scholarly journals Contribution of intravestibular sensory conflict to motion sickness and dizziness in migraine disorders

2016 ◽  
Vol 116 (4) ◽  
pp. 1586-1591 ◽  
Author(s):  
Joanne Wang ◽  
Richard F. Lewis
Keyword(s):  
Motion Sickness ◽  
Semicircular Canals ◽  
Inverse Correlation ◽  
Normal Subjects ◽  
Otolith Organs ◽  
Rotational Axis ◽  
Vestibuloocular Reflex ◽  
Sensory Conflict ◽  
Velocity Signal ◽  
Episodic Vertigo

Migraine is associated with enhanced motion sickness susceptibility and can cause episodic vertigo [vestibular migraine (VM)], but the mechanisms relating migraine to these vestibular symptoms remain uncertain. We tested the hypothesis that the central integration of rotational cues (from the semicircular canals) and gravitational cues (from the otolith organs) is abnormal in migraine patients. A postrotational tilt paradigm generated a conflict between canal cues (which indicate the head is rotating) and otolith cues (which indicate the head is tilted and stationary), and eye movements were measured to quantify two behaviors that are thought to minimize this conflict: suppression and reorientation of the central angular velocity signal, evidenced by attenuation (“dumping”) of the vestibuloocular reflex and shifting of the rotational axis of the vestibuloocular reflex toward the earth vertical. We found that normal and migraine subjects, but not VM patients, displayed an inverse correlation between the extent of dumping and the size of the axis shift such that the net “conflict resolution” mediated through these two mechanisms approached an optimal value and that the residual sensory conflict in VM patients (but not migraine or normal subjects) correlated with motion sickness susceptibility. Our findings suggest that the brain normally controls the dynamic and spatial characteristics of central vestibular signals to minimize intravestibular sensory conflict and that this process is disrupted in VM, which may be responsible for the enhance motion intolerance and episodic vertigo that characterize this disorder.

Eyes on Target: What Neurons Must do for the Vestibuloocular Reflex During Linear Motion

2004 ◽  
Vol 92 (1) ◽  
pp. 20-35 ◽  
Author(s):  
Dora E. Angelaki
Keyword(s):  
Sensory Information ◽  
Semicircular Canals ◽  
Linear Acceleration ◽  
Head Rotation ◽  
Oculomotor System ◽  
Eye Position ◽  
Otolith Organs ◽  
Vestibuloocular Reflex ◽  
Linear Motion ◽  
Gaze Stabilization

A gaze-stabilization reflex that has been conserved throughout evolution is the rotational vestibuloocular reflex (RVOR), which keeps images stable on the entire retina during head rotation. An ethological newer reflex, the translational or linear VOR (TVOR), provides fast foveal image stabilization during linear motion. Whereas the sensorimotor processing has been extensively studied in the RVOR, much less is currently known about the neural organization of the TVOR. Here we summarize the computational problems faced by the system and the potential solutions that might be used by brain stem and cerebellar neurons participating in the VORs. First and foremost, recent experimental and theoretical evidence has shown that, contrary to popular beliefs, the sensory signals driving the TVOR arise from both the otolith organs and the semicircular canals. Additional unresolved issues include a scaling by both eye position and vergence angle as well as the temporal transformation of linear acceleration signals into eye-position commands. Behavioral differences between the RVOR and TVOR, as well as distinct differences in neuroanatomical and neurophysiological properties, raise multiple functional questions and computational issues, only some of which are readily understood. In this review, we provide a summary of what is known about the functional properties and neural substrates for this oculomotor system and outline some specific hypotheses about how sensory information is centrally processed to create motor commands for the VORs.

THE ROLE OF THE SEMICIRCULAR CANALS IN CAUSATION OF MOTION SICKNESS AND NYSTAGMUS IN THE DOG

1964 ◽  
Vol 42 (6) ◽  
pp. 793-801 ◽  
Author(s):  
K. E. Money ◽  
J. Friedberg
Keyword(s):  
Motion Sickness ◽  
Surgical Procedures ◽  
Semicircular Canals ◽  
Otolith Organs ◽  
Basic Functions ◽  
Functional Inactivation ◽  
Vertical Semicircular Canals ◽  
Stimulation Of

The discrete surgical inactivation of all six semicircular canals was found to be equivalent to bilateral labyrinthectomy in eliminating motion sickness in dogs, even though the otolith organs remained functional. Inactivation of fewer than six of the canals reduced the susceptibility of dogs to motion sickness, but to a lesser degree than did inactivation of all six canals. These findings are consistent with the theory that stimulation of the semicircular canals causes motion sickness.Rotatory tests of the horizontal and vertical semicircular canals and tests of an otolith reflex, preoperatively and postoperatively, yielded information about the basic functions of the semicircular canals and confirmed that the surgical procedures had accomplished their objectives without unintended damage to other vestibular receptors.

