Hearing-aid settings in connection to supra-threshold auditory processing deficits

Plomp (1986) described the consequences of hearing impairment in speech communication as the sum of two components: attenuation and distortion. Recent studies have shown that the sensitivity to spectro-temporal modulations (STM) might be linked to speech intelligibility in noise, suggesting that supra-threshold, or “internal”, distortions would affect both speech and STM perception similarly.

Furthermore, reduced sensitivity to STM may also affect a listener’s preference for a hearing aid (HA) compensation strategy. Here, speech intelligibility and STM sensitivity were measured in 20 hearing-impaired (HI) listeners. One group of the listeners (Group A) showed an inability to detect STM, whereas the other listeners (Group B) exhibited similar thresholds as the control group with young normal-hearing (NH) listeners.

The two HI groups participated in a perceptual evaluation experiment using multi-stimulus comparisons (MUSHRA). The audio files were processed by a HA simulator fitted to the individual hearing loss and the performance was rated in terms of four attributes: clarity, comfort, preference and listening effort.

A correlation analysis showed that clarity and preference were correlated in Group A whereas comfort and listening effort were correlated in Group B. The classification of HI listeners in auditory profiles might be valuable for efficient HA fitting.