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Publication AbstractsGastric Myoelectric Activity During Low Frequency OscillationSharon R. Holmes, B.A., Ph.D., and Michael J. Griffin, B.Sc., Ph.D.Aviat Space Environ Med 2000; 71:420-5 AbstractBackground: The normal 3 cycles per minute (3 c/m) resting activity of the stomach has been reported to shift into the range of 4-9 c/m (tachyarrhythmia) in subjects with symptoms of motion sickness. Previous studies have provoked motion sickness with an optokinetic stimulus and have not normally reported changes relative to a control condition. The present experiment investigated changes in the electrogastrogram (EGG) during a control condition and during exposure to 0.125 Hz off-axis yaw oscillation of the body. Methods: There were 16 male subjects who participated in the two conditions 1 wk apart. The electrogastrogram, respiration rate and subjective ratings of sickness were monitored throughout both conditions. Spectral analysis of the EGG time histories provided measures of 3 c/m power and tachyarrhythmia power, which were also expressed as a percentages of EGG power over the total EGG frequency range (0.04 to 0.16 Hz.). The median frequency of the EGG over this bandwidth was also calculated. Results: During motion exposure, the median frequency of the EGG and the percentage tachyarrhythmia power increased and the percentage 3 c/m power decreased relative to a pre-exposure baseline period and relative to the static control condition. Conclusions: Low frequency off-axis yaw oscillations disrupted the normal resting gastric myoelectric activity relative to a control condition.Keywords: electrogastrogram, motion sickness, off-axis oscillation. Information on subscribing, and on obtaining copies of an article or of an entire issue. Table of Contents for Volume 71, Number 4 of the ASME journal.
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