In the organ of Corti, the large majority (about 90 percent) of primary afferent fibres of the cochlear nerve arise from type I spiral ganglion neurons and terminate on which structures?

• A Outer hair cells of all three rows
• B Inner hair cells ✓
• C Inner phalangeal cells
• D Outer hair cells of the basal turn only

Explanation

Despite numbering only about 3500 per cochlea against roughly 12000 outer hair cells, the inner hair cells receive about 90 percent of all afferent fibres, each contacting many type I ganglion dendrites. This fits their role as the true sensory transducers. Outer hair cells are innervated mostly by efferent fibres of the olivocochlear bundle, which is why option A fails.

Reference: Ganong Review of Medical Physiology, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.