Use of galvanic vestibular feedback to control postural orientation in decerebrate rabbits

In quadrupeds, the dorsal-side-up body orientation during standing is maintained due to a postural system that is driven by feedback signals coming mainly from limb mechanoreceptors. In caudally decerebrated (postmammillary) rabbits, the efficacy of this system is considerably reduced. In this paper, we report that the efficacy of postural control in these animals can be restored with galvanic vestibular stimulation (GVS) applied transcutaneously to the labyrinths. In standing intact rabbits, GVS causes a lateral body sway towards the positive electrode. We used this GVS-caused sway to counteract the lateral body sway resulting from a mechanical perturbation of posture. Experiments were performed on postmammillary rabbits that stood on the tilting platform with their hindlimbs. To make the GVS value dependent on the postural perturbation (i.e., on the lateral body sway caused by tilt of the platform), an artificial feedback loop was formed in the following ways: 1) Information about the body sway was provided by a mechanical sensor; 2) The GVS current was applied when the sway exceeded a threshold value; the polarity of the current was determined by the sway direction. This simple algorithm allowed the “hybrid” postural system to maintain the dorsal-side-up orientation of the hindquarters when the platform was tilted by ± 20°. Thus, an important postural function, i.e., securing lateral stability during standing, can be restored in decerebrate rabbits with the GVS-based artificial feedback. We suggest that such a control system can compensate for the loss of lateral stability of various etiologies, and can be used for restoration of balance control in patients with impaired postural functions.

Download Full-text

Impairments of Postural Balance in Surgically Treated Lumbar Disc Herniation Patients

Journal of Applied Biomechanics ◽

10.1123/jab.2019-0341 ◽

2020 ◽

Vol 36 (4) ◽

pp. 228-234

Author(s):

Ziva M. Rosker ◽

Jernej Rosker ◽

Nejc Sarabon

Keyword(s):

Postural Balance ◽

Center Of Pressure ◽

Balance Control ◽

The Body ◽

Surface Velocity ◽

Body Sway ◽

Support Surface ◽

Balance Task ◽

Lateral Body ◽

Unstable Support

Reports on body sway control following microdiscectomy lack reports on side-specific balance deficits as well as the effects of trunk balance control deficits on body sway during upright stances. About 3 weeks post microdiscectomy, the body sway of 27 patients and 25 controls was measured while standing in an upright quiet stance with feet positioned parallel on an unstable support surface, a tandem stance with the involved leg positioned in front or at the back, a single-leg stance with both legs, and sitting on an unstable surface. Velocity, average amplitude, and frequency-direction–specific parameters were analyzed from the center of pressure movement, measured by the force plate. Statistically significant differences between the 2 groups were observed for the medial–lateral body sway frequency in parallel stance on a stable and unstable support surface and for the sitting balance task in medial-lateral body sway parameters. Medium to high correlations were observed between body sway during sitting and the parallel stance, as well as between the tandem and single-legged stances. Following microdiscectomy, deficits in postural balance were side specific, as expected by the nature of the pathology. In addition, the results of this study confirmed the connection between proximal balance control deficits and balance during upright quiet balance tasks.

Download Full-text

Pattern of Motor Coordination Underlying Backward Swimming in the Lamprey

Journal of Neurophysiology ◽

10.1152/jn.01277.2005 ◽

2006 ◽

Vol 96 (1) ◽

pp. 451-460 ◽

Cited By ~ 36

Author(s):

Salma S. Islam ◽

Pavel V. Zelenin ◽

Grigori N. Orlovsky ◽

Sten Grillner ◽

Tatiana G. Deliagina

Keyword(s):

