High sentence predictability increases the fluctuating masker benefit.

Area of Science:

• Auditory perception
• Speech processing in noise
• Psychoacoustics

Background:

• Understanding speech in noisy environments is crucial for communication.
• Fluctuating maskers, unlike steady-state ones, offer brief moments of silence (glimpses) that can aid speech perception.
• The benefit derived from these glimpses, known as fluctuating masker benefit (FMB), is influenced by various acoustic and linguistic factors.

Purpose of the Study:

• To investigate how sentence predictability and masker modulation type affect the fluctuating masker benefit (FMB).
• To determine if sentence predictability interacts with masker characteristics to influence speech reception thresholds.

Main Methods:

• Speech reception thresholds were measured using sentences with varying predictability levels (high vs. low).
• Two types of amplitude modulations were imposed on a steady-state masker: square-wave and sinusoidal.
• The fluctuating masker benefit (FMB) was calculated as the difference in speech reception thresholds between fluctuating and steady-state maskers.

Main Results:

• Square-wave modulations yielded a significantly larger FMB compared to sinusoidal modulations.
• Sentences with high predictability resulted in greater FMBs than those with low predictability.
• The positive effect of sentence predictability on intelligibility was more pronounced with fluctuating maskers than with steady-state maskers.

Conclusions:

• Both masker modulation type and sentence predictability are critical factors influencing speech intelligibility in fluctuating noise.
• Higher sentence predictability enhances the utility of speech envelope glimpses within masker dips.
• The findings highlight the complex interplay between acoustic masker properties and linguistic context in auditory perception.