Which theory posits that pitch is coded by the location on the basilar membrane that vibrates most?

Which theory posits that pitch is coded by the location on the basilar membrane that vibrates most?

• A. Place theory
• B. Frequency theory
• C. Opponent-process theory
• D. Gate-control theory

Answer: (A)

Pitch is coded by the location along the basilar membrane that vibrates most, a principle called place coding. The basilar membrane is arranged tonotopically, meaning different parts respond best to different frequencies: the base (closest to the middle ear) is stiff and resonates with high frequencies, while the apex (farther from the middle ear) is more flexible and resonates with low frequencies. The hair cells at the spot that vibrates the strongest convert those vibrations into neural signals sent along the auditory nerve to the brain, creating a neural representation of pitch based on where the peak stimulation occurs. This spatial mapping is what lets us perceive different pitches from different frequencies. The other ideas describe different aspects of sound processing. Frequency theory suggests pitch comes from the rate of nerve-fiber firing matching the sound’s frequency, which works for lower pitches but doesn’t explain high-pidelity pitch perception as well as place coding. Opponent-process and gate-control theories relate to color vision and pain processing, respectively, and don’t address how pitch is coded in the inner ear.

Pitch is coded by the location along the basilar membrane that vibrates most, a principle called place coding. The basilar membrane is arranged tonotopically, meaning different parts respond best to different frequencies: the base (closest to the middle ear) is stiff and resonates with high frequencies, while the apex (farther from the middle ear) is more flexible and resonates with low frequencies. The hair cells at the spot that vibrates the strongest convert those vibrations into neural signals sent along the auditory nerve to the brain, creating a neural representation of pitch based on where the peak stimulation occurs. This spatial mapping is what lets us perceive different pitches from different frequencies.

The other ideas describe different aspects of sound processing. Frequency theory suggests pitch comes from the rate of nerve-fiber firing matching the sound’s frequency, which works for lower pitches but doesn’t explain high-pidelity pitch perception as well as place coding. Opponent-process and gate-control theories relate to color vision and pain processing, respectively, and don’t address how pitch is coded in the inner ear.