Metaphony in the tricase Southern Salentino variety: acoustic, articulatory, and phonological analysis

Southern Salentino varieties have a five-vowel system, /i, ɛ, a, ɔ, u/, exhibiting harmonic alternations in stressed mid-vowels: /ɛ/ and /ɔ/ raise to the mid-close [e] and [o], respectively, when followed by high vowels [i] and [u]. This harmony process is traditionally referred to as metaphony. Southern Salentino metaphony is characterized by variation in the way in which the unstressed [i] and [u] affect the stressed vowels /ɛ/ and /ɔ/. We examined the Southern Salentino dialect spoken in Tricase, focusing on both interspeaker and intra-speaker variation. Our primary goal is to understand the acoustic and articulatory characteristics of the metaphonic patterns and identify the features involved in this assimilatory process. Acoustically, we found that the metaphonic variant [e] has lower F1 and higher F2 values than /ɛ/, and the variant [o] exhibits lower F1 and F2 values than /ɔ/. We also show that the articulatory feature [±ATR] is significantly correlated with the metaphonic contrasts. Our second goal is to develop an appropriate phonological analysis of the phenomenon and describe the interacting parameters that generate the observed metaphonic variation. We argue that a key factor in the variation is the constraint against [+back, +ATR] vowels, which prevents high [+back, +ATR] triggers and/or mid [+back, +ATR] outcomes. After ruling out sociolinguistic factors, we propose that, although phonologized, the metaphonic process is still not fully normative in the community’s speech, leading to both interspeaker and intra-speaker variation.