Time course of a perceptual enhancement effect for noise-masked speech in reverberant environments

Speech intelligibility has been shown to improve with prior exposure to a reverberant room environment [Brandewie and Zahorik (2010). J. Acoust. Soc. Am. 128, 291-299] with a spatially separated noise masker. Here, this speech enhancement effect was examined in multiple room environments using carrier phrases of varying lengths in order to control the amount of exposure. Speech intelligibility enhancement of between 5% and 18% was observed with as little as 850 ms of exposure, although the effect's time course varied considerably with reverberation and signal-to-noise ratio. In agreement with previous work, greater speech enhancement was found for reverberant environments compared to anechoic space.