Linguistics Department Colloquium:

Timo B. Roettger (Postdoctoral fellow, Department of Linguistics, Northwestern University)

Does the tune shape phonology?

Human speech has multiple information channels that can simultaneously signal different levels of meaning. One such channel consists of consonants and vowels organized into metrical structures, referred to as the text. Largely independent of these structures, there are suprasegmental modulations superimposed on the text, most notably intonation, referred to as the tune.

In contemporary theories of phonology, the text and the tune are conceived of as separate levels of phonological representation. These levels, however, exhibit a fundamental inter-dependence which is rooted in the nature of the speech transmission process. For intonation to be produced, voiced segmental material is needed to enable the vocal folds to vibrate; for intonation to be perceived, it is important for the segmental material to have periodic energy with a rich harmonic structure.

I will show that when segmental material does not allow for vocal fold modulation, or is not sufficiently sonorous to allow for optimal perceptual retrieval of pitch, languages adjust the text to provide an adequate carrier signal for intonational meaning. I will present evidence from a wide variety of languages which exhibit prosodically conditioned insertion of non-lexical vowels, suppression of otherwise regular vowel devoicing, or lengthening of existing vowels in order to accommodate the requirement to realize communicatively relevant tones.

These findings suggest that intonation poses functional pressure on its segmental hosts, leading to the temporal adjustment and preservation of existing elements or the insertion of new elements, so as to ensure the realization of intonational events. I will argue that these interactions can lead to re-occurring segmental alternations and shape grammatical morphemes.