Temporal dynamics of semicircular canal and otolith function following acute unilateral vestibular deafferentation in humans (original) (raw)
Related papers
Journal of Neurophysiology, 2006
Sadeghi SG, Minor LB, Cullen KE. Response of vestibular-nerve afferents to active and passive rotations under normal conditions and after unilateral labyrinthectomy. . We investigated the possible contribution of signals carried by vestibular-nerve afferents to long-term processes of vestibular compensation after unilateral labyrinthectomy. Semicircular canal afferents were recorded from the contralesional nerve in three macaque monkeys before [horizontal (HC) ϭ 67, anterior (AC) ϭ 66, posterior (PC) ϭ 50] and 1-12 mo after (HC ϭ 192, AC ϭ 86, PC ϭ 57) lesion. Vestibular responses were evaluated using passive sinusoidal rotations with frequencies of 0.5-15 Hz (20 -80°/s) and fast whole-body rotations reaching velocities of 500°/s. Sensitivities to nonvestibular inputs were tested by: 1) comparing responses during active and passive head movements, 2) rotating the body with the head held stationary to activate neck proprioceptors, and 3) encouraging head-restrained animals to attempt to make head movements that resulted in the production of neck torques of Յ2 Nm. Mean resting discharge rate before and after the lesion did not differ for the regular, D (dimorphic)-irregular, or C (calyx)-irregular afferents. In response to passive rotations, afferents showed no change in sensitivity and phase, inhibitory cutoff, and excitatory saturation after unilateral labyrinthectomy. Moreover, head sensitivities were similar during voluntary and passive head rotations and responses were not altered by neck proprioceptive or efference copy signals before or after the lesion. The only significant change was an increase in the proportion of C-irregular units postlesion, accompanied by a decrease in the proportion of regular afferents. Taken together, our findings show that changes in response properties of the vestibular afferent population are not likely to play a major role in the long-term changes associated with compensation after unilateral labyrinthectomy. Allum JH, Yamane M, Pfaltz CR. Long-term modifications of vertical and horizontal vestibulo-ocular reflex dynamics in man. I. After acute unilateral peripheral vestibular paralysis. Acta Otolaryngol 105: 328 -337, 1988. Andre-Deshays C, Revel M, Berthoz A. Eye-head coupling in humans. II. Phasic components. Exp Brain Res 84: 359 -366, 1991. Armand M, Minor LB. Relationship between time-and frequency-domain analyses of angular head movements in the squirrel monkey. J Comput Neurosci 11: 217-239, 2001. Baird RA, Desmadryl G, Fernandez C, Goldberg JM. The vestibular nerve of the chinchilla. II. Relation between afferent response properties and peripheral innervation patterns in the semicircular canals. J Neurophysiol 60: 182-203, 1988. Beraneck M, Idoux E, Uno A, Vidal PP, Moore LE, Vibert N. Unilateral labyrinthectomy modifies the membrane properties of contralesional vestibular neurons. J Neurophysiol 92: 1668 -1684, 2004. Bizzi E, Kalil RE, Tagliasco V. Eye-head coordination in monkeys: evidence for centrally patterned organization. Science 173: 452-454, 1971. Boyle R, Highstein SM. Efferent vestibular system in the toadfish: action upon horizontal semicircular canal afferents. J Neurosci 10: 1570 -1582, 1990. Bricout-Berthout A, Caston J, Reber A. Influence of stimulation of auditory and somatosensory systems on the activity of vestibular nuclear neurons in the frog. Brain Behav Evol 24: 21-34, 1984. Bronte-Stewart HM, Lisberger SG. Physiological properties of vestibular primary afferents that mediate motor learning and normal performance of the vestibulo-ocular reflex in monkeys. J Neurosci 14: 1290 -1308, 1994. Caston J, Bricout-Berthout A. Responses to somatosensory input by afferent and efferent neurons in the vestibular nerve of the frog. Brain Behav Evol 24: 135-143, 1984. Cullen KE, Minor LB. Semicircular canal afferents similarly encode active and passive head-on-body rotations: implications for the role of vestibular efference. J Neurosci 22: RC226, 2002. Cullen KE, Rey CG, Guitton D, Galiana HL. The use of system identification techniques in the analysis of oculomotor burst neuron spike train dynamics. J Comput Neurosci 3: 347-368, 1996. Curthoys IS, Halmagyi GM. Vestibular compensation: a review of the oculomotor, neural, and clinical consequences of unilateral vestibular loss.
