Effects of acoustic-phonetic detail on cross-language speech production

Nonnative sounds and sequences are systematically adapted in both perception and production. For example, American English speakers often modify illegal word-initial clusters by inserting a vocalic transition between the two consonants (e.g., (/bdagu/→[b^e{schwa}dagu]). Previous work on such modifications has for the most part focused on relatively abstract properties of the nonnative structures, such as their phonemic content and whether they conform to sonority sequencing principles. The current study finds that fine-grained phonetic details of the stimulus can be equally important for predicting cross-language production patterns. Several acoustic-phonetic properties were manipulated to create stimulus variants that are phonemically identical (i.e., exhibit non-contrastive variation) in the target language (Russian). In a shadowing experiment, English speakers' correct productions and detailed error patterns were significantly modulated by the acoustic manipulations. The results highlight the role of perception in accounting for cross-language production, and establish limits on the perceptual repair of nonnative sound sequences by phonetic decoding.