Vestibular Contributions to Spatial Memory and Hippocampal Function.

In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, vestibular loss may also cause cognitive disorders, especially spatial memory deficits, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and cortex play in spatial orientation. In this series of published studies it is shown that vestibular loss causes cognitive disorders, especially spatial memory deficits, in animals and humans, and that electrophysiological and neurochemical changes occur in the hippocampus following peripheral vestibular lesions. These deficits are not obviously due to hearing loss, problems with motor control, oscillopsia or anxiety and depression. These studies suggest that vestibular information is necessary for the normal function of the hippocampus and therefore for normal spatial memory