Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Adaptation to Coriolis Accelerations PDF full book. Access full book title Adaptation to Coriolis Accelerations by James T. Reason. Download full books in PDF and EPUB format.
Author: James T. Reason Publisher: ISBN: Category : Acceleration (Physiology) Languages : en Pages : 24
Book Description
The problem was to determine how adaptation to Coriolis accelerations, acquired through controlled head movements in a room rotating in one direction, transfers to the opposite direction as a consequence of the stimulus mode during an intervening period at zero velocity. Under one experimental condition the subjects continued to make the same head movements as those used to acquire perrotational adaptation, thus evoking postrotational responses opposite in sign but similar in quality to those experienced during the initial period of rotation. In the other, mechanical restraints were applied to the head and torso for an equivalent period of time. Subjects who performed the head motion activity during the intervening static period were able to adapt more rapidly to the second (opposite) direction of rotation than to the first. In addition, the intervening activity appeared to confer some immunity to motion sickness during the second direction of rotation. Postrotational effects following the second direction of rotation were less severe and of shorter duration than those experienced following the initial period of rotation. The opposite findings were obtained for those subjects who remained immobilized during the intervening period at zero velocity. (Author).
Author: James T. Reason Publisher: ISBN: Category : Acceleration (Physiology) Languages : en Pages : 24
Book Description
The problem was to determine how adaptation to Coriolis accelerations, acquired through controlled head movements in a room rotating in one direction, transfers to the opposite direction as a consequence of the stimulus mode during an intervening period at zero velocity. Under one experimental condition the subjects continued to make the same head movements as those used to acquire perrotational adaptation, thus evoking postrotational responses opposite in sign but similar in quality to those experienced during the initial period of rotation. In the other, mechanical restraints were applied to the head and torso for an equivalent period of time. Subjects who performed the head motion activity during the intervening static period were able to adapt more rapidly to the second (opposite) direction of rotation than to the first. In addition, the intervening activity appeared to confer some immunity to motion sickness during the second direction of rotation. Postrotational effects following the second direction of rotation were less severe and of shorter duration than those experienced following the initial period of rotation. The opposite findings were obtained for those subjects who remained immobilized during the intervening period at zero velocity. (Author).
Author: James T. Reason Publisher: ISBN: Category : Acceleration (Physiology) Languages : en Pages : 24
Book Description
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).
Author: James T. Reason Publisher: ISBN: Category : Languages : en Pages : 21
Book Description
The problem was to determine how adaptation to Coriolis accelerations, acquired through controlled head movements in a room rotating in one direction, transfers to the opposite direction as a consequence of the stimulus mode during an intervening period at zero velocity. Under one experimental condition the subjects continued to make the same head movements as those used to acquire perrotational adaptation, thus evoking postrotational responses opposite in sign but similar in quality to those experienced during the initial period of rotation. In the other, mechanical restraints were applied to the head and torso for an equivalent period of time. Subjects who performed the head motion activity during the intervening static period were able to adapt more rapidly to the second (opposite) direction of rotation than to the first. In addition, the intervening activity appeared to confer some immunity to motion sickness during the second direction of rotation. Postrotational effects following the second direction of rotation were less severe and of shorter duration than those experienced following the initial period of rotation. The opposite findings were obtained for those subjects who remained immobilized during the intervening period at zero velocity. (Author).
Author: James T. Reason Publisher: ISBN: Category : Languages : en Pages : 21
Book Description
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).
Author: A. J. Benson Publisher: ISBN: Category : Languages : en Pages : 20
Book Description
A theoretical model for progressive adaptation to Coriolis accelerations is described. Thirteen subjects were tested under procedures identical to those using fixed velocity increments described in previous studies, but in this instance diminishing velocity increments, with an initial step of 3 rev/min were used. The findings provide positive, but as yet, limited support for the theoretical model described. (Author).
Author: James T. Reason Publisher: ISBN: Category : Coriolis force Languages : en Pages : 20
Book Description
The problem was to obtain a quantitative estimate of the degree of adaptation acquired as the result of different amounts of Coriolis stimulation. Subjects executed a predetermined number of controlled 90 deg. head motions at 5 rpm in the slow rotation room. Three measures of adaptation were used: (1) the number of perrotatory head movements evoking sensations due to the Coriolis acceleration, (2) the direction and duration of the Coriolis oculogyral illusion both during and immediately after the period of rotation, and (3) the number of postrotatory sensations producing some detectable after-sensation. The first measure was included to provide an indication of individual differences in adaptability; the remaining two were designed to reveal treatment effects. Six conditions of exposure, ranging from 30 to 180 sequences of eight motions each, produced no measurable differences in the degree of adaptation acquired. A positive and significant correlation was obtained between the number of perrotatory motions evoking a Coriolis reaction (irrespective of the total number of sequences executed) and the number of postrotatory motions producing an after-sensation. In a second experiment, the range of exposures was limited to 5, 10, 15, 20, and 25 sequences. Only the shortest exposure produced a measure of adaptation that was significantly less than that in the other conditions. (Author).
Author: J. T. Reason Publisher: ISBN: Category : Languages : en Pages : 46
Book Description
Three groups were exposed to stepwise increments of Coriolis accelerations in three visual modes: Internal Visual Reference (IVR), External Visual Reference (EVR), and Vision-Absent (VA). The subjects in the IVR condition required significantly greater amounts of stimulus exposure to neutralise their illusory subjective reactions. They also suffered a greater loss of well-being, and a more marked incidence of motion sickness than did subjects in the EVR and VA conditions. The 30 subjects who completed the first session were exposed to the same graded cross-coupled stimulation one week later. This time, however, all the subjects were retested under the IVR conditions. All three groups showed some positive transfer of adaptation from Session I to Session II, but only the IVR-IVR combination required significantly fewer head motions to achieve the same level of adaptation on the second occasion. Taken overall, however, the most efficient and least distrubing route to adaptation at the completion of Session II was via the VA-IVR combination. (Author).
Author: James T. Reason Publisher: ISBN: Category : Languages : en Pages : 16
Book Description
The problem was to obtain a quantitative estimate of the degree of adaptation acquired as the result of different amounts of Coriolis stimulation. Subjects executed a predetermined number of controlled 90 deg. head motions at 5 rpm in the slow rotation room. Three measures of adaptation were used: (1) the number of perrotatory head movements evoking sensations due to the Coriolis acceleration, (2) the direction and duration of the Coriolis oculogyral illusion both during and immediately after the period of rotation, and (3) the number of postrotatory sensations producing some detectable after-sensation. The first measure was included to provide an indication of individual differences in adaptability; the remaining two were designed to reveal treatment effects. Six conditions of exposure, ranging from 30 to 180 sequences of eight motions each, produced no measurable differences in the degree of adaptation acquired. A positive and significant correlation was obtained between the number of perrotatory motions evoking a Coriolis reaction (irrespective of the total number of sequences executed) and the number of postrotatory motions producing an after-sensation. In a second experiment, the range of exposures was limited to 5, 10, 15, 20, and 25 sequences. Only the shortest exposure produced a measure of adaptation that was significantly less than that in the other conditions. (Author).
Author: Ashton Graybiel Publisher: ISBN: Category : Motion sickness Languages : en Pages : 24
Book Description
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).
Author: James T. Reason
Author: James T. Reason
Author: James T. Reason
Author: James T. Reason
Author: James T. Reason
Author: A. J. Benson
Author: James T. Reason
Author: J. T. Reason
Author: J. T. Reason
Author: James T. Reason
Author: Ashton Graybiel