With National Science Foundation support, under the direction of Dr. Ellen Broselow, Ms. Marianne Boroff will conduct fieldwork in southeastern Mexico on syllable structure in Yatzachi Zapotec (YZ) for her doctoral dissertation. Syllables have long been considered a fundamental unit in speech; they organize speech sounds into larger units, which are themselves organized into words. Explanations of such phenomena as stress assignment patterns and regular sound alternations (allophony) depend crucially on the notion of syllable. More importantly, speakers with no prior linguistic knowledge show themselves to be aware of the syllable structure of their language; they can count syllables when asked, and overtly make use of this knowledge in accomplishing certain tasks, for example in enunciating a word or in some language games. Where does the information upon which this knowledge is based come from? Phoneticians have found it difficult to pin down the exact properties of the speech stream that allow us to determine syllable structure; syllable structure is impossible to read off of the acoustic output of an utterance. Therefore, syllables must be considered abstract units of mental representation rather than physical objects in the speech stream.
This dissertation research contributes to the understanding of the notion of the syllable by examining the patterning of consonants and vowels with respect to syllable structure. Cross-linguistically, there is a preference for syllables that begin in a consonant over syllables that begin in a vowel; every language allows CV syllables, and some languages require an initial consonant. Can we attribute the preference for vowels to have preceding consonants to factors other than syllable structure? In YZ, vowel sequences are not allowed, a fact that would traditionally be explained by the fact that the second vowel belongs to a syllable that doesn't start with a consonant. However, YZ also does not allow vowels separated by a glottal stop (the intervocalic sound found in the English word uh-oh), even though glottal stop is a consonant in the language, and therefore should in principle fulfill the requirement that all syllables begin with a consonant. Clearly, something else is at work here that results in the failure of both vowel sequences and vowel sequences separated by a glottal stop - something other than syllable structure alone. Furthermore, many languages treat glottal stops differently from other consonants, allowing vowels to spread across them or requiring that the vowels on either side of the glottal stop be identical, and various languages restrict glottal stop to particular positions. In this study, we attempt to answer these questions: Why must vowels be preceded by a consonant in the first place? Is there anything special about vowels that make vowel sequences disfavored (as opposed to single vowels in initial position)? Is there any particular property of a glottal stop that explains why it should not be permitted to begin a syllable in some languages? Why should there be a preference for vowels flanking glottal stop to be identical? This study will not only help to explain the YZ data, but will also contribute to the debate concerning the relative contributions of abstract units of organization such as the syllable vs. constraints on the timing of physical vocal tract gestures in organizing speech.
