Effect of gaze on postural responses to neck proprioceptive and vestibular stimulation in humans (original) (raw)
Related papers
Neuroscience Letters, 1999
We have previously shown that postural responses to vibration of neck dorsal muscles (NS) and to galvanic stimulation of the vestibular system (GS) are in¯uenced by the direction of gaze. Here, we describe the time course of this effect. We found that eye orienting movements during NS induce shifts of body inclination toward the direction of gaze with a latency of about 2 s: the time course is smooth and a steady state is attained after about 5 s from eye movements. If eye eccentricity is maintained and NS or GS are sequentially repeated for as long as 2 min, the direction of sway drifts in the direction opposite to eye deviation. The ®ndings reveal that the frames of reference for the control of posture may have a dynamic nature. q
Effects of neck muscles vibration on the perception of the head and trunk midline position
Experimental Brain Research, 2006
The present study focused on the inXuence of neck vibration on the perception of the head and trunk midline position (orientation and localization). The orientation of the head and trunk was investigated by the rolling adjustment of a rod on their midline while their localization was investigated by the adjustment of the position of a visual dot as being straight-ahead the eyes or the sternum. The Wrst experiment investigated whether a head-trunk dissociation was induced by the unilateral vibration of neck muscles in upright and restrained subjects. Results showed that the subjective orientation and localization of whole-body midline were shifted toward the vibrated side. The second experiment determined the eVect of the neck muscles vibration when the subjects were lying on their side. The eVect of vibration disappeared when the side of vibration was opposed to the side of postural inclination and it was stronger than in the upright position when the side of vibration and the side of postural inclination were congruent. Whereas, results suggested that the input from neck muscle proprioceptors participates directly to the elaboration of the egocentric space, the question may be raised as to how the sensory cues interacted in their contribution to the neural generation of an egocentric, body centred coordinate system.
Local and global effects of neck muscle vibration during stabilization of upright standing
Experimental Brain …, 2011
Neck muscle vibration (NMV) during upright standing is known to induce forward leaning, which has been explained as a global response to the (illusory) perception of a lengthening of the dorsal neck muscles. However, the effects of NMV both at the level of individual joints and on whole-body postural coordination, and its potential modulation by vision, have not yet been analyzed in detail. Eight healthy young adult participants completed a total of ten trials each, with a 10-s period of unperturbed standing followed by a 10-s period of NMV. Participants were instructed to stand ''as still as possible''. This postural task was executed under two visual conditions: eyes open (EO) and eyes closed (EC). Postural responses were measured in terms of center of pressure (CoP) and center of mass (CoM) profiles, and whole-body kinematics. Responses to NMV at the level of individual body segments and joints were assessed by decomposing the time series into linear trends and residual fluctuations. Inter-segmental coordination was analyzed using a decorrelation technique, assessing motor-equivalent stabilization of four task-related variables: CoM position, trunk orientation, as well as head position and orientation. NMV induced a general forward leaning response under both visual conditions, visible in CoP, CoM, segment positions and orientations. Locally, NMV induced a pronounced extension of the atlanto-occipital joint. Residual fluctuations were higher with EC and unaffected by NMV. Coordination analysis showed that stabilization of different body parts was differentially affected by NMV. Head orientation was consistently stabilized across all conditions, with weaker coordination in the EC condition. In contrast, motor-equivalent stabilization of CoM and head position, and trunk orientation was only observed during no-vibration periods. Taken together, our results demonstrate specific effects of vision and proprioception on different aspects of local and global postural control. While perturbed neck proprioception seemed to affect the postural ''set point'' (inducing forward leaning), vision appeared to mainly serve in noise reduction (residual fluctuations) and control of head orientation.
Neck proprioception shapes body orientation and perception of motion
Frontiers in human neuroscience, 2014
This review article deals with some effects of neck muscle proprioception on human balance, gait trajectory, subjective straight-ahead (SSA), and self-motion perception. These effects are easily observed during neck muscle vibration, a strong stimulus for the spindle primary afferent fibers. We first remind the early findings on human balance, gait trajectory, SSA, induced by limb, and neck muscle vibration. Then, more recent findings on self-motion perception of vestibular origin are described. The use of a vestibular asymmetric yaw-rotation stimulus for emphasizing the proprioceptive modulation of motion perception from the neck is mentioned. In addition, an attempt has been made to conjointly discuss the effects of unilateral neck proprioception on motion perception, SSA, and walking trajectory. Neck vibration also induces persistent aftereffects on the SSA and on self-motion perception of vestibular origin. These perceptive effects depend on intensity, duration, side of the cond...
