The modiolus is a conical shaped central axis in the cochlea. The modiolus consists of spongy bone and the cochlea turns approximately 2.75 times around the central axis in humans.^[1] The cochlear nerve, as well as spiral ganglion is situated inside it. The cochlear nerve conducts impulses from the receptors located within the cochlea.

Modiolus
Interior of right osseous labyrinth. (Modiolus not labeled, but is represented at the axis of the spiral of the cochlea at the right.)
Details
Identifiers
Latin	modiolus, columella cochleae
TA98	A15.3.03.038
TA2	6980
FMA	61278
Anatomical terminology [edit on Wikidata]

The picture shows the osseous labyrinth. The modiolus is not labeled; it's at the axis of the spiral of the cochlea.