How is sound transduced into neural signals?

How is sound transduced into neural signals?

• A. By hair cells in semicircular canals.
• B. Within the cochlear region of the inner ear.
• C. By mechanically stimulating the tympanic membrane only.
• D. By photoreceptors in retina.

Answer: (B)

Sound transduction into neural signals happens in the cochlea of the inner ear. When air vibrations reach the inner ear, the tympanic membrane and the ossicles mechanically amplify the sound and push oval window motion into the fluid of the cochlea. There, hair cells along the basilar membrane convert this mechanical motion into electrical signals. The stereocilia of these hair cells bend in response to the motion, opening mechanically gated ion channels. This creates a receptor potential and causes neurotransmitter release onto afferent fibers of the auditory nerve, generating action potentials that travel to the brain for sound perception. The vestibular hair cells in the semicircular canals detect head movement (not sound), and photoreceptors in the retina respond to light, so those are not involved in auditory transduction.

Sound transduction into neural signals happens in the cochlea of the inner ear. When air vibrations reach the inner ear, the tympanic membrane and the ossicles mechanically amplify the sound and push oval window motion into the fluid of the cochlea. There, hair cells along the basilar membrane convert this mechanical motion into electrical signals. The stereocilia of these hair cells bend in response to the motion, opening mechanically gated ion channels. This creates a receptor potential and causes neurotransmitter release onto afferent fibers of the auditory nerve, generating action potentials that travel to the brain for sound perception. The vestibular hair cells in the semicircular canals detect head movement (not sound), and photoreceptors in the retina respond to light, so those are not involved in auditory transduction.