The influence of accentuation and polysyllabicity on compensatory shortening in German

The aim of this study was to investigate the relationship between compensatory shortening and coarticulation in German tense and lax vowels in trochees and iambs and to determine whether this relationship was influenced by prosodic accentuation. Speakers produced near minimal pairs differing in vowel tensity in monosyllabic and disyllabic words (both trochees and iambs) in accented and deaccented contexts. We found significant effects of polysyllabic shortening, but only in tense vowels of nuclear-accented target words. Both stress patterns (trochaic and iambic) showed equal effects of polysyllabic shortening. Thus, while the duration of tense vowels in this study depended on accentuation and syllabicity, perhaps in order to provide perceptual cues for the listener, lax vowels were immune from lengthening and shortening phenomena. As a result, the durational difference between tense and lax vowels appears to lessen in prosodically weak contexts. The greater overlap of acoustic duration in deaccented contexts may contribute to the origin of the diachronic merger of tense and lax vowels in some languages.