Postural Responses Evoked by Sinusoidal Galvanic Stimulation of the Labyrinth: Influence of Head Position

Hlavačka, F; Njiokiktjien, C

doi:10.3109/00016488509119152

Cited by 65 publications

(22 citation statements)

References 9 publications

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“…This is consistent with earlier reports that sway direction varies with head rotation (Nashner & Wolfson, 1974;Lund & Broberg, 1983;Hlavacka & Njiokiktjien, 1985;Tokita, Ito & Takagi, 1989). Integration of vestibular and head position signals is essential in species where the head can be turned relative to the supporting limbs.…”

Section: Effects Of Vestibular Stimulation On Motoneuronessupporting

confidence: 81%

Vestibular‐evoked postural reactions in man and modulation of transmission in spinal reflex pathways.

Iles¹,

Pisini²

1992

The Journal of Physiology

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SUMMARY1. The effects of galvanic stimulation of the vestibular apparatus (with electrodes on the mastoid processes) have been studied in standing human subjects. With the head turned to one side, subjects swayed towards the anode.2. Forwards sway was preceded by electromyographic (EMG) activity in quadriceps and tibialis anterior muscles. Backwards sway was preceded by EMG activity in soleus and hamstring muscles.3. Using the method of H reflex conditioning, forward sway was found to be preceded by inhibition of soleus motoneurones.4. Interaction between the vestibular-evoked inhibition of soleus motoneurones preceding forwards sway and peripheral reflex inhibition was examined by a spatial facilitation method.5. Interaction was found between vestibular-evoked inhibition and la reciprocal, group I non-reciprocal and group Ia-Ia presynaptic inhibitory pathways. It is concluded that vestibular signals converge on spinal interneurones subserving these inhibitory actions. 6. A 'decoupling' of soleus motoneurones and soleus-coupled Renshaw cells was found in the period of soleus activation preceding backwards sway.

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Section: Effects Of Vestibular Stimulation On Motoneuronessupporting

confidence: 81%

Vestibular‐evoked postural reactions in man and modulation of transmission in spinal reflex pathways.

Iles¹,

Pisini²

1992

The Journal of Physiology

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“…In an analogous way, an abnormal, asymmetric input from the neck would induce deviation of the "straight-ahead" toward the side opposite to the augmented input. Since neck afferents have a modulatory influence on the direction of vestibulo-spinal motor effects in human (Hlavacka and Nijokiktjien 1985) and play a role in shaping the output of the primate vestibular nucleus and its contribution to posture, gaze, and perception (Gdowski and McCrea 2000), the vibration-elicited neck input could modulate the activity of the vestibular nuclei and mimic a rotation of head on shoulder, thereby driving the body to rotate. The neck proprioceptive messages would also contribute, together with visual information of eye position, in determining gaze direction (Han and Lennerstrand 1995).…”

Section: Discussionmentioning

confidence: 99%

Neck Muscle Vibration and Spatial Orientation During Stepping in Place in Humans

Bove

Courtine

Schieppati

2002

Journal of Neurophysiology

117

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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 head rotation, head roll, or lateral body tilt accompany rotation. The results confirm and extend the notion that the neck proprioceptive input plays a major role in body orientation during locomotion. The body rotation does not seem to depend on the same mechanisms that modify the erect posture; rather, the asymmetric neck input would seem to modify the egocentric body-centered coordinate system.

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“…Third, although a fully compensatory shift of the RVO for any imposed trunk displacement seems desirable for the effector muscles of the vestibulospinal reflex arc, there is, to our knowledge, no definite evidence to prove that they do indeed behave in this ideal way. The abovementioned studies that examined the influence of trunk displacement on vestibularly evoked body sway or EMG responses in leg muscles (Fransson et al 2000;Hlavacka and Njiokiktjien 1985;Kennedy and Inglis 2002;Tokita et al 1989Tokita et al , 1991, are, in this respect, qualitative in nature. A fully compensatory RVO shift was described for trunk displacements of Ϯ30°in the triceps muscle in decerebrate cats (Manzoni et al 1998).…”

Section: Responses To Trunk Displacementmentioning

confidence: 99%

“…For instance, using transmastoidal galvanic vestibular stimulation, Hlavacka and Njiokiktjien (1985) and Fransson et al (2000) showed that the plane of the induced reflectory body sway rotated systematically to remain approximately aligned with the interaural line, when the head was turned from the straight-ahead position to the side. Similarly, systematic changes in vestibularly evoked electromyographic responses in leg muscles were demonstrated after changes in head-on-trunk position (Kennedy and Inglis 2002;Tokita et al 1989Tokita et al , 1991.…”

Section: Introductionmentioning

confidence: 99%

Trunk Position Influences Vestibular Responses of Fastigial Nucleus Neurons in the Alert Monkey

Kleine

Guan

Kipiani

et al. 2004

Journal of Neurophysiology

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. Vestibulospinal reflexes play an important role for body stabilization during locomotion and for postural control. For an appropriate distribution of vestibular signals to spinal motoneurons, the orientation of the body relative to the head needs to be taken into account. For different trunk positions, identical vestibular stimuli must activate different sets of muscles to ensure body stabilization. Because the cerebellar vermis and the underlying fastigial nucleus (FN) might be involved in this task, vestibular neurons in the rostral FN of alert rhesus monkeys were recorded during sinusoidal vestibular stimulation (0.1-1.0 Hz) in the roll and pitch planes at different trunk-re-head positions (center and Ϯ45°). From the sensitivity and phase values measured in these planes, the response properties in the intermediate planes and the stimulus orientation eliciting the optimal response [response vector orientation (RVO)] were calculated. In most neurons, the RVOs rotated systematically with respect to the head, when trunk-re-head position was altered, so that they tended to maintain their orientation with respect to the trunk. Sensitivity and phase at the RVO were not affected. This pattern was the same for neurons in the right and left FN and independent of stimulus frequency. The average sensitivity of this partially compensatory RVO shift in response to trunk-re-head displacements, evaluated by linear regression analyses, was 0.59°/°(n ϭ 73 neurons). These data show that FN neurons may encode vestibular information in a coordinate system that is closer to a trunk-centered than to a head-centered reference frame. They indicate an important role of this nucleus in motor programs related to posture and gait control.

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Postural Responses Evoked by Sinusoidal Galvanic Stimulation of the Labyrinth: Influence of Head Position

Cited by 65 publications

References 9 publications

Vestibular‐evoked postural reactions in man and modulation of transmission in spinal reflex pathways.

Vestibular‐evoked postural reactions in man and modulation of transmission in spinal reflex pathways.

Neck Muscle Vibration and Spatial Orientation During Stepping in Place in Humans

Trunk Position Influences Vestibular Responses of Fastigial Nucleus Neurons in the Alert Monkey

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