Exploring phonetic predictors of intelligibility, comprehensibility, and foreign accent in L2 Spanish speech

Although current approaches to second language (L2) pronunciation underscore that instruction should concentrate on pronunciation features that help learners be more intelligible (and not necessarily more native like), there is little empirical evidence as to what those features are, especially in languages other than English. To address this gap, this exploratory study examined phonetic predictors of listener-based dimensions-namely, intelligibility, comprehensibility, and foreign accent-in L2 Spanish speech. Samples were taken from 42 Spanish learners of varying proficiency while performing a picture description task, rated for global measures by 80 native Spanish listeners, coded for phonemic errors, and analyzed phonetically for pronunciation features that previous research has reported as challenging for English-speaking learners. Mixed-effects models were fit to the data to examine relationships between the phonetic features and the listener-based dimensions. Results revealed that rising intonation and diphthongization of word-final /o/ predicted intelligibility, rising intonation predicted comprehensibility, and a variety of features were associated with foreign accent. Overall, results confirmed that non-target-like production of L2 pronunciation, including areas known to be challenging for Spanish learners, does not necessarily lead to intelligibility and comprehensibility issues. Based on these findings, we make recommendations regarding what features should be prioritized in L2 pronunciation instruction.