Mandarin lexical tones are modified in both infant-directed speech (IDS) and Lombard
speech, resulting in tone hyperarticulation. However, it is unclear if these registers also alter
contextual tones (neutral tone and tone sandhi) and if such phonetic modification might
affect acquisition of these tones. This study therefore examined how neutral tone and tone
sandhi are realized in IDS, and how their acoustic manifestations compare with those in
Lombard speech, where the communicative needs of listeners differ. Neutral tone and tone …