Nonnative Prosody and the Intelligibility of Ambiguous Utterances

Abstract

This study examines nonnative prosody and intelligibility. Past research has suggested that prosody that is unfamiliar or inappropriate in some way can adversely affect the intelligibility of speech (e.g., Hahn, 2004; Tajima, Port & Dalby, 1997; Grover, Jamieson & Dobrovlosky, 1987; Field, 2005). In this study, the effect of overall prosody rather than the effects of particular prosodic features is analyzed. Fifteen native and 15 nonnative speakers were recorded reading identical sets of ambiguous sentences while viewing cartoon drawings. Cartoons viewed by 8 members of each speaker group portrayed one of the two possible interpretations (“Version A”) for each sentence. Cartoons seen by the remaining 7 speakers of each group showed the alternative (“Version B”) interpretations. Recordings were divided and rearranged into new soundtracks containing a different speaker for every sentence. Fifteen native listeners viewed documents showing the Version A and Version B cartoons of each sentence side by side while listening to the new soundtracks, indicating which of the two cartoon versions they believed each speaker had viewed when recording. Listeners identified the cartoon seen by the speaker significantly less often when the speaker was a nonnative, suggesting a relationship between speaker type and intelligibility. Results were further subdivided into 4 categories of structural ambiguity. Of those, compound noun vs. adjective + noun ambiguities (e.g. White House vs. white house) accounted for most of listeners’ errors in disambiguation.