Vestibular function in severe bilateral vestibulopathy
Journal of Neurology Neurosurgery and Psychiatry, 2001
Objectives-To assess residual vestibular function in patients with severe bilateral vestibulopathy comparing low frequency sinusoidal rotation with the novel technique of random, high acceleration rotation of the whole body. Methods-Eye movements were recorded by electro-oculography in darkness during passive, whole body sinusoidal yaw rotations at frequencies between 0.05 and 1.6 Hz in four patients who had absent caloric vestibular responses. These were compared with recordings using magnetic search coils during the first 100 ms after onset of whole body yaw rotation at peak accelerations of 2800°/s 2 . OV centre rotations added novel information about otolithic function. Results-Sinusoidal yaw rotations at 0.05 Hz, peak veocity 240°/s yielded minimal responses, with gain (eye velocity/head velocity)<0.02, but gain increased and phase decreased at frequencies between 0.2 and 1.6 Hz in a manner resembling the vestibulo-ocular reflex. By contrast, the patients had profoundly attenuated responses to both centred and eccentric high acceleration transients, representing virtually absent responses to this powerful vestibular stimulus. Conclusion-The analysis of the early ocular response to random, high acceleration rotation of the whole body disclosed a profound deficit of semicircular canal and otolith function in patients for whom higher frequency sinusoidal testing was only modestly abnormal. This suggests that the high frequency responses during sinusoidal rotation were of extravestibular origin. Contributions from the somatosensory or central predictor mechanisms, might account for the generation of these responses. Random, transient rotation is better suited than steady state rotation for quantifying vestibular function in vestibulopathic patients. (J Neurol Neurosurg Psychiatry 2001;71:53-57)
Ear, Nose & Throat Journal, 2019
The relationship between objective vestibular tests and subjective vestibular tests is a controversial topic. In this study, to contribute to this issue, the vestibulo-ocular reflex features and their relationship with balance perception at long-term follow-up in vestibular neurectomy (VN) and total labyrentectomy patients were evaluated. Prospectively, 19 VN and 18 labyrinthectomy patients were enrolled in this study. Patients underwent video head impulse test (VHIT) as objective vestibular test and dizziness handicap inventory (DHI) as subjective vestibular test when they attended to their control visit follow-up between March and September 2017. Lateral canal corrective saccades were classified as organized pattern and deorganized (scattered) pattern. In our results, the saccade pattern analysis (between organized and deorganized saccades) regarding the DHI scores gave P value as .039 for covert saccade pattern and .050 for overt saccade pattern. Therefore, we conclude that the p...
Journal of Neurophysiology
The role of the otoliths in mammals on the normal angular vestibulo-ocular reflex (VOR) was characterised in an accompanying study based on the Otopetrin1 (Otop1) mouse, which lacks functioning otoliths due to failure to develop otoconia but seems to have otherwise normal peripheral anatomy and neural circuitry. That study showed that otoliths do not contribute to the normal horizontal (rotation about Earth-vertical axis parallel to dorso-ventral axis) and vertical angular VOR (rotation about Earth-vertical axis parallel to inter-aural axis), but do affect gravity context-specific VOR adaptation. By using these animals, we sought to determine whether the otoliths play a role in the angular VOR after unilateral labyrinthectomy when the total canal signal is reduced. In 5 Otop1 and 5 control littermates we measured horizontal and vertical left-ear-down (LED) and (RED) sinusoidal VOR (0.2-10Hz, 20-100°/s) during the early (3-5 days) and plateau (28-32 days) phases of compensation follo...
2010
Ris, Laurence and Emile Godaux. Neuronal activity in the vestib-metries caused by a unilateral labyrinthectomy the driving force for restoration of activity? Here, we addressed these two questions ular nuclei after contralateral or bilateral labyrinthectomy in the alert guinea pig. J. Neurophysiol. 80: 2352Neurophysiol. 80: -2367Neurophysiol. 80: , 1998. In the by studying the spiking behavior of 473 second-order vestibular neurons in the alert guinea pig after a bilateral labyrinthectomy. guinea pig, a unilateral labyrinthectomy is followed by an initial depression and a subsequent restoration of the spontaneous activity In the acute stage, 1 h after bilateral labyrinthectomy, the resting discharge of the second-order vestibular neurons was 16.2 { 22.4 in the neurons of the ipsilateral vestibular nuclei. In two previous works, we have established the time course of these changes in spikes/s. From comparison with the results obtained in the acute stage after a unilateral labyrinthectomy, we inferred that the ipsilat-the alert guinea pig using electrical stimulation as a search stimulus to select the analyzed neurons. The latter criterion was important eral excitatory influence was between two and three times more powerful than the contralateral inhibitory influence. After bilateral to capture the many ipsilateral neurons that are silent at rest during the immediate postlabyrinthectomy stage. Because it is known that labyrinthectomy as well as after unilateral labyrinthectomy, the resting activity of the second-order vestibular neurons returned to a pathway originating from the vestibular nuclei on one side crosses the midline and functionally inhibits the activity of the vestibular normal, reaching 20.8 { 23.1 spikes/s 1 day after the lesion and 38.6 { 21.1 spikes/s 1 wk after the lesion. From this fact, we nuclei on the other side, we investigated in the first part of this study the spiking behavior of the neurons in the vestibular nuclei concluded that the left-right asymmetries caused by a unilateral labyrinthectomy were not the error signals inducing the restoration contralateral to the labyrinthectomy using the same procedure as that used for the ipsilateral neurons. The spiking behavior of 976 of activity. neurons was studied during 4-h recording sessions in intact animals and 1 h, 1 day, 2 days, or 1 wk postlabyrinthectomy. Neurons I N T R O D U C T I O N selected according to the electrical activation criterion were classified further as type I (their firing rate increased during ipsilateral 0022-3077/98 $5.00
