Editing Auditory system (section)

==== Neurons ====
{{Main|Hair cell#Neural connection|l1=Hair cell neural connection}}

Afferent neurons innervate cochlear inner hair cells, at synapses where the neurotransmitter [[glutamate]] communicates signals from the hair cells to the dendrites of the primary auditory neurons.

There are far fewer inner hair cells in the cochlea than afferent nerve fibers – many auditory nerve fibers innervate each hair cell. The neural dendrites belong to neurons of the [[auditory nerve]], which in turn joins the [[vestibular nerve]] to form the [[vestibulocochlear nerve]], or [[cranial nerve]] number VIII.<ref>{{Cite web |url=http://www.meddean.luc.edu/lumen/meded/GrossAnatomy/h_n/cn/cn1/cn8.htm |title=Meddean – CN VIII. Vestibulocochlear Nerve |access-date=2007-10-27 |archive-date=2012-10-06 |archive-url=https://web.archive.org/web/20121006084020/http://www.meddean.luc.edu/lumen/MedEd/grossanatomy/h_n/cn/cn1/cn8.htm |url-status=live }}</ref>
The region of the basilar membrane supplying the inputs to a particular afferent nerve fibre can be considered to be its [[receptive field]].

Efferent projections from the brain to the cochlea also play a role in the perception of sound, although this is not well understood. Efferent synapses occur on outer hair cells and on afferent (towards the brain) dendrites under inner hair cells