Supplementary Material for: Stability and Variability in Slovak Prosodic Boundaries

Background/Aim: Encoding intended meanings in the type and strength of prosodic boundaries and strategies for communicating these meanings in ambient noise use similar prosodic cues. We analyze how increasing the level of ambient noise affects the realization of Slovak prosodic boundaries. Methods: Five native speakers of Slovak read sentences, manipulating the boundary type (weak, rise, fall) and the location of pre-boundary pitch accent. Ambient noise of several levels was administered via headphones. Acoustic and articulatory data (electromagnetometry) were collected. Results: Under normal condition, boundary strength is signaled with longer pre-boundary rhymes, more frequent pauses, greater crossboundary f0 resets and jaw displacement. The strength of falls is realized in crossboundary features (pauses, f0 reset), and rises in pre-boundary features (rhyme duration, f0 range). Pitch-accented rhymes are strengthened in all features, but f0 range. In noise, the increase in boundary strength is weak, and falls strengthen more than rises. F0 targets for falls and rises are adjusted in addition to noiseinduced global f0 scaling and lengthening. Conclusion: Hyper-articulation of prosodic boundaries in ambient noise is not robust and uniform; rather, durational, f0 and jaw displacement features co-create complex prosodic patterns in a complementary and synergetic manner based on affordances in normal speech.