The basilar membrane’s tapering shape enables it to sort sounds by frequency.
Evidence
The basilar membrane is responsible for carrying out a frequency analysis of input sounds. In shape, the basilar membrane is both narrow and thin at the base end of the cochlea, becoming both wider and thicker along its length to the apex, as illustrated in Figure 2.4. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 547
Categorization
Category: Causal Relationships
- DEFINE: Establishes the basilar membrane as the cochlea’s frequency-analyzing structure and its geometric basis.
- XREF: The graded-width resonator principle parallels how a piano’s strings differ in length and mass to cover pitch range.
Related
- The ear analyzes frequencies by location along the basilar membrane. (similarity 0.87)
- Basilar membrane stiffness gradients create a frequency-to-place mapping (similarity 0.87)
- Tonotopic frequency ordering persists from cochlea to auditory cortex (similarity 0.87)
- Frequency sorting in the basilar membrane can be reproduced in physical models (similarity 0.86)
- Each basilar membrane location acts as a bandpass filter tuned to a center frequency (similarity 0.86)
- The basilar membrane’s mechanics enable the inner ear’s frequency analysis (similarity 0.86)
- Broad-spectrum sounds read as louder because auditory bands integrate across the basilar membrane (similarity 0.86)
- The auditory system acts as a band-pass filter at each signal frequency. (similarity 0.85)
- The ear analyzes complex sounds by superposition of individual frequency responses (similarity 0.84)
- Frequency discrimination depends on basilar membrane displacement separation (similarity 0.84)
- Just-noticeable frequency shifts map to constant basilar distances (similarity 0.83)
- The ear functions as a bank of frequency-selective filters tuned to basilar membrane places (similarity 0.83)
- The basilar membrane’s logarithmic spacing justifies plotting auditory representations on log frequency axes (similarity 0.83)
- Basilar-membrane frequency sorting is too crude to explain our pitch discrimination (similarity 0.82)
- Hearing two tones as separate requires separate basilar membrane peaks (similarity 0.82)