacquaniti

Keyword(s):

Stance Phase ◽

Walking Speed ◽

Triceps Surae ◽

Body Tilt ◽

Whole Body ◽

Muscle Vibration ◽

Eyes Closed ◽

Thigh Muscles ◽

Leg Muscle ◽

Stepping In Place

We studied the effect of vibratory stimulation of different leg muscles [bilateral quadriceps (Q), hamstring (HS) muscles, triceps surae (TS), and tibialis anterior (TA)] in seven normal subjects during 1) quiet standing, 2) stepping in place movements, and 3) walking on the treadmill. The experiments were performed in a dimly illuminated room, and the subjects were given the instruction not to resist the applied perturbation. In one condition the velocity of the treadmill was controlled by a feedback from the subject's current position. In normal standing, TA vibration elicited a prominent forward body tilt, whereas HS and TS vibration elicited backward trunk or whole body inclination, respectively. Q vibration had little effect. During stepping in place, continuous HS vibration produced an involuntary forward stepping at about 0.3 m s− 1 without modifying the stepping frequency. When the subjects (with eyes closed) kept a hand contact with an external still object, they did not move forward but perceived an illusory forward leg flexion relative to the trunk. Q, TS, and TA vibration did not cause any systematic body translation nor illusory changes in body configuration. In treadmill locomotion, HS vibration produced an involuntary steplike increase of walking speed (by 0.1–0.6 m·s− 1). Continuous vibration elicited larger speed increments than phasic stimulation during swing or stance phase. For phasic stimulation, HS vibration tended to be more effective when applied during swing than during stance phase. Q, TA, and TS vibration had little if any effect. Vibration of thigh muscles altered the walking speed depending on the direction of progression. During backward locomotion, the walking speed tended to decrease after HS vibration, whereas it significantly increased after Q vibration. Thus the influence of leg muscle vibration on stepping in place and locomotion differed significantly from that on normal posture. We suggest that the proprioceptive input from thigh muscles may convey information about the velocity of the foot movement relative to the trunk.

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Body balance in a free-standing position in road and off-road cyclists

Baltic Journal of Health and Physical Activity ◽

10.2478/bjha-2014-0022 ◽

2014 ◽

Vol 6 (4) ◽

Cited By ~ 1

Author(s):

Paulina Hebisz ◽

Rafal Hebisz ◽

Marek Zaton

Keyword(s):

Sagittal Plane ◽

Standing Position ◽

The Body ◽

Free Standing ◽

Body Balance ◽

Eyes Closed ◽

Road Cycling ◽

Progressive Exercise ◽

Before And After ◽

Road Cyclists

AbstractBackground: The purpose of this study was to compare body balance in road and off-road cyclists, immediately before and after the racing season.Material/Methods: Twenty individuals participated in the study and they were divided into two groups: specialists in road-cycling (n = 10) and in off-road cycling (n = 10). Immediately before and after the five-month racing season stabilographic trials were carried out (at rest and after progressive exercise). In assessing body balance the distance and velocity of the centre shifts (in the anterior-posterior and left-right direction) were analysed. The tests were performed with the cyclists’ eyes open, eyes closed, and in feedback.Results: After the racing season, in the off-road cyclists’ group, distance and velocity of the centre of pressure shifts increased after a progressive exercise.Conclusions: In the off-road cyclists’ group the balance of the body in the sagittal plane deteriorated after the racing season. Moreover, after the racing season off-road cyclists were characterized by a worse balance of the body, compared to road cyclists

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LABORATORY STUDIES OF THE OF EDDY FORMATION IN ROTATING AND NON-ROTATING FLUID DUE TO SPATIALLY NON-UNIFORM WIND FORCING

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.21610/conferencearticle_58b43175a0331 ◽

2017 ◽

Author(s):

Dmitry Elkin ◽

Andrey Zatsepin ◽

Andrey Zatsepin

Keyword(s):

Water Area ◽

The Black Sea ◽

Rotating Fluid ◽

Rotating Platform ◽

Cyclonic Vorticity ◽

Dipole Structure ◽

Air Jet ◽

Vortex Dipole ◽

Eddy Formation ◽

Observation Results

Laboratory investigation of eddy formation mechanism due to spatially non-uniform wind impact was fulfilled. Experiment was provided in a cylindrical and a square form tank filled with homogeneous or stratified fluid and displaced on a rotating platform. In the absence of the platform rotation, an impact of the single air jet lead to the formation of a symmetric vortex dipole structure that occupied the whole water area in the tank. In the presence of the platform rotation, a compact anticyclonic eddy was formed in a part of the dipole with anticyclonic vorticity, while in a part with cyclonic vorticity no any compact eddy was observed. The laboratory results were successfully compared with the field observation results fulfilled in the at the Black Sea coastal zone near Gelendzhik.

