Motion Sickness Produced by Head Movement as a Function of Rotational Velocity

Motion Sickness Produced by Head Movement as a Function of Rotational Velocity PDF

Author: Earl F. Miller (II)

Publisher:

Published: 1970

Total Pages: 20

ISBN-13:

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To measure the stressor stimulus effect of rotational velocity in terms of the number of the standardized head tilt movements required to evoke a common severity level of symptoms characterizing motion sickness, sixteen young healthy subjects were rotated in a laboratory (Stille) rotational chair at various velocities within a range suitable for each subject and the limits of 1.0 to 30.0 rpm. Standardized 90 degree head movements were executed at each test velocity until the preselected and quantitatively determined motion sickness endpoint of moderate (M IIA) or severe (M III) malaise was reached. When individual ability to make head movements without evoking symptoms was exceeded, the derived average stressor effect (E factor) of each head movement varied directly and, in log-log terms, linearly with rotational velocity. These data provide the basis for grading individual susceptibility to Coriolis (motion) sickness with a single numerical score as well as define the high rate of change of Coriolis stressor effect as a function of rotational velocity, which may find practical application for specifying rotational rates of space stations. (Author).

Motion Sickness Produced by Head Movement as a Function of Rotational Velocity

Motion Sickness Produced by Head Movement as a Function of Rotational Velocity PDF

Author: Earl F Miller (II.)

Publisher:

Published: 1970

Total Pages: 15

ISBN-13:

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To measure the stressor stimulus effect of rotational velocity in terms of the number of the standardized head tilt movements required to evoke a common severity level of symptoms characterizing motion sickness, sixteen young healthy subjects were rotated in a laboratory (Stille) rotational chair at various velocities within a range suitable for each subject and the limits of 1.0 to 30.0 rpm. Standardized 90 degree head movements were executed at each test velocity until the preselected and quantitatively determined motion sickness endpoint of moderate (M IIA) or severe (M III) malaise was reached. When individual ability to make head movements without evoking symptoms was exceeded, the derived average stressor effect (E factor) of each head movement varied directly and, in log-log terms, linearly with rotational velocity. These data provide the basis for grading individual susceptibility to Coriolis (motion) sickness with a single numerical score as well as define the high rate of change of Coriolis stressor effect as a function of rotational velocity, which may find practical application for specifying rotational rates of space stations. (Author).

Motion Sickness Produced by Head Movement as a Function of Rotational Velocity

Motion Sickness Produced by Head Movement as a Function of Rotational Velocity PDF

Author:

Publisher:

Published: 1970

Total Pages: 0

ISBN-13:

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To measure the stressor stimulus effect of rotational velocity in terms of the number of the standardized head tilt movements required to evoke a common severity level of symptoms characterizing motion sickness, sixteen young healthy subjects were rotated in a laboratory (Stille) rotational chair at various velocities within a range suitable for each subject and the limits of 1.0 to 30.0 rpm. Standardized 90 degree head movements were executed at each test velocity until the preselected and quantitatively determined motion sickness endpoint of moderate (M IIA) or severe (M III) malaise was reached. When individual ability to make head movements without evoking symptoms was exceeded, the derived average stressor effect (E factor) of each head movement varied directly and, in log-log terms, linearly with rotational velocity. These data provide the basis for grading individual susceptibility to Coriolis (motion) sickness with a single numerical score as well as define the high rate of change of Coriolis stressor effect as a function of rotational velocity, which may find practical application for specifying rotational rates of space stations. (Author).

Structural Elements in the Concept of Motion Sickness

Structural Elements in the Concept of Motion Sickness PDF

Author: Ashton Graybiel

Publisher:

Published: 1968

Total Pages: 48

ISBN-13:

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A slow rotation room in a laboratory environment provides an excellent instrument for the study of motion sickness because the experimenter can control not only the stressful Coriolis accelerations, but also other important procedural and environmental variables. By exploiting this control, combined with the judicious selection of experimental subjects, it was possible to confirm many previous findings and demonstrate that manifestations of disturbances in the vestibular system fall into two distinct categories. In the first category are reflex phenomena evoked by Coriolis accelerations when the head is rotated out of the plane of the room's rotation, and revealed through systems which, under natural stimulus conditions, have functional articulations with vestibular receiving areas. The symptomatology in the second category comprises an epiphenomenon superimposed on any manifestation of the first, when the unusual vestibular activity, presumably through facilitory-inhibitory processes, irradiates to cells or cell assemblies not normally stimulated. Selected experimental findings are used in defining the characteristics of manifestations in the two categories and in demonstrating the nature of the facultative linkage between the otherwise independent systems underlying manifestations in the two categories.

Rapid Vestibular Adaptation in a Rotating Environment by Means of Controlled Head Movements

Rapid Vestibular Adaptation in a Rotating Environment by Means of Controlled Head Movements PDF

Author: Ashton Graybiel

Publisher:

Published: 1968

Total Pages: 24

ISBN-13:

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Two attempts to telescope, in time, vestibular adaptation in a slow rotation room (SRR) were made to determine the easiest and quickest means of preventing the appearance of SRR sickness at a terminal velocity of 10 rpm. Three subjects in each experiment were exposed to unit increases in rotational velocity at which time they made several hundred experimenter-directed head movements. Prior to cessation of rotation standardized tasks were performed to determine the degree of transfer of adaptation acquired from the 'directed' movements. The results demonstrate that the process of homeostatic adaptation can be greatly speeded up through experimental control of head movements although a large number of 'limited' head motions must be made to ensure transfer of adaptation to general activities. Some idea was gained regarding the number and excursion of head movements required at each unit increase in rpm for adaptation and overadaptation at terminal velocity. (Author).

