The spiral (cochlear) ganglion is a group of neuron cell bodies in the modiolus, the conical central axis of the cochlea.

Neurons whose cell bodies lie in the spiral ganglion are strung along the bony core of the cochlea, and send fibers (axons) into the central nervous system (CNS).

Their dendrites make synaptic contact with the base of hair cells, and their axons are bundled together to form the auditory portion of eighth cranial nerve.

[4] The rudiment of the cochlear nerve appears about the end of the third week as a group of ganglion cells closely applied to the cephalic edge of the auditory vesicle.

The axons of neurons in the spiral ganglion travel to the brainstem, forming the cochlear nerve.