Lenition in Persian: A Case Study of Stop Consonants

In the present research, the lenition of stop consonants in Persian continuous speech has been investigated within the framework of laboratory phonology. Data were designed such that Persian stops were placed in three different consonantal positions, namely word initial, intervocalic word medial, and word final. Also, the stop consonants differed with respect to context (voiced vs. voiceless) as well as lexical stress (stressed vs. unstressed). Duration of stop consonants as well as their frequency of occurrence as stops, fricatives and approximants were computed. Results showed that voiceless stops resist lenition and do not lose their phonetic quality in any context. However, voiced stops show different magnitude of consonantal reduction depending on word position and context. This finding is in line with the phonetic approach to lenition, supporting the articulatory mechanisms underlying consonantal weakening, namely greater sonority, lesser articulatory effort and shortening. The results further agree with perceptual constraints underlying consonantal lenition which assume that stop consonants are more likely to be weakened inside a prosodic unit like a word rather than at its edges, also in intervocalic position, as they are surrounded with more sonorant sounds, and they are more likely to turn into approximants than fricatives.