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A systematic review and meta-analysis on efficacy of exercise on posture and balance in patients suffering from Diabetic Neuropathy

Current Diabetes Reviews ◽

10.2174/1573399816666200703190437 ◽

2020 ◽

Vol 16 ◽

Author(s):

Neerja Thukral ◽

Jaspreet Kaur ◽

Manoj Malik

Keyword(s):

Diabetes Mellitus ◽

Diabetic Neuropathy ◽

Meta Analysis ◽

Berg Balance Scale ◽

Risk Of Bias ◽

Core Stability ◽

Balance Scale ◽

Eyes Closed ◽

Significant Difference ◽

Eyes Open

Background: Peripheral neuropathy is a major and chronic complication of diabetes mellitus affecting more than 50% of patients suffering from diabetes. There is involvement of both large and small diameter nerve fibres leading to altered somatosensory and motor sensations, thereby causing impaired balance and postural instability. Objective: To assess the effects of exercises on posture and balance in patients suffering from diabetes mellitus. Method: Mean changes in Timed Up and Go test(TUGT), Berg Balance Scale and Postural Sway with eyes open and eyes closed on Balance System were primary outcome measures. RevMan 5.3 software was used for the meta-analyses. Eighteen randomized controlled trials met the selection criteria and were included in the study. All the studies ranked high on PEDro Rating scale. Risk of bias was assessed by Cochrane collaboration tool of risk of bias. Included studies had low risk of bias. Sixteen RCT’s were included for the meta-analysis. Result: Results of meta-analysis showed that there was statistically significant improvement in TUGT with p≤ 0.05 and substantial heterogeneity (I 2 = 84%, p < 0.00001) in experimental group as compared to control group. There was statistically significant difference in Berg Balance Scale scores and heterogeneity of I 2 = 62%, p < 0.00001 and significant changes in postural stability (eyes open heterogeneity of I 2 = 100%, p =0.01 and eyes closed, heteogeneity I 2 = 0%, p =0.01). Sensitivity analysis causes change in heterogeneity. Conclusion: It can be concluded that various exercises like balance training, core stability, Tai-Chi, proprioceptive training etc. have a significant effect in improving balance and posture in diabetic neuropathy.

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Gender Differences in Postural Stability among 13-Year-Old Alpine Skiers

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17113859 ◽

2020 ◽

Vol 17 (11) ◽

pp. 3859 ◽

Cited By ~ 1

Author(s):

Agnieszka D. Jastrzębska

Keyword(s):

Gender Differences ◽

Postural Balance ◽

Lactate Concentration ◽

Blood Lactate Concentration ◽

Body Sway ◽

Foot Pressure ◽

Eyes Closed ◽

Before And After ◽

Eyes Open ◽

Alpine Skiers

This experiment examined changes in body sway after Wingate test (WAnT) in 19 adolescents practicing alpine skiing, subjected to the same type of training load for 4–5 years (10 girls and nine boys). The postural examinations were performed with eyes open (EO), eyes closed (EC), and sway reverenced vision (SRV) in the medial-lateral (ML) and anterior-posterior (AP) planes. The displacement of center of foot pressure (CoP), range of sway (RS), mean sway velocity (MV), way length, and surface area were measured in bipedal upright stance before and after the WAnT to assess the influence of fatigue on postural balance. There were no significant differences in WAnT parameters between girls and boys. Relative peak power (RPP), relative total work (RWtot) were (girls vs. boys) 8.89 ± 0.70 vs. 9.57 ± 1.22 W/kg, p < 0.05 and 227.91 ± 14.98 vs. 243.22 ± 30.24 W/kg, p < 0.05 respectively. The fatigue index (FI) was also on similar level in both genders; however, blood lactate concentration (BLa) was significantly higher in boys (10.35 ± 1.16 mM) than in girls (8.67 ± 1.35 mM) p = 0.007. In the EO examination, statistically significant differences between resting and fatigue conditions in the whole group and after the division into girls and boys were found. In fatigue conditions, significant gender differences were noted for measurements in the ML plane (sway path and RS) and RS in the AP plane. Comparison of the three conditions shows differences between EO vs. EC and SRV in AP plane measured parameters, and for RS in ML plane in rest condition in girls. The strong correlations between FI and CoP parameters mainly in ML plane in the whole group for all examination conditions were noted. By genders, mainly RS in ML plane strongly correlates with FI (r > 0.7). No correlation was found between BLa and CoP parameters (p > 0.06). The presented results indicate that subjecting adolescents of both genders to the same training may reduce gender differences in the postural balance ability at rest but not in fatigue conditions and that girls are significantly superior in postural balance in the ML plane than boys. It was also shown that too little or too much information may be destructive to postural balance in young adolescents.

