Syllabic structure and informational content in English and Spanish

This paper investigates the potential role of syllabic structure in characterising the informational content of running speech using an energy-based measure (the cochlea-scaled entropy, CSE index). We computed the CSE and compared how it aligned to the energy envelope for a corpus of English and Spanish sentences. We also compared these measures to syllabic structure, which differs markedly between the two languages. Results show that English exhibits a clear difference between informational and energy peaks in relation to the phonetic syllable nucleus, defined here in terms of the temporal mid-point of adjacent vowels. In contrast, in Spanish, both peaks align. Further, energy peaks occur later in the syllable in English, whereas they precede the nucleus in Spanish. Evaluation of internal syllable timing showed a more regular timing pattern in Spanish than English, which we suggest could have an implication for automatic selection of information bearing elements of speech.