Spinal Cord ◽

Motor Coordination ◽

Anterior Part ◽

Dorsal Side ◽

The Body ◽

Large Area ◽

Lower Vertebrate ◽

Complete Transection ◽

Lateral Body ◽

Propagating Waves

The main form of locomotion in the lamprey (a lower vertebrate, cyclostome) is forward swimming (FS) based on periodical waves of lateral body flexion propagating from head to tail. The lamprey is also capable of backward swimming (BS). Here we describe the kinematical and electromyographic (EMG) pattern of BS, as well as the effects on this pattern exerted by different lesions of the spinal cord. The BS was evoked by tactile stimulation of a large area in the anterior part of the body. Swimming was attributed to the waves of lateral body undulations propagating from tail to head. The EMG bursts on the two sides alternated, and the EMG in more caudal segments led in phase the EMG in more rostral segments. Main kinematical characteristics of BS strongly differed from those of FS: the amplitude of undulations was much larger and their frequency lower. Also, the maintenance of the dorsal-side-up body orientation ascribed to vestibular postural reflexes (typical for FS) was not observed during BS. A complete transection of the spinal cord did not abolish the generation of forward-propagating waves rostral to the lesion. After a lateral hemisection of the spinal cord, the BS pattern persisted on both sides rostral to the lesion; caudal to the lesion, it was present on the intact side and reduced or abolished on the lesioned side. The role of the spinal cord in generation of different forms of undulatory locomotion (FS and BS) is discussed.

Download Full-text

Head motion predictability explains activity-dependent suppression of vestibular balance control

10.1101/560664 ◽

2019 ◽

Author(s):

H Dietrich ◽

F Heidger ◽

R Schniepp ◽

PR MacNeilage ◽

S Glasauer ◽

...

Keyword(s):

Center Of Pressure ◽

Balance Control ◽

Vestibular Stimulation ◽

Head Movements ◽

Body Sway ◽

Cycle Phase ◽

Feed Forward ◽

Time Frequency ◽

Self Motion ◽

Activity Dependent

AbstractVestibular balance control is dynamically weighted during locomotion. This might result from a selective suppression of vestibular inputs in favor of a feed-forward balance regulation based on locomotor efference copies. The feasibility of such a feed-forward mechanism should however critically depend on the predictability of head movements (PHM) during locomotion. To test this, we studied in healthy subjects the differential impact of a stochastic vestibular stimulation (SVS) on body sway (center-of-pressure, COP) during standing and walking at different speeds using time-frequency analyses and compared it to activity-dependent changes in PHM. SVS-COP coupling decreased from standing to walking and further dropped with faster locomotion. Correspondingly, PHM increased with faster locomotion. Furthermore, SVS-COP coupling depended on the gait-cycle-phase with peaks corresponding to periods of least PHM. These findings support the assumption that during stereotyped human self-motion, locomotor efference copies selectively replace vestibular cues, similar to what was previously observed in animal models.

Download Full-text

The Effects of Stochastic Galvanic Vestibular Stimulation on Body Sway and Muscle Activity

Frontiers in Human Neuroscience ◽

10.3389/fnhum.2020.591671 ◽

2020 ◽

Vol 14 ◽

Author(s):

Akiyoshi Matsugi ◽

Kosuke Oku ◽

Nobuhiko Mori

Keyword(s):

Soleus Muscle ◽

Muscle Activity ◽

Center Of Pressure ◽

Vestibular Stimulation ◽

Galvanic Vestibular Stimulation ◽

The Body ◽

Lower Limbs ◽

Body Sway ◽

Eyes Open ◽

Significant Increment

Objective: This study aimed to investigate whether galvanic vestibular stimulation with stochastic noise (nGVS) modulates the body sway and muscle activity of the lower limbs, depending on visual and somatosensory information from the foot using rubber-foam.Methods: Seventeen healthy young adults participated in the study. Each subject maintained an upright standing position on a force plate with/without rubber-foam, with their eyes open/closed, to measure the position of their foot center of pressure. Thirty minutes after baseline measurements under four possible conditions (eyes open/closed with/without rubber-foam) performed without nGVS (intensity: 1 mA, duration: 40 s), the stimulation trials (sham-nGVS/real-nGVS) were conducted under the same conditions in random order, which were then repeated a week or more later. The total center of pressure (COP) path length movement (COP-TL) and COP movement velocity in the mediolateral (Vel-ML) and anteroposterior (Vel-AP) directions were recorded for 30 s during nGVS. Furthermore, electromyography activity of the right tibial anterior muscle and soleus muscle was recorded for the same time and analyzed.Results: Three-way analysis of variance and post-hoc multiple comparison revealed a significant increment in COP-related parameters by nGVS, and a significant increment in soleus muscle activity on rubber. There was no significant effect of eye condition on any parameter.Conclusions: During nGVS (1 mA), body sway and muscle activity in the lower limb may be increased depending not on the visual condition, but on the foot somatosensory condition.

