Environmental noise reduction configuration: Effects on preferences, satisfaction, and speech understanding

Area of Science:

• Audiology
• Signal Processing
• Human-Computer Interaction

Background:

• Environmental noise reduction (ENR) algorithms aim to improve speech intelligibility and listening comfort for individuals with hearing impairments.
• Different ENR configurations, varying in gain reduction and noise adaptivity, may impact user experience differently.

Purpose of the Study:

• To investigate the effects of four environmental noise reduction (ENR) algorithm configurations on user preferences, speech understanding, and satisfaction in hearing-impaired individuals.
• To compare a strong, flat gain reduction versus a milder, speech-importance-function-shaped gain reduction.
• To evaluate the impact of constant versus variable (noise-level-dependent) gain reduction on user experience.

Main Methods:

• Ten hearing-impaired participants blindly compared pairs of ENR configurations in real-world settings.
• Preferences were recorded, and Sentence Reception Thresholds (SRTs) were measured in quiet and noisy conditions.
• Participant satisfaction with speech in noise was rated, assessing listening comfort, ease of understanding, and sound quality.

Main Results:

• Half of the participants preferred the MildSII (speech-importance-function-shaped) ENR, while the other half preferred the StrongFlat (strong, flat gain reduction) configuration.
• All participants preferred the Variable (noise-adaptive) ENR over the Constant (invariant) configuration.
• The preferred ENR configuration was favored over no ENR in 90% of responses, significantly improving satisfaction for listening comfort, ease of speech understanding, and sound quality.

Conclusions:

• Environmental noise reduction (ENR) algorithms significantly enhance user satisfaction for hearing-impaired individuals, particularly in terms of listening comfort and speech understanding.
• Noise-adaptive ENR configurations (Variable) are generally preferred over static ones (Constant).
• While no statistically significant effect on SRTs was found, a clinically significant improvement of up to 2 dB cannot be excluded, suggesting potential benefits for speech perception.