Spatio-temporal integration of speech reflections in listeners with sensorineural hearing loss
* Presenting author
Abstract:
For speech intelligibility in rooms early reflections are typically assumed to be beneficial for speech intelligibility while late reflections are considered to be detrimental. This concept was challenged in a recent study employing binaural room impulse responses (RIRs) with systematically varied interaural phase differences (IPDs) of the direct sound and a variable number of reflections delayed by up to 200 ms. Speech recognition thresholds (SRTs) in stationary noise measured in normal-hearing listeners showed that, when IPD favored late RIR components, listeners appeared to be capable of focusing on these components rather than on the precedent direct sound, which is at odds with common room acoustical measures. This contribution extends these results to listeners with sensorineural hearing loss. Stimuli were individually amplified by a linear prescription rule to minimize the influence of audibility. The data indicated that all listeners had (close-to-)normal SRTs in the reflection-free diotic reference condition (S0N0) and at least a residual binaural benefit in SπN0 condition. However, in conditions including one or more late reflections, most listeners struggled heavily, suggesting that spatio-temporal integration of speech information represents a significant challenge even for listeners with normal aided performance in simpler speech recognition tasks.