The pinna’s low-frequency notch shifts upward in frequency as sound source elevates

Evidence

One potential solution to this problem is to provide hearing-aid users with artificially enhanced pinna cues—as if they were listening through oversized pinnas. In the present study, it was tested whether test subjects were better at discriminating spectral patterns similar to enlarged-pinna cues. The enlarged-pinna patterns were created by transposing (T) generic normal-sized pinna cues (N) one octave down, or by using the approach (W) suggested by Naylor and Weinrich (System and method for generating auditory spatial cues, United States Patent, 2011). The experiment was cast as a determination of simulated minimum audible angle (MAA) in the median saggital plane. 13 test subjects with sloping hearing loss and 11 normal-hearing test subjects participated. The normal-hearing test subjects showed similar discrimination performance with the T, W, and N-type simulated pinna cues, as expected. However, the results for the hearing-impaired test subjects showed only marginally lower MAAs with the W and T-cues compared to the N-cues, while the overall discrimination thresholds were much higher for the hearing-impaired compared to the normal-hearing test subjects. — Dijk, Pim van, Physiology, Psychoacoustics and…, 3050 (#exemplifies, via linked claim)

This study compared the ability to discriminate simulated normally-sized pinna cues with the ability to discriminate two different sets of simulated enhanced pinna cues, in a group of NH test subjects and in a group of HI test subjects, respectively. The results showed that the NH group discriminated equally well with all three sets of pinna cues, showing a mean MAA of around 10° across cue types and reference angle. In the HI group, use of W-cues improved the mean MAA from around 30° to around 20°. This improvement was significant and twice as large as the non-significant mean improvement (from around 25° to 20°) offered by the T-cues. — Dijk, Pim van, Physiology, Psychoacoustics and…, 3133 (#exemplifies, via linked claim)

Categorization

• XREF: connects to: The pinna’s folded shape encodes sound direction as spectral echoes; Hearing impairment makes fine high-frequency pinna cues imperceptible; Even enlarged pinna cues leave hearing-impaired localization far below normal — Dijk, Pim van, Physiology, Psychoacoustics and…, 3050 (+1 more)

Related

• Hearing impairment makes fine high-frequency pinna cues imperceptible (similarity 0.95)
• Even enlarged pinna cues leave hearing-impaired localization far below normal (similarity 0.91)
• Wide-cue pinna size improves MAA only for hearing-impaired listeners (similarity 0.90)
• Enhanced pinna cues only partially close the spatial-resolution gap in hearing-impaired listeners (similarity 0.89)
• Pinna spectral notch frequency increases with sound elevation in the median plane (similarity 0.88)
• Hearing loss impairs pinna-cue discrimination for vertical sound localization (similarity 0.88)
• Hearing-impaired subjects localized via pinna frequency shaping, not level differences (similarity 0.87)
• Oversized-pinna cue simulation barely improves vertical localization for hearing-impaired listeners (similarity 0.87)
• A low-frequency spectral notch in pinna cues shifts upward with elevation angle (similarity 0.87)
• The pinna’s folded shape encodes sound direction as spectral echoes (similarity 0.87)
• Enlarging the pinna improves azimuth localization only for hearing-impaired listeners (similarity 0.86)
• Hearing-impaired listeners cannot perceive fine high-frequency pinna spectral details (similarity 0.86)
• Pinna cues can be transposed one octave down for hearing-impaired listeners (similarity 0.86)
• Pinna frequency-shaping cues, not level cues, drive sound localization at typical angular thresholds (similarity 0.86)
• Down-shifted Weinrich cues improve MAA in hearing-impaired listeners by about ten degrees (similarity 0.86)

Broader Connections

• Hearing impairment makes fine high-frequency pinna cues imperceptible #complicates (0.85)
• Even enlarged pinna cues leave hearing-impaired localization far below normal #exemplifies (0.85) — Dijk, Pim van, Physiology, Psychoacoustics and…, 3050
• Enhanced pinna cues only partially close the spatial-resolution gap in hearing-impaired listeners #exemplifies (0.80) — Dijk, Pim van, Physiology, Psychoacoustics and…, 3133