Ventral cochlear nucleus

Ventral cochlear nucleus
Ventral cochlear nucleus is No. 3, at upper left
Details
Identifiers
Latin	nucleus cochlearis anterior
NeuroNames	hier-719
NeuroLex ID	Ventral cochlear nucleus
Dorlands /Elsevier	n_11/12580776
TA	A14.1.04.249
FMA	54621
Anatomical terms of neuroanatomy []

In the ventral cochlear nucleus (VCN), auditory nerve fibers enter the brain via the nerve root in the VCN. The ventral cochlear nucleus is divided into the anterior ventral (anteroventral) cochlear nucleus (AVCN) and the posterior ventral (posteroventral) cochlear nucleus (PVCN). In the VCN, auditory nerve fibers bifurcate, the ascending branch innervates the AVCN and the descending branch innervates the PVCN and then continue to the dorsal cochlear nucleus. The orderly innervation by auditory nerve fibers gives the AVCN a tonotopic organization along the dorsoventral axis. Fibers that carry information from the apex of the cochlea that are tuned to low frequencies contact neurons in the ventral part of the AVCN; those that carry information from the base of the cochlea that are tuned to high frequencies contact neurons in the dorsal part of the AVCN. Several populations of neurons populate the AVCN. Bushy cells receive input from auditory nerve fibers through particularly large endings called end bulbs of Held. They contact stellate cells through more conventional boutons.

The anterior cochlear nucleus contains several cell types, which correspond fairly well with different physiological unit types. Additionally, these cell types generally have specific projection patterns.

Named due to the branching, tree-like, nature of their dendritic fields, visible using Golgi's method, they receive large end bulbs of Held from auditory nerve fibers. Bushy cells are of three subtypes that project to different target nuclei in the superior olivary complex.

Globular bushy cells project large axons to the contralateral medial nucleus of the trapezoid body (MNTB), in the superior olivary complex where they synapse onto principal cells via a single calyx of Held, and several smaller collaterals synapse ipsilaterally in the posterior (PPO) and dorsolateral periolivary (DLPO) nuclei, lateral superior olive (LSO), and lateral nucleus of the trapezoid body (LNTB); contralaterally in the dorsomedial periolivary nucleus (DMPO), ventral nucleus of the trapezoid body (VNTB), nucleus paragigantocellularis lateralis (PGL), and ventral nucleus of the lateral lemniscus (VNLL). Axons always send a collateral into the MNTB, but do not necessarily give rise to collaterals that innervate each of the other nuclei.