Spiral ganglion cells

Neurons are in modiolus- organized tonotopically with cochlea low tones at apex.
Peripheral nerve projections- enters organ of Corti through the bony spiral lamina; 95% go to the inner HC row without branching. 20-40 afferent fibers innervate each hair cell as single axons.
5% of fibers cross through the tunnel of Corti and go to outer row of HC’s but are offset radially by 0.6 mm for optimum frequency.