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.

scholarly journals Pulsed Infrared Stimulation of Vertical Semicircular Canals Evokes Cardiovascular Changes in the Rat

2021 ◽  
Vol 12 ◽  
Author(s):  
Darrian Rice ◽  
Giorgio P. Martinelli ◽  
Weitao Jiang ◽  
Gay R. Holstein ◽  
Suhrud M. Rajguru
Keyword(s):  
Heart Rate ◽  
Nervous System ◽  
Semicircular Canal ◽  
Parasympathetic Nervous System ◽  
Semicircular Canals ◽  
Whole Body ◽  
Experimental Session ◽  
Otolith Organs ◽  
Vertical Semicircular Canals ◽  
Stimulation Of

A variety of stimuli activating vestibular end organs, including sinusoidal galvanic vestibular stimulation, whole body rotation and tilt, and head flexion have been shown to evoke significant changes in blood pressure (BP) and heart rate (HR). While a role for the vertical semicircular canals in altering autonomic activity has been hypothesized, studies to-date attribute the evoked BP and HR responses to the otolith organs. The present study determined whether unilateral activation of the posterior (PC) or anterior (AC) semicircular canal is sufficient to elicit changes in BP and/or HR. The study employed frequency-modulated pulsed infrared radiation (IR: 1,863 nm) directed via optical fibers to PC or AC of adult male Long-Evans rats. BP and HR changes were detected using a small-animal single pressure telemetry device implanted in the femoral artery. Eye movements evoked during IR of the vestibular endorgans were used to confirm the stimulation site. We found that sinusoidal IR delivered to either PC or AC elicited a rapid decrease in BP and HR followed by a stimulation frequency-matched modulation. The magnitude of the initial decrements in HR and BP did not correlate with the energy of the suprathreshold stimulus. This response pattern was consistent across multiple trials within an experimental session, replicable, and in most animals showed no evidence of habituation or an additive effect. Frequency modulated electrical current delivered to the PC and IR stimulation of the AC, caused decrements in HR and BP that resembled those evoked by IR of the PC. Frequency domain heart rate variability assessment revealed that, in most subjects, IR stimulation increased the low frequency (LF) component and decreased the high frequency (HF) component, resulting in an increase in the LF/HF ratio. This ratio estimates the relative contributions of sympathetic nervous system (SNS) and parasympathetic nervous system (PNS) activities. An injection of atropine, a muscarinic cholinergic receptor antagonist, diminished the IR evoked changes in HR, while the non-selective beta blocker propranolol eliminated changes in both HR and BP. This study provides direct evidence that activation of a single vertical semicircular canal is sufficient to activate and modulate central pathways that control HR and BP.

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.

Semicircular canal and saccular influence on the subjective visual horizontal during gondola centrifugation

1999 ◽  
Vol 9 (5) ◽  
pp. 347-357
Author(s):  
A. Tribukait
Keyword(s):  
Semicircular Canal ◽  
Semicircular Canals ◽  
Central Position ◽  
Otolith Organs ◽  
Force Vector ◽  
Time Constants ◽  
Storage Mechanism ◽  
Spatial Disorientation ◽  
Gravitoinertial Force ◽  
Vertical Semicircular Canals

Measurements of the subjective visual horizontal (SVH) were performed in 11 healthy test persons during an increase of the resultant gravitoinertial force vector in a large swing-out gondola centrifuge. Three levels of hypergravity (1.5g, 2.0g, 2.5g) were used, each with a duration of 4 minutes and with 1–2 minute pauses at 1.0g in between. The direction of the resultant gravitoinertial force vector was always parallel with the head and body length axis. Hence, there was no roll stimulus to the otolith organs. The swing-out of the gondola during acceleration, however, is sensed by the vertical semicircular canals as a change in roll head position, thus creating an otolith-semicircular canal conflict. After acceleration of the centrifuge there was a tilt of the SVH relative to the resultant gravitoinertial horizontal. This tilt gradually decayed during the 4-minute period of recordings. For a subgroup of seven test subjects who had completely normal ENG-recordings in 1g environment, the initial offset of SVH and the time constants for exponential decay were determined for each g level; initial offsets: 9 . 9 ∘ (1.5g), 7 . 7 ∘ (2.0g), 6 . 1 ∘ (2.5g); time constants: 89s (1.5g), 74s (2.0g), 37s (2.5g). The offset of SVH is interpreted as being the result of mainly the stimulus to the vertical semicircular canals during acceleration of the centrifuge. The slow decay, however, does not correspond to the dynamics of the semicircular canal system, and is suggested to reflect some kind of central position storage mechanism. A smaller offset and more rapid decay for the higher g loads may be explained by an increasing dominance of graviceptive input, presumably from the saccules. In conclusion, these results might suggest the role of the vertical semicircular canals as well as the sacculus in the formation of SVH. They may also have relevance with regard to the spatial disorientation problem in aviators.

