Vowel quality effects on hiatus resolution in Spanish

Abstract

Hiatus Resolution refers to the various strategies that languages use in order to avoid two adjacent heterosyllabic vowels at the phonetic output. These strategies include vowel reduction, diphthongization, coalescence and deletion as the most common reported in the literature. From the point of view of production, Hiatus Resolution (henceforth HR) can be explained by the crosslinguistic preference for CV syllables. It has also been claimed that speakers apply HR strategies in a gradient manner, basing their choice of the strategy on patterns of prosodic lengthening (Simonet 2005). From a perception point of view, the avoidance of adjacent vowels is motivated by a perceptual reduction of vowel distinctions in weak contexts, which triggers changes in the vowels, in order to neutralize (or, at least, reduce) those distinctions (Fourakis 1991, Aguilar 2003, Sands 2004). Hiatus Resolution in Spanish is a phonetic phenomenon favored in contexts of reduced perceptibility, such as unstressed syllables in connected speech. The factors that affect HR are numerous and of a diverse nature: phonetic, phonological and usage-based.1 This paper explores the effects on HR in Spanish of one of these factors: vowel quality. Phonologically, Spanish sequences of non-high vowels within word boundaries are heterosyllabified, as in teatro ‘theater’ ([te. a.tro]). But when a high vowel is involved, then (i) either the high vowel bears stress and hiatus takes place, as in teoria ‘theory’ ([te.o. ri.a]) or (ii) the high vowel is unstressed and diphthongization occurs, as in peinar ‘to comb’ ([pej. nar]). Across word boundaries, vowel sequences are always heterosyllabified, regardless of vowel height or stress. However, the actual phonetic realizations of non-identical vowel sequences differ from the phonological expectations. For instance, the vowel sequence /ea/ in the word pair este asunto (‘this subject’) can be pronounced in hiatus ([es.te#a. sun.to]), with vowel reduction ([ es. te#a. sun.to]), diphthongization ([ es.tja. sun.to]) or with deletion of one vowel ([ es. ta. sun.to]). These are all strategies that Spanish uses in order to resolve hiatus sequences at the phonetic level.