Phonetics
Phonetics of ejective stops, the ejection effect, Caucasian languages, production-perception loop
While we know that the directionality of phonetic variation most likely influences observed phonological typology, it is often less clear what the primary causes of different phonetic processes are — articulatory or perceptual. For example, that vowels are phonetically longer before voiced than before voiceless stops is a well-studied phonetic generalization for which several opposing articulatory and perceptual explanations have been proposed. Most studies, however, measure vowel duration only before voiced versus voiceless stops and infer timing relations based on highly correlated parameters, which is why so many opposing explanations exist. We conducted an experiment in Georgian and Mingrelian that measured vowel durations before ejective stops while also controlling for closure and VOT duration. The results suggest that laryngeal features have an effect on preceding vowel duration and that perception is not the primary cause of durational differences in vowels. In a related experiment, we measure aspiration duration in post-aspirated stops as a function of the presence or absence of aspiration of the preceding stop (forthcoming in The Oxford Handbook of Languages of the Caucasus). The data in this experiment also suggest that a common sound change, aspiration dissimilation, is caused primarily by articulatory rather than perceptual factors.
