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Acute effects of whole-body vibration: stabilography and electrogastrography
JournalofSound and Vibration (1989) 128(3), 537-539
HUMAN
RESPONSE
TO VIBRATION
ABSTRACTS Prepared by M. J. Grifin and J. Grifin, Human Factors Research Unit, Institute of Sound and Vibration Research, University of Southampton, Southampton SO9 5 NH, England
A. Kjellberg and B-O. Wikstriim 1987 Scandinavian Journal of Work and Environmental Health 13, 243-246. Acute effects of whole-body vibration: stabilography and electrogastrography. (4 pages, 2 figures, 0 tables, 18 references) (in English) Authors’ Abstract. The influence of whole-body vibration on postural control and stomach motility was investigated. Fifteen subjects were exposed to two vibration signais (3 and 6 Hz random) while sitting for 1 h on a vibration simulator. A control situation, i.e., sitting for 1 h without vibration, was also included. Stabilographic recordings before and 1 and 15 min after the sitting showed that exposure to these frequencies had no effect on postural control. Electrogastrographic (EGG) measurements before and during the sitting showed that, for 3 Hz, there was an initial increase in activity which decreased towards normal values. For 6 Hz there was a significant increase in activity for EGG frequencies of 0.05 and O-13 Hz. The results imply that stomach motility can be affected by whole-body vibration in certain frequency ranges. Topics: Physiological Eficts (postural function); Perceptual Mechanisms (orientation); Complex
Vibration
(random).
J.-K. Huang and L. R. Young 1987 Aviation, Space and Environmental Medicine !58( 12), 1197-1204. Influence of visual and motion cues on manual lateral stabilization. (8 pages, 7 figures, 0 tables, 26 references) (in English) Authors’ Abstract. The ability of humans to detect and control their own lateral acceleration was measured by means of a closed-loop nulling task. Wide-field moving visual cues enhanced the operator’s performance in nulling self-motion, especially at lower frequencies. Even visual cues, fixed relative to the operator, resulted in performance improvement relative to self-motion nulling in the dark. Describing function (frequency response) data was obtained for random acceleration conditions consisting of the visual field fixed relative to the laboratory, fixed relative to the subject, moving at constant velocity relative to the subject, and in the dark. The describing function data was corrected for the dynamics of operator manual control strategy. The resulting frequency responses were used to develop a linear model of self-motion detection which required a lead term of 1a5 rad s-’ to be added to the existing model in order to match the higher sensitivity at higher frequencies. Topics: Perceptual Mechanisms (proprioception, orientation, vestibular, vision); Vibration Sense (general).
D. Fucci, D. Harris, L. Petrosino and E. Randolph-Tyler 1987 Perceptual and Motor Skills Effects of aging on responses to suprathreshold lingual vibrotactile stimulation. (12 pages, 4 figures, 2 tables, 22 references) (in English) 64, 683-694.
537 0022-460X/89/030537+03
%03.00/O
@
1989 Academic
Press Limited
HUMAN
RESPONSE
TO VIBRATION
ABSTRACTS Prepared by M. J. Grifin and J. Grifin, Human Factors Research Unit, Institute of Sound and Vibration Research, University of Southampton, Southampton SO9 5 NH, England
A. Kjellberg and B-O. Wikstriim 1987 Scandinavian Journal of Work and Environmental Health 13, 243-246. Acute effects of whole-body vibration: stabilography and electrogastrography. (4 pages, 2 figures, 0 tables, 18 references) (in English) Authors’ Abstract. The influence of whole-body vibration on postural control and stomach motility was investigated. Fifteen subjects were exposed to two vibration signais (3 and 6 Hz random) while sitting for 1 h on a vibration simulator. A control situation, i.e., sitting for 1 h without vibration, was also included. Stabilographic recordings before and 1 and 15 min after the sitting showed that exposure to these frequencies had no effect on postural control. Electrogastrographic (EGG) measurements before and during the sitting showed that, for 3 Hz, there was an initial increase in activity which decreased towards normal values. For 6 Hz there was a significant increase in activity for EGG frequencies of 0.05 and O-13 Hz. The results imply that stomach motility can be affected by whole-body vibration in certain frequency ranges. Topics: Physiological Eficts (postural function); Perceptual Mechanisms (orientation); Complex
Vibration
(random).
J.-K. Huang and L. R. Young 1987 Aviation, Space and Environmental Medicine !58( 12), 1197-1204. Influence of visual and motion cues on manual lateral stabilization. (8 pages, 7 figures, 0 tables, 26 references) (in English) Authors’ Abstract. The ability of humans to detect and control their own lateral acceleration was measured by means of a closed-loop nulling task. Wide-field moving visual cues enhanced the operator’s performance in nulling self-motion, especially at lower frequencies. Even visual cues, fixed relative to the operator, resulted in performance improvement relative to self-motion nulling in the dark. Describing function (frequency response) data was obtained for random acceleration conditions consisting of the visual field fixed relative to the laboratory, fixed relative to the subject, moving at constant velocity relative to the subject, and in the dark. The describing function data was corrected for the dynamics of operator manual control strategy. The resulting frequency responses were used to develop a linear model of self-motion detection which required a lead term of 1a5 rad s-’ to be added to the existing model in order to match the higher sensitivity at higher frequencies. Topics: Perceptual Mechanisms (proprioception, orientation, vestibular, vision); Vibration Sense (general).
D. Fucci, D. Harris, L. Petrosino and E. Randolph-Tyler 1987 Perceptual and Motor Skills Effects of aging on responses to suprathreshold lingual vibrotactile stimulation. (12 pages, 4 figures, 2 tables, 22 references) (in English) 64, 683-694.
537 0022-460X/89/030537+03
%03.00/O
@
1989 Academic
Press Limited