Download Full-text

Dynamic Balance Measurement and Quantitative Assessment Using Wearable Plantar-Pressure Insoles in a Pose-Sensed Virtual Environment

Sensors ◽

10.3390/s18124193 ◽

2018 ◽

Vol 18 (12) ◽

pp. 4193 ◽

Cited By ~ 3

Author(s):

Cunguang Lou ◽

Chenyao Pang ◽

Congrui Jing ◽

Shuo Wang ◽

Xufeng He ◽

...

Keyword(s):

Plantar Pressure ◽

Evaluation System ◽

Balance Control ◽

Dynamic Balance ◽

Sports Injury ◽

The Body ◽

Assessment Process ◽

Body Sway ◽

Kinect Sensor ◽

Sit To Stand

The center of plantar pressure (COP) reflects the dynamic balance of subjects to a certain extent. In this study, wearable pressure insoles are designed, body pose measure is detected by the Kinect sensor, and a balance evaluation system is formulated. With the designed games for the interactive actions, the Kinect sensor reads the skeletal poses to judge whether the desired action is performed, and the pressure insoles simultaneously collect the plantar pressure data. The COP displacement and its speed are calculated to determine the body sway and the ability of balance control. Significant differences in the dispersion of the COP distribution of the 12 subjects have been obtained, indicating different balancing abilities of the examined subjects. A novel assessment process is also proposed in the paper, in which a correlation analysis is made between the de facto sit-to-stand (STS) test and the proposed method; the Pearson and Spearman correlations are also conducted, which reveal a significant positive correlation. Finally, four undergraduate volunteers with a right leg sports injury participate in the experiments. The experimental results show that the normal side and abnormal side have significantly different characters, suggesting that our method is effective and robust for balance measurements.

Download Full-text

Comparison of verticality perception and postural sway induced by double temple-mastoidal and bipolar binaural 20 Hz sinusoidal galvanic vestibular stimulation

Journal of Vestibular Research ◽

10.3233/ves-210112 ◽

2021 ◽

pp. 1-15

Author(s):

Samar Babaee ◽

Moslem Shaabani ◽

Mohsen Vahedi

Keyword(s):

Postural Sway ◽

Maximum Amplitude ◽

Semicircular Canals ◽

Vestibular Stimulation ◽

Galvanic Vestibular Stimulation ◽

The Body ◽

Body Sway ◽

Mean Values ◽

Amplitude Change ◽

Threshold Levels

BACKGROUND: Galvanic vestibular stimulation (GVS) is believed to be one of the most valuable tools for studying the vestibular system. In our opinion, its combined effect on posture and perception needs to be examined more. OBJECTIVE: The present study was conducted to investigate the effect of a 20 Hz sinusoidal Galvanic Vestibular Stimulation (sGVS) on the body sway and subjective visual vertical (SVV) deviation through two sets of electrode montages (bipolar binaural and double temple-mastoidal stimulation) during a three-stage experiment (baseline, threshold, and supra-threshold levels). METHODS: While the individuals (32 normal individuals, 10 males, the mean age of 25.37±3.00 years) were standing on a posturography device and SVV goggles were put on, the parameters of the body sway and SVV deviation were measured simultaneously. Following the baseline stage (measuring without stimulation), the parameters were investigated during the threshold and supra-threshold stages (1 mA above the threshold) for 20 seconds. This was done separately for each electrode montage. Then, the results were compared between the three experimental stages and the two electrode montages. RESULTS: In both electrode montages, “the maximum amplitude” of the mediolateral (ML) and anteroposterior (AP) body sway decreased and increased in the threshold and supra-threshold stages, respectively, compared to the baseline stage. Comparison of the amount of “amplitude change” caused by each electrode montages showed that the double temple-mastoidal stimulation induced a significantly greater amplitude change in body sway during both threshold and supra-threshold stages (relative to the baseline stage). The absolute mean values of the SVV deviation were significantly different between the baseline and supra-threshold levels in both electrode montages. The SVV deviation in double temple-mastoidal stimulation was a bit greater than that in the bipolar binaural stimulation. CONCLUSION: Double temple-mastoidal stimulation has induced greater amount of change in the body sway and SVV deviation. This may be due to the more effective stimulation of the otoliths than semicircular canals.