Effect of viewing distance and location of the axis of head rotation on the monkey's vestibuloocular reflex. I. Eye movement responses

1992 ◽  
Vol 67 (4) ◽  
pp. 861-874 ◽  
Author(s):  
L. H. Snyder ◽  
W. M. King
Keyword(s):  
Eye Movement ◽  
Visual Target ◽  
Head Rotation ◽  
Rotational Axis ◽  
Viewing Distance ◽  
Vestibuloocular Reflex ◽  
Velocity Signal ◽  
Head Velocity ◽  
Axis Of Rotation ◽  
Pure Delay

1. The vestibuloocular reflex (VOR) stabilizes images on the retina against movements of the head in space. Viewing distance, target eccentricity, and location of the axis of rotation may influence VOR responses because rotation of the head about most axes in space rotates and translates the eyes relative to visual targets. To study the VOR response to combined rotation and translation, monkeys were placed on a rate table and rotated briefly in the dark about a vertical axis that was located in front of or behind the eyes. The monkeys fixated a near or far visual target that was extinguished before the rotation. Eye movements were recorded from both eyes by the use of the search coil technique. 2. Peak eye velocity evoked by the VOR was linearly related to vergence angle for any axis of rotation. The percent change in the VOR with near target viewing relative to far target viewing at a vergence angle of 20 degrees was linearly related to the location of the axis of rotation. Axes located behind the eyes produced positive changes in VOR amplitude, and axes located in front of the eyes produced negative changes in VOR amplitude. An axis of rotation located in the coronal plane containing the centers of rotation of the eyes produced no modification of VOR amplitude. For any axis, the VOR compensated for approximately 90% of the translation of the eye relative to near targets. 3. The initial VOR response was not correct in magnitude but was refined by a series of three temporally delayed corrections of increasing complexity. The earliest VOR-evoked eye movement (10-20 ms after rotation onset) was independent of viewing distance and rotational axis location. In the next 100 ms, eye speed appeared to be sequentially modified three times: within 20 ms by viewing distance; within 30 ms by otolith translation; and within 100 ms by eye translation relative to the visual target. 4. These data suggest a formal model of the VOR consisting of four channels. Channel 1 conveys an unmodified head rotation signal with a pure delay of 10 ms. Channel 2 conveys an angular head velocity signal, modified by viewing distance with a pure delay of 20 ms, but invariant with respect to the location of the axis of rotation. Channel 3 conveys a linear head velocity signal, dependent on the location of the axis of rotation, that is modified by viewing distance with a pure delay of 30 ms.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals The neural basis of motion sickness

2019 ◽  
Vol 121 (3) ◽  
pp. 973-982 ◽  
Author(s):  
Bernard Cohen ◽  
Mingjia Dai ◽  
Sergei B. Yakushin ◽  
Catherine Cho
Keyword(s):  
Motion Sickness ◽  
Semicircular Canals ◽  
Signs And Symptoms ◽  
Vestibular Nuclei ◽  
The Body ◽  
Velocity Storage ◽  
Otolith Organs ◽  
Neural Basis ◽  
Sense Orientation ◽  
Roll Tilt

Although motion of the head and body has been suspected or known as the provocative cause for the production of motion sickness for centuries, it is only within the last 20 yr that the source of the signal generating motion sickness and its neural basis has been firmly established. Here, we briefly review the source of the conflicts that cause the body to generate the autonomic signs and symptoms that constitute motion sickness and provide a summary of the experimental data that have led to an understanding of how motion sickness is generated and can be controlled. Activity and structures that produce motion sickness include vestibular input through the semicircular canals, the otolith organs, and the velocity storage integrator in the vestibular nuclei. Velocity storage is produced through activity of vestibular-only (VO) neurons under control of neural structures in the nodulus of the vestibulo-cerebellum. Separate groups of nodular neurons sense orientation to gravity, roll/tilt, and translation, which provide strong inhibitory control of the VO neurons. Additionally, there are acetylcholinergic projections from the nodulus to the stomach, which along with other serotonergic inputs from the vestibular nuclei, could induce nausea and vomiting. Major inhibition is produced by the GABAB receptors, which modulate and suppress activity in the velocity storage integrator. Ingestion of the GABAB agonist baclofen causes suppression of motion sickness. Hopefully, a better understanding of the source of sensory conflict will lead to better ways to avoid and treat the autonomic signs and symptoms that constitute the syndrome.

