What is the organ of Corti and where is it located?

• A. The organ of Corti is the sensory organ for hearing, containing hair cells in the cochlea of the inner ear
• B. It is in the semicircular canals
• C. It is in the utricle and saccule
• D. It is in the tympanic membrane

Answer: (A)

The organ of Corti is the sensory organ for hearing, and it sits on the basilar membrane inside the cochlea of the inner ear. It contains the hair cells that convert mechanical vibrations from sound into neural signals. When sound creates waves in the fluid of the cochlea, the basilar membrane moves and the hair cells’ stereocilia deflect against the overlying tectorial membrane, opening ion channels and releasing neurotransmitters to drive the auditory nerve. The cochlea is a spiral, fluid-filled structure, and the organ of Corti is specifically within the cochlear duct along the basilar membrane. In contrast, the semicircular canals are involved in balance and detect rotational movement, the utricle and saccule detect linear acceleration and head position, and the tympanic membrane (eardrum) vibrates to transfer sound energy to the inner ear.