The phonetic space of phonological categories in heritage speakers of Mandarin
In two experiments, we investigated the production of Mandarin and English by heritage speakers of Mandarin in comparison to native Mandarin speakers and late learners. In Experiment 1, speakers in all groups made an F2 distinction between Mandarin and English back vowels, with native Mandarin speakers' vowels in both languages having lower F2 values than those of heritage speakers and late learners. In addition, heritage speakers were found to achieve the greatest separation between similar vowel categories. In Experiment 2, few speakers made a VOT distinction between Mandarin unaspirated and English voiced; however, native Mandarin speakers and heritage speakers did distinguish Mandarin aspirated and English voiceless, both groups putting more distance between the two categories than late learners. Thus, we found that heritage speakers maintain not only language-internal contrasts, but also cross-linguistic contrasts, a result which likely stems from an acute approximation of phonetic norms that occurs during early exposure to both languages.