Lexically-based Vowel Dispersion: a Case Study for Dutch1

The 'vowel dispersion theory' states that the acoustic structure of the vowel inventory in a language can be explained by optimizing the acoustic inter-vowel contrast, under the constraint of articulatory conditions. In this paper, the primacy of the acoustic principles of contrast and effort is questioned by considering the possible effect of the lexicon on vowel dispersion. As an extreme point of view, the need for acoustic contrast between two vowels will be assumed to be determined only by the 'functional load' of the vowel opposition. This functional load is determined by the lexicon. The results for Dutch indicate that the functional load explains at least a part of the acoustic structure of the Dutch vowel inventory. Since the model is tested for one language only, we emphasize the used methodology, rather than the language-specific results.