Prosodic grouping in Papuan Malay, Akan and German

Grouping is an important function of prosody because it helps listeners to break down the speech signal into smaller units. Specific acoustic cues, in particular duration and intensity, have been reported to determine how disyllabic units (i.e., feet) are grouped across languages (Iambic-Trochaic Law - ITL). However, previous work has shown that speakers of different languages vary in the extent to which they use the ITL. It has been proposed that the linguistic modulation of the ITL relates to cross-linguistic differences in word and phrase prosody. The present study further investigates the predictions of the ITL in two under-researched languages, Papuan Malay and Akan, which have been reported to have no or highly regular word stress. They are compared to German, a well-researched language with variable word stress. A perceptual grouping task used in previous work is replicated with listeners from each language. The results show considerable cross-linguistic differences between the languages and are interpreted in line with the (word) prosodic properties of Papuan Malay and Akan. The outcomes reconfirm cross-linguistic variability and modulation of the limited applicability of the ITL across languages, and they provide insights into the word-prosodic structure (e.g., word stress, tone) of the respective languages.