Polish iterative stress and its phonetic parameters in quiet vs. noisy environments

Abstract

Research on English has shown that the phonetic contrast between stressed and unstressed syllables is enhanced in speech produced in the presence of background noise. In this study, we test whether the so-called Lombard effect is mediated by prosodic structure also in a language with predictable stress. We investigate the effect of noisy environment on the production of rhythmic stress in Polish, which is a well-documented iterative stress system. Our findings demonstrate that background noise has a differential effect on the parameters reflecting entirely predictable and thus phonologically redundant rhythmic structure; however, the interaction between stress and noise is not uniform across the acoustic parameters (consonantal/vocalic duration, fundamental frequency, intensity), rhythmic stress position (word-initial vs. word-medial) and the type of noise (white noise vs. multi-talker babble). Also, the effect is that of preservation or loss rather than enhancement of the parameters in question. The enhancement vs. selective preservation of acoustic differences between stressed and unstressed syllables in English and Polish depends, among other things, on the degree of redundancy (or functional relevance) of the linguistic structure that these parameters express.