Download Full-text

Spatial orientation in the lamprey. II. Visual influence on orientation during locomotion and in the attached state

Journal of Experimental Biology ◽

10.1242/jeb.198.3.675 ◽

1995 ◽

Vol 198 (3) ◽

pp. 675-681

Author(s):

F Ullén ◽

T G Deliagina ◽

G N Orlovsky ◽

S Grillner

Keyword(s):

Visual Stimulation ◽

Video Recording ◽

Light Response ◽

Longitudinal Axis ◽

Vestibular Stimulation ◽

Dorsal Side ◽

Transverse Plane ◽

The Body ◽

Negative Phototaxis ◽

Contralateral Eye

The responses of attached lampreys to homogeneous visual stimulation and the role of visual stimuli in orientation during locomotion were investigated. Experiments were performed by video recording the responses of intact and lesioned animals to illumination. The following results were obtained. 1. In lampreys attached with their sucker mouth to the bottom of the aquarium, illumination of one eye evoked several possible motor responses (ordered after mean latency): (a) movement of the illuminated eye downwards, and the contralateral eye upwards; (b) rotation of the body around the longitudinal axis, with the illuminated side tilting downwards; (c) deviation of the caudal part of the anterior dorsal fin in the contralateral direction (away from the light); and (d) flexion of the neck and body towards the side of illumination. 2. Illumination of one eye in attached lampreys often resulted in detachment and subsequent movement in a direction away from the light source (negative phototaxis). This response was not related to the degree of roll tilt before detachment, so the negative phototaxis does not appear to be a consequence of the vestibular stimulation. 3. Negative phototaxis was also seen during locomotion: lampreys turned through 180 ° when they approached a brightly illuminated area. Photostimulation also affected their orientation in the transverse plane during swimming. Illumination of one eye from the side induced a roll movement, so that the illuminated side tilted downwards and the dorsum of the lamprey became turned towards the light. This is similar to the 'dorsal light response' of fish and shows that vision also plays a role in postural control in lampreys. 4. The behaviour of blinded animals differed strikingly from that of intact ones. Whereas intact animals preferentially swam close to the bottom, along horizontal trajectories, blinded animals showed episodes of continuous swimming upwards, near the water surface. During horizontal swimming, their orientation in the transverse plane remained normal, with the dorsal side up.

Download Full-text

Influence of Stance Width on Frontal Plane Postural Dynamics and Coordination in Human Balance Control

Journal of Neurophysiology ◽

10.1152/jn.00916.2009 ◽

2010 ◽

Vol 104 (2) ◽

pp. 1103-1118 ◽

Cited By ~ 59

Author(s):

Adam D. Goodworth ◽

Robert J. Peterka

Keyword(s):

Frequency Response ◽

Balance Control ◽

Frontal Plane ◽

Body Motion ◽

Upper Body ◽

Body Sway ◽

Support Surface ◽

Lower Body ◽

Stimulus Amplitude ◽

Postural System

The influence of stance width on frontal plane postural dynamics and coordination in human bipedal stance was studied. We tested the hypothesis that when subjects adopt a narrow stance width, they will rely heavily on nonlinear control strategies and coordinated counter-phase upper and lower body motion to limit center-of-mass (CoM) deviations from upright; as stance increases, the use of these strategies will diminish. Freestanding frontal plane body sway was evoked through continuous pseudorandom rotations of the support surface on which subjects stood with various stimulus amplitudes. Subjects were either eyes open (EO) or closed (EC) and adopted various stance widths. Upper body, lower body, and CoM kinematics were summarized using root-mean-square and peak-to-peak measures, and dynamic behavior was characterized using frequency-response and impulse-response functions. In narrow stance, CoM frequency-response function gains were reduced with increasing stimulus amplitude and in EO compared with EC; in wide stance, gain reductions were much less pronounced. Results show that the narrow stance postural system is nonlinear across stimulus amplitude in both EO and EC conditions, whereas the wide stance postural system is more linear. The nonlinearity in narrow stance is likely caused by an amplitude-dependent sensory reweighting mechanism. Finally, lower body and upper body sway were approximately in-phase at low frequencies (<1 Hz) and out-of-phase at high frequencies (>1 Hz) across all stance widths, and results were therefore inconsistent with the hypothesis that subjects made greater use of coordinated counter-phase upper and lower body motion in narrow compared with wide stance conditions.

