Boundary- and prominence-related lengthening and their interaction.

The durational effects of prosodic boundaries and prosodic prominence are well known, but their interaction is less well-understood. Recent studies in English [Turk and Shattuck-Hufnagel (2007); Byrd and Riggs (2008)] indicate that the two effects might be interdependent. Two acoustic experiments are presented, examining the role of boundary- and prominence-related lengthening and their interaction in Greek. The first experiment explores the effects of boundary-adjacent lengthening (conditions: no boundary, intermediate phrase, intonational phrase) and prominence (on the first, second, and third syllable away from the boundary). The second experiment examines these same effects, but post-boundary. Data from eight speakers were collected. The results from five speakers are presented. Results show that pre-boundary, both prominence and boundary have an effect on segment duration. Two prosodic levels (the level of word and one higher level) are distinguished. Furthermore, for two speakers, there is an interaction effect, such that three prosodic levels are distinguished when the prominent syllable is boundary-adjacent. The post-boundary condition shows less systematic results, with different speakers exhibiting different patterns. These results suggest that prosodic effects are speaker dependent, more stable pre-boundary, and that prominence and boundaries interact, increasing prosodic boundary marking. Implications for models of prosodic structure are discussed.