Perception of speech in cartilage conduction.

Area of Science:

• Audiology
• Biomedical Engineering
• Speech Perception Research

Background:

• Cartilage conduction (CC) offers a novel method for sound transmission via aural cartilage with minimal pressure.
• Potential applications include developing new hearing aid technologies.
• Limited research exists on speech recognition using CC, necessitating further investigation.

Purpose of the Study:

• To measure and compare speech recognition performance using cartilage conduction (CC) against traditional air conduction (AC) and bone conduction (BC).
• To evaluate the impact of earplugs on CC speech recognition.
• To identify factors influencing CC speech perception.

Main Methods:

• Speech recognition tests were conducted on nine normal-hearing volunteers.
• Performance-intensity functions were measured for AC, BC, and CC.
• Testing was performed both with and without an inserted earplug.

Main Results:

• Without earplugs, CC showed comparable speech recognition to AC and BC.
• With earplugs, CC exhibited a decrease in maximum speech recognition scores and a biased emphasis on low-frequency sounds.
• Performance-intensity functions for CC did not shift parallelly with earplug insertion, unlike AC and BC.

Conclusions:

• The reduced speech recognition with earplugs in CC is attributed to biased frequency composition.
• Adjusting the frequency characteristics of CC audio signals can potentially enhance speech recognition.
• Further research into frequency equalization for CC devices is warranted.