Vol. 280, Issue 5, G850-G857, May 2001
Modulation of gastric motor activity by a centrally acting
stimulus, circular vection, in humans
Henryk
Faas1,
Christine
Feinle1,
Paul
Enck2,
David
Grundy3, and
Peter
Boesiger1
1 Biophysics Division, Institute of Biomedical Engineering,
University and Eidgenoessisch-Technische Hochschule, 8092 Zürich,
Switzerland; 2 Department of Surgery, University of
Tübingen, 72076 Tübingen, Germany; and 3 Department
of Biomedical Science, University of Sheffield, Sheffield S10 2TN,
United Kingdom
The aims of this study were to
investigate gastric motor correlates of vection, a centrally acting
stimulus, and relate these responses to the induction of motion
sickness symptoms. Antral contractile activity and gastric volume
retained after a liquid nutrient meal (600 ml) were assessed by
magnetic resonance imaging in healthy subjects during two different
protocols. Vection was induced by an optokinetic drum, and subjects
repeatedly rated the intensity of vection and nausea on 0-10
analog scales. Vection delayed gastric emptying {99% (89-102%)
[median (interquartile ranges)] of volume retained at 28 min; control
situation: 79% (69-81%), P < 0.05}. Antral
contractile activity followed a distinct time course of rapid decrease
[
64% (72 to 59%) change from baseline activity] immediately
after onset of drum rotation followed by gradual recovery upon
withdrawal of the stimulus. No relationship was found between the
severity of nausea and inhibition of gastric emptying or antral
contractile activity. The inhibition of antral contractile activity
appears to be a good measure of the peripheral response to vection but
is probably independent of subjective symptom induction.
illusory self motion; magnetic resonance imaging
