What term describes the frequency-specific organization along the basilar membrane?

What term describes the frequency-specific organization along the basilar membrane?

• A. Tonotopic map
• B. Cochlear gradient
• C. Auditory plasticity
• D. Acoustic reflex

Answer: (A)

Tonotopy is the arrangement where different frequencies are represented at specific locations along the basilar membrane. The membrane’s stiffness changes from base to apex, so a sound’s traveling wave peaks at different places depending on frequency: high frequencies peak near the stiff base, while low frequencies peak closer to the flexible apex. This creates a spatial map where neighboring locations along the membrane correspond to neighboring frequencies, forming a frequency-specific organization that is preserved through the auditory pathway to cortex. That direct link between frequency and place makes tonotopic mapping the exact term for this concept. The other choices refer to different phenomena: a general term for gradients that isn’t the standard description of frequency-to-place organization, plastic changes with experience, or a reflex not about frequency mapping.

Tonotopy is the arrangement where different frequencies are represented at specific locations along the basilar membrane. The membrane’s stiffness changes from base to apex, so a sound’s traveling wave peaks at different places depending on frequency: high frequencies peak near the stiff base, while low frequencies peak closer to the flexible apex. This creates a spatial map where neighboring locations along the membrane correspond to neighboring frequencies, forming a frequency-specific organization that is preserved through the auditory pathway to cortex. That direct link between frequency and place makes tonotopic mapping the exact term for this concept. The other choices refer to different phenomena: a general term for gradients that isn’t the standard description of frequency-to-place organization, plastic changes with experience, or a reflex not about frequency mapping.