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The effect of congenital blindness on resting-state functional connectivity revisited

Scientific Reports ◽

10.1038/s41598-021-91976-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Maria J. S. Guerreiro ◽

Madita Linke ◽

Sunitha Lingareddy ◽

Ramesh Kekunnaya ◽

Brigitte Röder

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Visual Experience ◽

Brain Regions ◽

State Condition ◽

Resting State Functional Connectivity ◽

Congenital Blindness ◽

Eyes Closed ◽

Congenitally Blind ◽

Eyes Open

AbstractLower resting-state functional connectivity (RSFC) between ‘visual’ and non-‘visual’ neural circuits has been reported as a hallmark of congenital blindness. In sighted individuals, RSFC between visual and non-visual brain regions has been shown to increase during rest with eyes closed relative to rest with eyes open. To determine the role of visual experience on the modulation of RSFC by resting state condition—as well as to evaluate the effect of resting state condition on group differences in RSFC—, we compared RSFC between visual and somatosensory/auditory regions in congenitally blind individuals (n = 9) and sighted participants (n = 9) during eyes open and eyes closed conditions. In the sighted group, we replicated the increase of RSFC between visual and non-visual areas during rest with eyes closed relative to rest with eyes open. This was not the case in the congenitally blind group, resulting in a lower RSFC between ‘visual’ and non-‘visual’ circuits relative to sighted controls only in the eyes closed condition. These results indicate that visual experience is necessary for the modulation of RSFC by resting state condition and highlight the importance of considering whether sighted controls should be tested with eyes open or closed in studies of functional brain reorganization as a consequence of blindness.

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Gait Stability Measurement by Using Average Entropy

Entropy ◽

10.3390/e23040412 ◽

2021 ◽

Vol 23 (4) ◽

pp. 412

Author(s):

Han-Ping Huang ◽

Chang Francis Hsu ◽

Yi-Chih Mao ◽

Long Hsu ◽

Sien Chi

Keyword(s):

Postural Stability ◽

Multiscale Entropy ◽

Gait Stability ◽

Eyes Closed ◽

Stride Interval ◽

Step Interval ◽

Stability Measurement ◽

Eyes Open ◽

Two Measures ◽

Better Than

Gait stability has been measured by using many entropy-based methods. However, the relation between the entropy values and gait stability is worth further investigation. A research reported that average entropy (AE), a measure of disorder, could measure the static standing postural stability better than multiscale entropy and entropy of entropy (EoE), two measures of complexity. This study tested the validity of AE in gait stability measurement from the viewpoint of the disorder. For comparison, another five disorders, the EoE, and two traditional metrics methods were, respectively, used to measure the degrees of disorder and complexity of 10 step interval (SPI) and 79 stride interval (SI) time series, individually. As a result, every one of the 10 participants exhibited a relatively high AE value of the SPI when walking with eyes closed and a relatively low AE value when walking with eyes open. Most of the AE values of the SI of the 53 diseased subjects were greater than those of the 26 healthy subjects. A maximal overall accuracy of AE in differentiating the healthy from the diseased was 91.1%. Similar features also exists on those 5 disorder measurements but do not exist on the EoE values. Nevertheless, the EoE versus AE plot of the SI also exhibits an inverted U relation, consistent with the hypothesis for physiologic signals.

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