Download Full-text

Postural Responses Evoked by Platform Pertubations Are Dominated by Continuous Feedback

Journal of Neurophysiology ◽

10.1152/jn.00457.2006 ◽

2007 ◽

Vol 98 (2) ◽

pp. 730-743 ◽

Cited By ~ 62

Author(s):

Herman van der Kooij ◽

Erwin de Vlugt

Keyword(s):

Balance Control ◽

The Body ◽

Body Sway ◽

Intermittent Control ◽

Feedback Mechanisms ◽

Ankle Torque ◽

Eyes Closed ◽

Postural Responses ◽

Continuous Feedback ◽

Time Invariant

Is human balance control dominated by time invariant continuous feedback mechanisms or do noncontinuous mechanisms play a significant role like intermittent control? The goal of this paper is to quantify how much of the postural responses evoked by pseudorandom external periodic perturbations can be explained by continuous time invariant feedback control. Nine healthy subjects participated in this study. Center of mass and ankle torque responses were elicited by periodic platform perturbations in forward-backward directions containing energy in the 0.06- to 4.5-Hz frequency band. Subjects had their eyes open (EO) or eyes closed (EC). Responses were decomposed into a periodic component and a remnant (stochastic) component using spectral analysis. It is concluded that periodic responses can explain most of the evoked responses, although the remnant power spectral densities (PSDs) were significant especially for slow responses (<0.2 Hz) and largest for EC. The found remnant PSD did depend on the sensory condition but not on the platform perturbation amplitude. The ratio of the body sway and ankle torque remnant PSD reflects the body dynamics. Both findings are consistent with the idea that estimation of body orientation is part of a continuous feedback loop and that (stochastic) estimation errors increase when one source of sensory information is removed. The findings are not consistent with the idea that discrete or discontinuous intermittent feedback mechanisms significantly shape postural responses.

Download Full-text

Effects of galvanic vestibular stimulation on postural limb reflexes and neurons of spinal postural network

Journal of Neurophysiology ◽

10.1152/jn.00041.2012 ◽

2012 ◽

Vol 108 (1) ◽

pp. 300-313 ◽

Cited By ~ 10

Author(s):

L.-J. Hsu ◽

P. V. Zelenin ◽

G. N. Orlovsky ◽

T. G. Deliagina

Keyword(s):

Vestibular Stimulation ◽

Afferent Input ◽

Galvanic Vestibular Stimulation ◽

Dorsal Side ◽

Body Orientation ◽

Cathode Side ◽

Body Sway ◽

Postural Control System ◽

Opposite Pattern ◽

Neuronal Mechanisms

Quadrupeds maintain the dorsal side up body orientation due to the activity of the postural control system driven by limb mechanoreceptors. Binaural galvanic vestibular stimulation (GVS) causes a lateral body sway toward the anode. Previously, we have shown that this new position is actively stabilized, suggesting that GVS changes a set point in the reflex mechanisms controlling body posture. The aim of the present study was to reveal the underlying neuronal mechanisms. Experiments were performed on decerebrate rabbits. The vertebral column was rigidly fixed, whereas hindlimbs were positioned on a platform. Periodic lateral tilts of the platform caused postural limb reflexes (PLRs): activation of extensors in the loaded and flexing limb and a decrease in extensor activity in the opposite (unloaded and extending) limb. Putative spinal interneurons were recorded in segments L4–L5 during PLRs, with and without GVS. We have found that GVS enhanced PLRs on the cathode side and reduced them on the anode side. This asymmetry in PLRs can account for changes in the stabilized body orientation observed in normal rabbits subjected to continuous GVS. Responses to platform tilts (frequency modulation) were observed in 106 spinal neurons, suggesting that they can contribute to PLR generation. Two neuron groups were active in opposite phases of the tilt cycle of the ipsi-limb: F-neurons in the flexion phase, and E-neurons in the extension phase. Neurons were driven mainly by afferent input from the ipsi-limb. If one supposes that F- and E-neurons contribute, respectively, to excitation and inhibition of extensor motoneurons, one can expect that the pattern of response to GVS in F-neurons will be similar to that in extensor muscles, whereas E-neurons will have an opposite pattern. We have found that ∼40% of all modulated neurons meet this condition, suggesting that they contribute to the generation of PLRs and to the GVS-caused changes in PLRs.

Download Full-text