Neurophysiologie Clinique, 2019
Background.-Neck muscle vibration (NMV) is increasingly used for its modulation of body orientation and spatial perception, but its mechanisms of action are still not well known. Objectives.-To describe the effects of NMV on postural orientation and spatial perception, in both healthy people and patients with disturbed balance potentially related to distorted body orientation perception. Methods.-Following the PRISMA guidelines, a systematic search was performed using the databases MEDLINE, EMBASE, Cochrane library and PEDrO with the key words ((Postural balance) OR (Spatial reference)) AND (Neck muscle vibration) for articles published through to July 2016. Results.-A total of 67 articles were assessed; these exhibited wide heterogeneity and generally poor quality methodology. In healthy subjects, under bilateral NMV, the body tilts in the anterior direction (Level of Evidence LoE II). Under unilateral NMV, the visual environment moves towards the side opposite the vibration (LoE II) and the subject's experience of ''straight ahead'' is shifted towards the side of the vibration (LoE II). NMV also modulates both spatial and postural bias between stroke and vestibular patients.
Neck Muscle Vibration and Spatial Orientation During Stepping in Place in Humans
Journal of Neurophysiology, 2002
Unilateral long-lasting vibration was applied to the sternomastoid muscle to assess the influence of asymmetric neck proprioceptive input on body orientation during stepping-in-place. Blindfolded subjects performed 3 sequences of 3 trials, each lasting 60 s: control, vibration applied during stepping (VDS), and vibration applied before stepping (VBS). VDS caused clear-cut whole body rotation toward the side opposite to vibration. The body rotated around a vertical axis placed at about arm's length from the body. The rotation did not begin immediately on switching on the vibrator. The delay varied from subject to subject from a few seconds to about 10 s. Once initiated, the angular velocity of rotation was remarkably constant (about 1°/s). In VBS, at the beginning of stepping, subjects rotated for a while as if their neck were still vibrated. At a variable delay, the direction of rotation reversed, and the effects were opposite to those observed during VDS. Under no condition did...
Asymmetric whole-body back-and-forth yaw rotation induces a bias in vestibular self-motion perception. The perceptive bias is modulated by unilateral neck muscle vibration, depending on the function of the vibrated neck muscle. The bias in the modulation can persist several hours depending on frequency and duration of the vibration train. a b s t r a c t Objective: To show that neck proprioceptive input can induce long-term effects on vestibular-dependent self-motion perception. Methods: Motion perception was assessed by measuring the subject's error in tracking in the dark the remembered position of a fixed target during whole-body yaw asymmetric rotation of a supporting platform , consisting in a fast rightward half-cycle and a slow leftward half-cycle returning the subject to the initial position. Neck muscles were relaxed or voluntarily contracted, and/or vibrated. Whole-body rotation was administered during or at various intervals after the vibration train. The tracking position error (TPE) at the end of the platform rotation was measured during and after the muscle conditioning maneuvers. Results: Neck input produced immediate and sustained changes in the vestibular perceptual response to whole-body rotation. Vibration of the left sterno-cleido-mastoideus (SCM) or right splenius capitis (SC) or isometric neck muscle effort to rotate the head to the right enhanced the TPE by decreasing the perception of the slow rotation. The reverse effect was observed by activating the contralateral muscle. The effects persisted after the end of SCM conditioning, and slowly vanished within several hours, as tested by late asymmetric rotations. The aftereffect increased in amplitude and persistence by extending the duration of the vibration train (from 1 to 10 min), augmenting the vibration frequency (from 5 to 100 Hz) or contracting the vibrated muscle. Symmetric yaw rotation elicited a negligible TPE, upon which neck muscle vibrations were ineffective. Conclusions: Neck proprioceptive input induces enduring changes in vestibular-dependent self-motion perception, conditional on the vestibular stimulus feature, and on the side and the characteristics of vibration and status of vibrated muscles. This shows that our perception of whole-body yaw-rotation is not only dependent on accurate vestibular information, but is modulated by proprioceptive information related to previously experienced position of head with respect to trunk. Please cite this article in press as: Pettorossi VE et al. Long-lasting effects of neck muscle vibration and contraction on self-motion perception of vestibular origin. Clin Neurophysiol (2015), http://dx.doi.org/10.1016/j.clinph.2015.02.057 Significance: Tonic proprioceptive inflow, as might occur as a consequence of enduring or permanent head postures, can induce adaptive plastic changes in vestibular-dependent motion sensitiveness. These changes might be counteracted by vibration of selected neck muscles.
