Do Room Acoustics Affect the Amplitude of Sound-Field Auditory Steady-State Responses?

Area of Science:

• Audiology
• Acoustics
• Neuroscience

Background:

• Sound-field auditory steady-state response (ASSR) is crucial for objective hearing aid fitting validation.
• Room acoustics like reverberation and noise can negatively impact ASSR measurements.
• Understanding these acoustic effects is vital for clinical application.

Purpose of the Study:

• To investigate the impact of room acoustics on sound-field ASSR levels and detection rates.
• To assess the predictive capability of early decay time and a relative modulation power model for ASSR changes.

Main Methods:

• Monaural auralization used to simulate sound-field ASSR via insert earphones.
• ASSR measured in 15 normal-hearing adults using CE-Chirps® at 500-4000 Hz.
• Stimuli convolved with simulated impulse responses of three audiological testing room acoustics.

Main Results:

• Significant reduction in ASSR levels observed under room acoustic conditions compared to anechoic.
• ASSR detection rates for first harmonics remained unaffected with recordings up to 6 minutes.
• Early decay time and relative modulation power showed potential as predictors of ASSR level changes.

Conclusions:

• While room acoustics reduce ASSR levels, prolonged recording times maintain detection rates.
• Early decay time and relative modulation power are promising indicators for predicting acoustic effects on ASSR.