Effects of vestibular cerebellum lesion on motion sickness in rats

The importance of the vestibular apparatus in the development of motion sic kness is widely accepted, although the role of the vestibular cerebellum re mains controversial. We examined the effects of vestibular cerebellum lesio n on the development of motion sickness in rats. Rats do not vomit, but the behaviour known as "pica", the eating of non-nutritive substances, such as kaolin, can be used as an index of motion sickness. A 2 h load of hypergra vity induced pica in rats, indicating that they suffered from motion sickne ss. Pica was induced by hypergravity load even after surgical lesion to the bilateral cerebellar flocculus or to the cerebellar vermis. We concluded t hat the vestibular cerebellum was not essential in the development of motio n sickness in rats.