14th International Congress of Phonetic Sciences (ICPhS-14)

San Francisco, CA, USA
August 1-7, 1999

Modelling the Growth of the Vocal Tract Vowel Spaces of Newly-Born Infants and Adults: Consequences for Ontogenesis and Phylogenesis

Louis-Jean Boë

ICP, CNRS INPG/Université Stendhal, Grenoble, France

If newly-born infants had the same sensorimotor control capabilities as adults, would their vocal tracts enable them to produce the same range of [i a u] vowel contrasts? Has increasing the volume of the pharynx by lowering the larynx been a necessary evolutionary phase for humans to produce speech? Using a new articulatory model for simulation of vocal tract growth, we calculated the shift and size of the vowel space with age. Our results show that: The maximal vowel space of newborn infants is potentially (at least) the same as adults; There is no reason to think that larynx lowering and increase in pharynx size have been guided by evolution towards speech. Our simulations allow the main flaws of Lieberman's computations to be pinpointed and invalidate his well known thesis presented in 1971 and defended even now: a low larynx and a large pharynx considered as the anatomical basis for speech.

Full Paper

Bibliographic reference.  Boë, Louis-Jean (1999): "Modelling the growth of the vocal tract vowel spaces of newly-born infants and adults: consequences for ontogenesis and phylogenesis", In ICPhS-14, 2501-2504.