Production training in second language acquisition: a comparison between objective measures and subjective judgments

This paper reports on an exploratory study of the processes involved in the acquisition of new phonetic control regimes in L2 learning. We focus here on the acquisition of long VOT initial stops by French native speakers undergoing production training. Francophone speakers were asked to repeat /ta/ stimuli varying in VOT and burst intensity. The performances in production are assessed through a comparison between objective measures performed on the speech signals (VOT, burst intensity) and subjective measures from L2 listeners themselves (in terms of similarity between the model and the response) and from American English native listeners (in terms of similarity as well as L1 typicality). Results show that (i) the Francophone speakers reasonably matched in their responses the VOT and burst intensity variations of the stimuli; (ii) that the three subjective indices are highly correlated with each other, but that they only partially correlate with the acoustic parameters measured on the signals; (iii) that inter-individual variation is very large, among the speakers’productions as well as among the listeners’judgments.