A Comparative Study of Native Speakers of Japanese and Italian Learners of Japanese as a Second Language: Acoustic Realizations of Rendaku Voicing in Compounds

<p>In this study we explore the acquisition of rendaku voicing by learners of Japanese whose first language is Italian, drawing upon acoustic measurements of the duration of alveolar fricatives. It is well-attested that, in Italian, the alveolar fricative /s/ turns into its voiced counterpart /z/ when followed by a sonorant at a word boundary. The present study, assuming the speech model proposed by Levelt (1989), examines recordings of the learners’ utterances to see how the Italian learners’ word-internal intervocalic-s voicing affects their formation and processing of compounds in Japanese from the viewpoint of rendaku. Specifically, we focus on items containing an alveolar fricative in a word-internal position and the acoustic duration of the phonetically realized target segments. The experiment, involving seven Italian learners of Japanese (L2 participants) and six native speakers of Japanese (L1 participants), elicited sets of compounds consisting of two nouns, of which the second element began with an alveolar fricative. The two participant groups showed no significant differences in average duration and the voiced segments were shorter than the voiceless segments that underwent rendaku. The acoustic realizations of the voiced alveolar fricative /z/ in the data from the L2 participants showed a tendency similar to that of the L1 Japanese participants, but the L2 participants displayed greater individual variability than the L1 participants. Given these results, we surmise that the resources available for the learner to use the Lexicon to process information on the path from the Formulator to the Articulator, as well as to activate the muscles of the speech organs, vary and develop in accordance with level of language acquisition. </p>