Eye movements evoked by proprioceptive stimulation along the body axis in humans
Experimental Brain Research, 1998
Proprioceptive input arising from torsional body movements elicits small reflexive eye movements. The functional relevance of these eye movements is still unknown so far. We evaluated their slow components as a function of stimulus frequency and velocity. The horizontal eye movements of seven adult subjects were recorded using an infrared device, while horizontal rotations were applied at three segmental levels of the body [i.e., between head and shoulders (neck stimulus), shoulders and pelvis (trunk stimulus), and pelvis and feet (leg stimulus)]. The following results were obtained: (1) Sinusoidal leg stimulation evoked an eye response with the slow component in the direction of the movement of the feet, while the response to trunk and neck stimulation was oriented in the opposite direction (i.e., in that of the head). (2) In contrast, the gain behavior of all three responses was similar, with very low gain at mid-to high frequencies (tested up to 0.4 Hz) but increasing gain at low frequencies (down to 0.0125 Hz). We show that this gain behavior is mainly due to a gain nonlinearity for low angular velocities. The responses were compatible with linear summation when an interaction series was tested in which the leg stimulus was combined with a vestibular stimulus. (4) There was good correspondence of the median gain curves when eye responses were compared with psychophysical responses (perceived body rotation in space; additionally recorded in the interaction series). However, correlation of gain values on a single-trial basis was poor. (5) During transient neck stimulation (smoothed position ramp), the neck response noticeably consisted of two components ± an initial head-directed eye shift (phasic component) followed by a shift in the opposite direction (compensatory tonic component). Both leg and neck responses can be described by one simple, dynamic model. In the model the proprioceptive input is fed into the gaze network via two pathways which differ in their dynamics and directional sign. The model simu-lates either leg or neck responses by selecting an appropriate weight for the gain of one of the pathways (phasic component). The interaction results can also be simulated when a vestibular path is added. This model has similarities to one we recently proposed for human self-motion perception and postural control. A major difference, though, is that the proprioceptive input to the gaze-stabilizing network is weak (restricted to low velocities), unlike that used for perception and postural control. We hold that the former undergoes involution during ontogenesis, as subjects depend on the functionally more appropriate vestibulo-ocular reflex. Yet, the weak proprioceptive eye responses that remain may have some functional relevance. Their tonic component tends to stabilize the eyes by slowly shifting them toward the primary head position relative to the body support. This applies solely to the earth-horizontal plane in which the vestibular signal has no static sensitivity.
Effect of vision, proprioception, and the position of the vestibular organ on postural sway
Acta Oto-laryngologica, 2010
Conclusion: When measured together, it seems that vision and proprioception as well as position of the vestibular organ affect postural sway, vision the most. Mediolateral (ML) sway does not seem to be influenced by the position of the vestibular organ. Objective: To investigate how postural sway was affected by provocation of vision, by the position of the vestibular organ, and by provocation of proprioception, when measured together. Methods: Postural sway was measured by using a force plate. Tests were performed with eyes open and eyes closed, with head in neutral position and rotated to the right and to the left and with head maximally extended, both standing on firm surface and on foam. Measures of ML speed (mm/s), anteriorposterior (AP) speed (mm/s), and sway area (SA) (mm 2 /s) were analyzed using a multilevel approach. Results: The multilevel analysis revealed how postural sway was significantly affected by closed eyes and standing on foam, and by the position of the vestibular organ. Closed eyes and standing on foam both significantly prolonged the dependent measurement, irrespective of whether it was ML, AP or SA. However, only AP and SA were significantly affected by vestibular position, i.e. maximal head movement to the right and extension of the head.
Disturbed cervical proprioception affects perception of spatial orientation while in motion
Experimental Brain Research, 2017
muscles and to a non-vibration baseline condition. During the tests a forward displacement ("Moved distance") was found to be the normal behavior, with various degrees of longitudinal rotation ("Rotation"). The moved distance was significantly larger when the vibration was applied on the dorsal muscles (916 mm) relative to on ventral muscles (715 mm) (p = 0.003) and the rate of displacement was significantly larger for dorsal muscles (36.5 mm/s) relative to ventral (28.7 mm/s) vs (p = 0.002). When vibration was applied on the left-sided muscles, 16° rotation to the right was induced (p = 0.005), whereas no significant rotation direction was induced with right-sided vibration (3°). The rate of rotation was significantly larger for vibration applied on ventral muscles (0.44°/s) relative to on dorsal (0.33°/s) (p = 0.019). The results highlight the influence of cervical proprioception on the internal spatial orientation, and subsequent for postural control.