Horizontal Vestibuloocular Reflex Evoked by High-Acceleration Rotations in the Squirrel Monkey. II. Responses After Canal Plugging

1999 ◽  
Vol 82 (3) ◽  
pp. 1271-1285 ◽  
Author(s):  
David M. Lasker ◽  
Douglas D. Backous ◽  
Anna Lysakowski ◽  
Griffin L. Davis ◽  
Lloyd B. Minor
Keyword(s):  
High Frequency ◽  
Peak Velocity ◽  
Vestibular Function ◽  
Semicircular Canals ◽  
Vestibuloocular Reflex ◽  
Half Cycle ◽  
High Acceleration ◽  
Linear And Nonlinear ◽  
Residual Response ◽  
Sinusoidal Rotations

The horizontal angular vestibuloocular reflex (VOR) evoked by high-frequency, high-acceleration rotations was studied in four squirrel monkeys after unilateral plugging of the three semicircular canals. During the period (1–4 days) that animals were kept in darkness after plugging, the gain during steps of acceleration (3,000°/s2, peak velocity = 150°/s) was 0.61 ± 0.14 (mean ± SD) for contralesional rotations and 0.33 ± 0.03 for ipsilesional rotations. Within 18–24 h after animals were returned to light, the VOR gain for contralesional rotations increased to 0.88 ± 0.05, whereas there was only a slight increase in the gain for ipsilesional rotations to 0.37 ± 0.07. A symmetrical increase in the gain measured at the plateau of head velocity was noted after animals were returned to light. The latency of the VOR was 8.2 ± 0.4 ms for ipsilesional and 7.1 ± 0.3 ms for contralesional rotations. The VOR evoked by sinusoidal rotations of 0.5–15 Hz, ±20°/s had no significant half-cycle asymmetries. The recovery of gain for these responses after plugging was greater at lower than at higher frequencies. Responses to rotations at higher velocities for frequencies ≥4 Hz showed an increase in contralesional half-cycle gain, whereas ipsilesional half-cycle gain was unchanged. A residual response that appeared to be canal and not otolith mediated was noted after plugging of all six semicircular canals. This response increased with frequency to reach a gain of 0.23 ± 0.03 at 15 Hz, resembling that predicted based on a reduction of the dominant time constant of the canal to 32 ms after plugging. A model incorporating linear and nonlinear pathways was used to simulate the data. The coefficients of this model were determined from data in animals with intact vestibular function. Selective increases in the gain for the linear and nonlinear pathways predicted the changes in recovery observed after canal plugging. An increase in gain of the linear pathway accounted for the recovery in VOR gain for both responses at the velocity plateau of the steps of acceleration and for the sinusoidal rotations at lower peak velocities. The increase in gain for contralesional responses to steps of acceleration and sinusoidal rotations at higher frequencies and velocities was due to an increase in the gain of the nonlinear pathway. This pathway was driven into inhibitory cutoff at low velocities and therefore made no contribution for rotations toward the ipsilesional side.

Responses of interneurons in the cat cervical cord to vestibular tilt stimulation

1986 ◽  
Vol 56 (4) ◽  
pp. 1147-1156 ◽  
Author(s):  
R. H. Schor ◽  
I. Suzuki ◽  
S. J. Timerick ◽  
V. J. Wilson
Keyword(s):  
Cervical Spinal Cord ◽  
Semicircular Canals ◽  
Body Tilt ◽  
Whole Body ◽  
Cervical Cord ◽  
Otolith Organs ◽  
Phase Lag ◽  
Response Dynamics ◽  
Decerebrate Cat ◽  
Propriospinal Neurons

The responses of interneurons in the cervical spinal cord of the decerebrate cat to whole-body tilt were studied with a goal of identifying spinal elements in the production of forelimb vestibular postural reflexes. Interneurons both in the cervical enlargement and at higher levels, from which propriospinal neurons have been identified, were examined, both in animals with intact labyrinths and in animals with nonfunctional semicircular canals (canal plugged). Most cervical interneurons responding to tilt respond best to rotations in vertical planes aligned within 30 degrees of the roll plane. Two to three times as many neurons are excited by side-up roll tilt as are excited by side-down roll. In cats with intact labyrinths, most responses have dynamics proportional either to (and in phase with) the position of the animal or to a sum of position and tilt velocity. This is consistent with input from both otolith organs and semicircular canals. In animals without functioning canals, the "velocity" response is absent. In a few cells (8 out of 76), a more complex response, characterized by an increasing gain and progressive phase lag, was observed. These response dynamics characterize the forelimb reflex in canal-plugged cats and have been previously observed in vestibular neurons in such preparations.