Journal of Neurophysiology, 2009
Yakushin, Sergei B., Theodore Raphan, Jun-Ichi Suzuki, Yaresults in three push-pull pairs, right and left lateral (RLLL), suko Arai, and Bernard Cohen. Dynamics and kinematics of the right anterior and left posterior (RALP), and left anterior angular vestibulo-ocular reflex in monkey: effects of canal plugand right posterior (LARP), that code all angular head ging. J. Neurophysiol. 80: 3077-3099, 1998. Horizontal and roll movements. The precise angles of the individual semicircucomponents of the angular vestibulo-ocular reflex (aVOR) were lar canals have been estimated in several studies, which elicited by sinusoidal rotation at frequencies from 0.2 Hz (60Њ/s) indicate that the canal planes form a nonorthogonal basis to 4.0 Hz (É6Њ/s) in cynomolgus monkeys. Animals had both for sensing head acceleration (Blanks et al. 1985; Curthoys lateral canals plugged (VC, vertical canals intact), both lateral et al . 1977; Dickman 1996; Reisine et al. 1985. The canals and one pair of the vertical canals plugged (RALP, right 0022-3077/98 $5.00
NeuroRehabilitation, 2020
BACKGROUND: Only a few studies in the literature demonstrate the effect of vestibular rehabilitation (VR) on all vestibular receptor organs. Furthermore, very little evidence of the effect of VR on isolated otolith dysfunction (IOD) is available. OBJECTIVE: The study aimed to investigate the effect of VR on all vestibular receptor organs in patients with different types of unilateral vestibular hypofunction (UVH). METHODS: We enrolled 80 patients with three different types of UVH; combined and isolated loss of semicircular canal and otolith organ function. All patients performed a 12-week customized program of VR and received a full battery of vestibular function tests, before and after the VR. The DHI and SF-36 were performed before, after 6 weeks, and 12 weeks of the VR. RESULTS: Parameters of the caloric test, video head impulse test, ocular and cervical vestibular evoked myogenic potentials were significantly improved after VR. A total of 59 (74%) patients fully recovered, with ...
Ramachandran, Ramnarayan and Stephen G. Lisberger. Transformation of vestibular signals into motor commands in the vestibuloocular reflex pathways of monkeys. . Parallel pathways mediate the rotatory vestibuloocular reflex (VOR). If the VOR undergoes adaptive modification with spectacles that change the magnification of the visual scene, signals in one neural pathway are modified, whereas those in another are not. By recording the responses of vestibular afferents and abducens neurons for vestibular oscillations at frequencies from 0.5 to 50 Hz, we have elucidated how vestibular signals are processed in the modified versus unmodified VOR pathways. For the small stimuli we used (Ϯ15°/s), the afferents with the most regular spontaneous discharge fired throughout the cycle of oscillation even at 50 Hz, whereas afferents with more irregular discharge showed phase locking. For all afferents, the firing rate was in phase with stimulus head velocity at low frequencies and showed progressive phase lead as frequency increased. Sensitivity to head velocity increased steadily as a function of frequency. Abducens neurons showed highly regular spontaneous discharge and very little evidence of phase locking. Their sensitivity to head velocity during the VOR was relatively flat across frequencies; firing rate lagged head velocity at low frequencies and shifted to large phase leads as stimulus frequency increased. When afferent responses were provided as inputs to a two-pathway model of the VOR, the output of the model reproduced the responses of abducens neurons if the unmodified and modified VOR pathways had frequency-dependent internal gains and included fixed time delays of 1.5 and 9 ms. The phase shifts predicted by the model provide fingerprints for identifying brain stem neurons that participate in the modified versus unmodified VOR pathways.
2020
Unilateral vestibular hypofunction (UVH) patients were submitted to a vestibular rehabilitation (VR) program with two different protocols based on the unidirectional rotation paradigm. One group (N=28) was submitted to active gaze stabilization exercises with the head impulse test (HIT), and a second group (N=31) with the passive whole-body rotation on a rotatory chair. Head or body rotations were always performed to the hypofunction side and a similar number of training sessions were used in each group (2 times a week for four weeks). Patients in each group were subdivided into three subgroups based on the time delay between onset of the disease and beginning of VR (early VR: the first two weeks after onset; late 1 VR: third and fourth weeks after onset; late 2 VR: one month and more after onset). The angular vestibuloocular reflex (aVOR) and the directional preponderance (DP) regarding the horizontal canals were the main outcomes. The results pointed to similar findings with the t...