Basilar membrane stiffness gradients create a frequency-to-place mapping

Evidence

The action of the basilar membrane can be thought of as being equivalent to a large number of overlapping band-pass filters, or a “bank” of band-pass filters, each responding to a particular band of frequencies (see Chapter 1). Based on the idealized filter response curve shape in Figure 2.10(a), an illustration of the nature of this bank of filters is given in Figure 2.10(b). Each filter has an asymmetric shape to its response, with a steeper roll-off on the high-frequency side than on the lowfrequency side; the bandwidth of a particular filter is given by the critical bandwidth (see Figure 2.8) for any particular center frequency. It is not possible to be particularly exact with regard to the extent to which the filters overlap. A common practical compromise, for example, in studio third octave graphic equalizer filter banks, is to overlap adjacent filters at the −3 dB points on their response curves. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 595 (#expands, via linked claim)

Whether or not two components that are of similar amplitude and close together in frequency can be discriminated depends on the extent to which the basilar membrane displacements, due to each of the two components, are clearly separated. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 573 (#expands, via linked claim)

Categorization

• XREF: connects to: Just-noticeable frequency shifts map to constant basilar distances — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 929; Frequency sorting in the basilar membrane can be reproduced in physical models; Frequency discrimination depends on basilar membrane displacement separation — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 573 (+6 more)

Related

• Frequency sorting in the basilar membrane can be reproduced in physical models (similarity 0.95)
• The basilar membrane’s mechanics enable the inner ear’s frequency analysis (similarity 0.95)
• Frequency discrimination depends on basilar membrane displacement separation (similarity 0.94)
• Each basilar membrane location acts as a bandpass filter tuned to a center frequency (similarity 0.92)
• Broad-spectrum sounds read as louder because auditory bands integrate across the basilar membrane (similarity 0.90)
• Basilar membrane displacement produces an asymmetric filter response across frequency. (similarity 0.89)
• Just-noticeable frequency shifts map to constant basilar distances (similarity 0.88)
• Tonotopic frequency ordering persists from cochlea to auditory cortex (similarity 0.88)
• The auditory system acts as a band-pass filter at each signal frequency. (similarity 0.88)
• The basilar membrane’s tapering shape enables it to sort sounds by frequency. (similarity 0.87)
• Hearing two tones as separate requires separate basilar membrane peaks (similarity 0.87)
• The ear analyzes frequencies by location along the basilar membrane. (similarity 0.86)
• The ear functions as a bank of frequency-selective filters tuned to basilar membrane places (similarity 0.86)
• The basilar membrane’s fixed-spread frequency resolution shrinks relative bandwidth as frequency rises (similarity 0.84)
• Place theory claims pitch is encoded by basilar membrane position (similarity 0.84)

Broader Connections

• Frequency discrimination depends on basilar membrane displacement separation #expands (0.85) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 573
• The basilar membrane’s mechanics enable the inner ear’s frequency analysis #expands (0.85)
• Each basilar membrane location acts as a bandpass filter tuned to a center frequency #expands (0.85) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 595
• Place theory claims pitch is encoded by basilar membrane position #corroborates (0.82)
• Basilar membrane displacement produces an asymmetric filter response across frequency. #expands (0.80)
• Tonotopic frequency ordering persists from cochlea to auditory cortex #expands (0.80)
• Broad-spectrum sounds read as louder because auditory bands integrate across the basilar membrane #expands (0.72)