Vestibular Disorders In Fourth Ventricle Lesions: Experimental Studies in the Cat

Abstract

There are extensive experimental data regarding disorders of vestibular reflexes following lesions in the central nervous system of animals. We will consider only the data concerning the relationship between the vestibular system and the nodulus of the cerebellum. The relationships have been established by numerous anatomical, electrophysiological, and behavioral studies which can be found in the work of Jansen and Brodal,¹ Dow and Moruzzi,² Brodal et al,³ Spiegel and Sommer,⁴ and others.^5-7 The experimental evidence associates a lesion of the nodulus with a neurological disorder characterized by hyperactive responses to vestibular stimulation, positional nystagmus of various types, and disequilibrium without cerebellar ataxia.^2,6-10 In man, the clinical data are usually more complex, probably because the signs resulting from damage to one structure may be altered or masked by, or added to, signs resulting from damage to neighboring structures. In general, the information provided by several