Probing the human vestibular system with galvanic stimulation

2004 ◽  
Vol 96 (6) ◽  
pp. 2301-2316 ◽  
Author(s):  
Richard C. Fitzpatrick ◽  
Brian L. Day
Keyword(s):  
Balance Control ◽  
Semicircular Canals ◽  
Vestibular Nuclei ◽  
Vestibular Stimulation ◽  
Otolith Organs ◽  
Sources Of Information ◽  
Electrophysiological Studies ◽  
Human Balance ◽  
Cortical Inputs ◽  
Vestibular Organs

Galvanic vestibular stimulation (GVS) is a simple, safe, and specific way to elicit vestibular reflexes. Yet, despite a long history, it has only recently found popularity as a research tool and is rarely used clinically. The obstacle to advancing and exploiting GVS is that we cannot interpret the evoked responses with certainty because we do not understand how the stimulus acts as an input to the system. This paper examines the electrophysiology and anatomy of the vestibular organs and the effects of GVS on human balance control and develops a model that explains the observed balance responses. These responses are large and highly organized over all body segments and adapt to postural and balance requirements. To achieve this, neurons in the vestibular nuclei receive convergent signals from all vestibular receptors and somatosensory and cortical inputs. GVS sway responses are affected by other sources of information about balance but can appear as the sum of otolithic and semicircular canal responses. Electrophysiological studies showing similar activation of primary afferents from the otolith organs and canals and their convergence in the vestibular nuclei support this. On the basis of the morphology of the cristae and the alignment of the semicircular canals in the skull, rotational vectors calculated for every mode of GVS agree with the observed sway. However, vector summation of signals from all utricular afferents does not explain the observed sway. Thus we propose the hypothesis that the otolithic component of the balance response originates from only the pars medialis of the utricular macula.

scholarly journals Convergence of linear acceleration and yaw rotation signals on non-eye movement neurons in the vestibular nucleus of macaques

2018 ◽  
Vol 119 (1) ◽  
pp. 73-83 ◽  
Author(s):  
Shawn D. Newlands ◽  
Ben Abbatematteo ◽  
Min Wei ◽  
Laurel H. Carney ◽  
Hongge Luan
Keyword(s):  
Eye Movement ◽  
Multisensory Integration ◽  
Vestibular Nucleus ◽  
Semicircular Canals ◽  
Linear Acceleration ◽  
Vestibular Nuclei ◽  
Otolith Organs ◽  
Angular Rotation ◽  
Sensory Signals ◽  
Nonlinear Integration

Roughly half of all vestibular nucleus neurons without eye movement sensitivity respond to both angular rotation and linear acceleration. Linear acceleration signals arise from otolith organs, and rotation signals arise from semicircular canals. In the vestibular nerve, these signals are carried by different afferents. Vestibular nucleus neurons represent the first point of convergence for these distinct sensory signals. This study systematically evaluated how rotational and translational signals interact in single neurons in the vestibular nuclei: multisensory integration at the first opportunity for convergence between these two independent vestibular sensory signals. Single-unit recordings were made from the vestibular nuclei of awake macaques during yaw rotation, translation in the horizontal plane, and combinations of rotation and translation at different frequencies. The overall response magnitude of the combined translation and rotation was generally less than the sum of the magnitudes in responses to the stimuli applied independently. However, we found that under conditions in which the peaks of the rotational and translational responses were coincident these signals were approximately additive. With presentation of rotation and translation at different frequencies, rotation was attenuated more than translation, regardless of which was at a higher frequency. These data suggest a nonlinear interaction between these two sensory modalities in the vestibular nuclei, in which coincident peak responses are proportionally stronger than other, off-peak interactions. These results are similar to those reported for other forms of multisensory integration, such as audio-visual integration in the superior colliculus. NEW & NOTEWORTHY This is the first study to systematically explore the interaction of rotational and translational signals in the vestibular nuclei through independent manipulation. The results of this study demonstrate nonlinear integration leading to maximum response amplitude when the timing and direction of peak rotational and translational responses are coincident.

Influence of Otolith Organs, Semicircular Canals, and Neck Afferents on Post-Rotatory Nystagmus

1996 ◽  
Vol 6 (5) ◽  
pp. 319-329 ◽  
Author(s):  
Izumi Koizuka ◽  
Robert H. Schor ◽  
Joseph M. Furman
Keyword(s):  
Semicircular Canals ◽  
Otolith Organs ◽  
Neck Afferents
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