Effect of hypoxia on motion sickness induced by optokinetic stimulation

The purpose of this experiment was to study the effect of hypoxia on motion sickness (MS) induced by optokinetic stimulation and to observe its character and principle. Twenty healthy male subjects aged 18-25 years received optokinetic stimulus (OS) and hypoxic-optokinetic stimulus (HOS) according to the "Latin Square" arrangement and "Self-control" methods. Motion sickness symptoms (MSS) and optokinetic horizontal nystagmus (OKHN) were recorded and analysed. The results indicated: (1) MS average score for HOS was higher than that for OS (P<0.001); (2) Slow phase velocity(SPV) of OKHN in HOS was lower than that in OS (P<0.001). The results clearly showed that moderate hypoxia could deteriorate the MS induced by OS. It provided a method for the screening of MS sensitivity.