The importance of prosody for TRP projection

TitleThe importance of prosody for TRP projection
Publication TypePresentation
Year of Publication2007
Conference NameSummer Meeting on Prosody
AuthorsWesseling, Wieneke
PublisherNederlandse Vereniging voor Fonetische Wetenschappen
Conference LocationNijmegen, The Netherlands
Abstract

In three different Reaction Times (RT) experiments, the effect of various prosodic features - like end tone, position of prominent words and utterance length - on the projection of potential turn changes, also known as Turn Relevance Places (TRPs) was investigated. Subjects were asked to react with minimal responses to prerecorded dialogs and impoverished versions of these dialogs.

The first two experiments - with both full and impoverished versions of the dialogs, containing only intonation and pause information (hummed stimuli), or no periodic component at all (whispered stimuli) - already showed that end tone information can be used by listeners to predict upcoming utterance ends, although in natural speech the pitch signal itself might be redundant for predicting TRPs.

It also seemed that the presence of non prominent words right before an utterance end reduced the delays of both elicited and natural responses. This would suggest that the presence of a prominent, informative, word starts the projection of a possible upcoming TRP, while the availability of non prominent, predictable, speech then allows listeners to improve their predictions of the exact timing of the TRP.

However, in a third experiment, where at random, of each utterance, either one of the last four words was replaced by white noise (masked condition), or no word was replaced (non masked condition), the masking of prominent words did not affect the response times of our subjects. Only when it was the very last word of the utterance that was masked, the reaction time was delayed. It seems that effect of prominent word position that was found earlier, is in fact an effect of utterance length.

Our results suggest that predicting the relative position of the last word before the TRP is robust enough to be unaffected by missing either intonation, or individual words. The strong facilitating effect of utterance length on RTs also points to the use of global syntactic and discourse structure in predicting the relative position of the last word.