Audibility is the greatest factor in hearing-loss communication difficulty

Evidence

Hearing loss has been shown to reduce speech understanding in spatialized multitalker listening situations, leading to the common belief that spatial processing is disrupted by hearing loss. This paper describes related studies from three laboratories that explored the contribution of reduced target audibility to this deficit. All studies used a stimulus configuration in which a speech target presented from the front was masked by speech maskers presented symmetrically from the sides. Together these studies highlight the importance of adequate stimulus audibility for optimal performance in spatialized speech mixtures and suggest that reduced access to target speech information might explain a substantial portion of the “spatial” deficit observed in listeners with hearing loss. — Dijk, Pim van, Physiology, Psychoacoustics and…, 1719 (#corroborates, via linked claim)

In short, a level corresponding to 60 dB SPL(C) free-field was selected as the presentation level to be used with NH test subjects. For the HI test subjects, it was then ensured that in each one-third octave band the RMS level of the stimulus was at least 15 dB above hearing threshold before pinna-cue shaping. The required gain was added by designing an IIR filter in the test software to shape the stimulus. — Dijk, Pim van, Physiology, Psychoacoustics and…, 3052 (#expands, via linked claim)

Categorization

• XREF: connects to: The human auditory system is the hardest link in the communication chain. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 120; Most of the SRM deficit in hearing-impaired listeners stems from reduced audibility — Dijk, Pim van, Physiology, Psychoacoustics and…, 1740; Hearing aids must preserve adequate signal-to-noise ratio across varied scenarios (+4 more)

Broader Connections

• Reduced target audibility, not spatial processing loss, explains much of the hearing-loss speech deficit #corroborates (0.95) — Dijk, Pim van, Physiology, Psychoacoustics and…, 1719
• Glimpses can fall below audibility threshold for hearing-impaired listeners #expands (0.80)
• Hearing-loss compensation boosts stimulus level 15 dB above threshold per band #expands (0.75) — Dijk, Pim van, Physiology, Psychoacoustics and…, 3052
• Hearing loss impairs frequency selectivity beyond what stimulus level differences explain. #qualifies (0.75) — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 558