Introduction
The nervus vestibularis is the vestibular nerve and is part of the vestibulocochlear nerve. This nerve is the VIII. cranial nerve.
The vestibulocochlear nerve can be divided into two parts, the cochlear nerve, i.e. the auditory nerve, and the vestibular nerve, i.e. the vestibular nerve. The function of the nerve is to transmit information from the organs of balance in the inner ear to the brain.
Anatomy
The nervus vestibularis originates in the inner ear in the so-called vestibular ganglion. A ganglion is a collection of nerve cell bodies. It makes its way together with the auditory nerve through the inner ear canal (internal auditory meatus) to reach the posterior fossa.
This common path is also called the vestibulocochlear nerve. The entry of the vestibulocochlear nerve into the posterior fossa takes place at an opening, the so-called internal acoustic porus. From here, the nerve can enter the brainstem at the cerebellar bridge angle, where it is split again into the two parts of the vestibulocochlear nerve.
The nervus vestibularis then moves to its cranial nerve nuclei, the “equilibrium nuclei” (Nuclei vestibulares) in the rhomboid brain (rhombencephalon). There are a total of four “equilibrium nuclei”, which have different names depending on their localization. There is the nucleus vestibularis superior, the nucleus vestibularis inferior, the nucleus vestibularis medialis and the nucleus vestibularis lateralis.
From here, information that has arrived via the vestibular nerve (so-called afferences) is switched and forwarded. The information from the organs of equilibrium is passed on to other areas of the brain and spinal cord. The function of the vestibular nerve can be checked by means of brainstem response audiometry, also known as BERA (brainstem evoked response audiometry).
The subject is exposed to auditory stimuli in a soundproof room via headphones. Electrodes attached to the head normally allow brain potentials to be derived after the delivery of the auditory stimuli, which are then displayed in the form of curves.
