Lateral vestibular nucleus
The axons bifurcate as they enter the posterior longitudinal bundle,
- the ascending branches send terminals and collaterals to the motor nuclei of the abducens, trochlear and oculomotor nerves, and are concerned in coördinating the movements of the eyes with alterations in the position of the head;
- the descending branches pass down in the posterior longitudinal bundle into the anterior funiculus of the spinal cord as the vestibulospinal fasciculus (anterior marginal bundle) and are distributed to motor nuclei of the anterior column by terminals and collaterals.
Other fibers are said to pass directly to the vestibulospinal fasciculus without passing into the posterior longitudinal bundle.
The fibers which pass into the vestibulospinal fasciculus are intimately concerned with equilibratory reflexes.
Other axons from Deiters’s nucleus are supposed to cross and ascend in the opposite medial lemniscus to the ventro-lateral nuclei of the thalamus; still other fibers pass into the cerebellum with the inferior peduncle and are distributed to the cortex of the vermis and the roof nuclei of the cerebellum; according to Cajal they merely pass through the nucleus fastigii on their way to the cortex of the vermis and the hemisphere.