Sympathetic nerve activity during natural stimulation of horizontal semicircular canals in humans

1998 ◽  
Vol 275 (4) ◽  
pp. R1274-R1278 ◽  
Author(s):  
Chester A. Ray ◽  
Keith M. Hume ◽  
Samuel L. Steele
Keyword(s):  
Sympathetic Nerve ◽  
Sympathetic Nerve Activity ◽  
Semicircular Canals ◽  
Head Rotation ◽  
Otolith Organs ◽  
Nerve Activity ◽  
Natural Stimulation ◽  
Vascular Beds ◽  
Static Head ◽  
Stimulation Of

We have shown that static head-down neck flexion elicits increases in muscle (MSNA) but not skin sympathetic nerve activity (SSNA) in humans. These findings suggest that stimulation of the otolith organs causes differential sympathetic outflow to vascular beds. The purpose of the present study was to determine whether yaw head rotation (YHR), which stimulates the horizontal semicircular canals, elicits sympathetic nerve responses. To test this question, we recorded MSNA ( n = 33) and SSNA ( n = 25) before and during 3 min of sinusoidal YHR performed at 0.1, 0.6, and 1.0 Hz. At all frequencies, YHR elicited no significant changes in heart rate and mean arterial pressure. Likewise, YHR did not significantly change either MSNA or SSNA at all frequencies. Our results indicate that stimulation of the horizontal semicircular canals by YHR does not alter SNA to either muscle or skin. Moreover, these results provide evidence to support the concept that the otolith organs but not the horizontal semicircular canals participate in the regulation of SNA in humans.

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.

Experimentally Induced Motion Sickness in Fish: Possible Role of the Otolith Organs

2003 ◽  
Vol 123 (4) ◽  
pp. 488-492 ◽  
Author(s):  
Kai Helling ◽  
Stefan Hausmann ◽  
Andrew Clarke ◽  
Hans Scherer
Keyword(s):  
Motion Sickness ◽  
Otolith Organs ◽  
Induced Motion ◽  
Experimentally Induced

Reforming the System of Non-Material Stimulation of Personnel of the Enterprises of Socio-Cultural Sphere

2016 ◽  
Vol 5 (4) ◽  
pp. 23-29
Author(s):  
Еникеева ◽  
L. Enikeeva ◽  
Кузьмина ◽  
S. Kuzmina
Keyword(s):  
Necessary Condition ◽  
Efficient Operation ◽  
Corporate System ◽  
Effective Delivery ◽  
Basic Functions ◽  
Cultural Sphere ◽  
Stimulation System ◽  
Material Stimulation ◽  
Stimulation Of

In the article the urgency of reforming the system of material incentives for the personnel in the socio-cultural sphere is defined. The main theoretical and practical aspects of application of various forms of non-material stimulation of the personnel at the example of reform of system of stimulation of work of the staff of the cinema „Aurora“ are considered. The authors reveals the essence of the system of stimulation of work of staff, the role of non-material stimulation of labor, discusses the relationship between such concepts as „needs“, „stimulus“, „motive“. The basic functions performed by incentive: economic, social and moral functions. The essence of the concept „motivation“ is not only the establishment of such a mechanism, in which active and producing some results-employment, becomes a necessary condition for satisfaction of important needs of employees, but also to use corporate-system, social and socio-psychological forms of non-material incentives of personnel of the enterprise, the need for which justified the analysis of the results of the survey of employees of socio-cultural sphere. In this article the formation of a system of motivation and non-material incentives for employees of enterprises of film screening that will ensure effective delivery of services to consumers the movies-video is considered. It was found that the stimulation system is satisfactory, but there is a possibility of reducing the efficiency of the system due to the indifference of employees towards their work, lack of initiative. So workers don‘t want to be involved in resolution of the problems in the team. The personnel‘s interest in efficient operation is clarified, but the existing shortcomings in the system of nonmaterial stimulation, in the opinion of the working team, in varying degrees, affect job satisfaction and reduce it.

Sign in / Sign up

Export Citation Format

Share Document