What are the central vestibular pathways?
The vestibular nerve projects to the vestibular nuclei in the rostral medulla. From there, vestibulospinal tracts descend to cervical, thoracic, and lumbosacral levels of the spinal cord.
Therefore, vestibular signals are involved in mediating balance during standing and walking. Note, however, balance is not only controlled by the vestibular system. It is a multifactorial function. In particular, visual signals have been recorded in the vestibular nuclei.
Vision is known to have a strong influence on balance, and patients with vestibular impairments may be particularly sensitive to both real and apparent visual motion.
From the vestibular nuclei pathways project to the several regions of the cerebellum: the dentate nuclei, flocculus, nodulus, and ventral uvula. Inhibitory pathways project back to the vestibular nuclei.
Those pathways are largely involved in mediating eye movements, especially the VOR, controlled by projections from the vestibular nuclei via the medial longitudinal fasciculus to the nuclei of cranial nerves III, IV, and VI.
Pathways also project rostrally via the medial geniculate and ventroposterior inferior nuclei of the thalamus to the small vestibular cortex in the parieto-insular cortex and posterior lateral sulcus.
That area is probably involved in spatial orientation. Pathways from the vestibular nuclei also project to the nucleus tractus solitarius, the parabrachial complex, and the vagus nerve to mediate vasovagal responses.
