Categorical Perception of Lexical Tone in 6 to 8-year-old Monolingual and Bilingual Children

Given that Mandarin is a tone language and English is not, the present study investigated the perception of Mandarin tones in young school-aged children with or without tone language exposure. Mandarin Monolingual (MM), English-Mandarin Bilingual (EMB) and English Monolingual (EM) children aged 6 to 8 years participated in tone identification and discrimination tasks. Tone identification and discrimination scores of manipulated Tone 1-Tone 2 and Tone 1-Tone 4 fundamental frequency continuum were measured. MM and EMB children exhibited categorical boundaries in tone identification, but EM children did not. MM children showed steeper identification slopes than EMB children. Tone discrimination showed modest peaks across tone categories for the MM and EMB children, but did not present peaks for the EM children, possibly due to underdeveloped capacity to discriminate tonal glides for children. Performance differences across the three groups could be possibly attributed to children’s varied language backgrounds. Tone language exposure seemed critical for children to perceive lexical-level tonal changes.