Modification of Vestibular Responses as a Function of Rate of Rotation about an Earth-horizontal Axis

Modification of Vestibular Responses as a Function of Rate of Rotation about an Earth-horizontal Axis PDF

Author: Manning J. Correia

Publisher:

Published: 1966

Total Pages: 28

ISBN-13:

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A study was made to compare nystagmic and subjective responses elicited at 10 RPM with responses elicited at 30 RPM when the axis of rotation was horizontal. When the same subjects were rotated about an Earth -horizontal axis at 10 and 30 RPM, the following differences in responses were noted: (1) Subjects who produced a unidirectional horizontal nystagmus throughout rotation at 10 RPM produced a reversing horizontal nystagmus after an interval (30 - 60 seconds) of rotation at 30 RPM. (2) Subjects, who gave veridical estimates of body orientation at 10 RPM, became disoriented at 30 RPM when nystagmus commenced reversing. At both 10 and 30 RPM a cyclic modulation of nystagmus was related to orientation relative to gravity. As in previous studies, sickness was produced by rotation about a horizontal axis, and a relationship between mental task and incidence of sickness was again noted. (Author).

Progressive Adaptation to Coriolis Accelerations Associated with 1-rpm Increments in the Velocity of the Slow Rotation Room

Progressive Adaptation to Coriolis Accelerations Associated with 1-rpm Increments in the Velocity of the Slow Rotation Room PDF

Author: James T. Reason

Publisher:

Published: 1969

Total Pages: 24

ISBN-13:

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The purpose of this experiment was to answer specific questions relating to the design of an adaptation schedule effective in protecting against motion sickness in a rotating environment. Ten men with normal vestibular function executed controlled head and body movements at each of ten 1-rpm step increase in the velocity of the Pensacola Slow Rotation Room. On the completion of every moment, subjects were required to indicate whether or not they had detected sensations of vestibular or somatosensory origin. At each velocity step, the movements were continued until each of 24 consecutive movements had elicited a negative response and the subject was judged to be symptom free. When this arbitrary adaptation criterion was reached, the angular velocity was increased by 1 rpm and the procedure repeated. On attaining the criterion at the terminal velocity (10 rpm), the rotation was stopped and the postrotatory phenomena were investigated using the same techniques. The principal finding was that the number of movements necessary to achieve the adaptation criterion was systematically related to the absolute level of angular velocity. Considerably more head and body movements were required to reach the same level of adaptation at faster speeds than at slower speeds, even though the size of the step increment remained constant. There was some evidence to indicate that the amount of stimulation to criterion depended upon the initial magnitude of sensation elicited by the increment. There were also wide individual differences in both the rate of adaptation and the minimum velocity necessary to evoke sensation. (Author).

Motion and Space Sickness

Motion and Space Sickness PDF

Author: George H. Crampton

Publisher: CRC Press

Published: 1990-01-17

Total Pages: 464

ISBN-13: 9780849347030

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This compendium, written by active researchers in the field, encompasses topics ranging from anatomical and physiological subjects, through analyses of stimulus characteristics, prediction of sickness, and consideration of human factors, to pharmacological and behavioral therapeutic measures for terrestrial as well as microgravity travelers. Material often found scattered in diverse journals, paper-bound proceedings of symposia, difficult-to-find laboratory reports, or included with other topics in collections having a diffuse focus, are presented here in one volume dedicated to a single theme. The critical up-to-date- reviews are a first source for researchers and research program managers as well as an essential information source for engineers and practitioners.

Changes in Subjective Estimates of Well-being During the Onset and Remission of Motion Sickness Symptomatology in the Slow Rotation Room

Changes in Subjective Estimates of Well-being During the Onset and Remission of Motion Sickness Symptomatology in the Slow Rotation Room PDF

Author: James T. Reason

Publisher:

Published: 1969

Total Pages: 28

ISBN-13:

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The onset of motion sickness is characterized by a decline in generalized feelings of well-being. In this study, an attempt was made to quantify these subjective changes during the experimental production of motion sickness in the Slow Rotation Room. A simple eleven-point rating scale was used to measure the well-being state. The nature and the time of onset of symptoms were recorded independently. Systematic relationships were obtained between the amount of stimulation required to produce the Malaise 111 endpoint and the rate of change of well-being. In general, relatively susceptible individuals showed on immediate decline in well-being at the onset of the stimulus which continued to fall sharply until the endpoint was reached. With increasing resistance to motion sickness, this point of rapid decline ('avalanche phenomenon') was proportionately delayed. The point on the rating scale at which this rapid decline began was relatively consistent across all subjects. Various positions along the well-being scale were consistently associated with specific constellations of symptoms. The recovery of well-being, following the cessation of the stimulus, appeared to be slower in individuals of low susceptibility than in those who were highly susceptible. (Author).

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