Music and speech share many acoustic commonalities and cognitive mechanisms. Previous studies have found that music training can improve categorical perception (CP) of Mandarin tones in adult musicians. However, it remains to be established whether music training can enhance the categorical perception of Mandarin tones in young children and whether the training effects can be influenced by the training duration.

The present study used a 2 (group: music training vs no-training) × 3 (test time: pre vs 6-month post vs 12-month post) between-and-within-subjects design to investigate the effects of music training on 4- to 5-year-old children’s CP of a Mandarin lexical tone continuum (from Tone 1 to Tone 2). The music training consisted of 110 sessions, 30 minutes per session, and three sessions per week for 12 months involving 20 preschoolers. The children were assigned to two groups, music training group (n = 20, age range from 49.69 months to 51.42 months, SD = 2.91 months) and control group (n = 20, age range from 51.69 to 52.56 months, SD = 3.0 months). In the music training group, the instructor guided children in activities leading to playing the small carillon, while children in the no-training group were given routine class activities. Each session of music training consisted four parts: Part 1 was “listen and sing songs” in which children learned to master notes and focus attention on subtle pitch changes; Part 2 was “listen and discriminate musical notes”, children learned to play a single note accurately according to the background music; Part 3 was “listen and play the carillon”, children listened to pitch changes in the background music, sang the notes and played the whole song melody; Part 4 was “play the carillon along with actions”, children listened to the background music and learned to play the carillon along with simple dancing actions. Children’s CP of tone continuum was measured before the learning began, after 6- month and after 12- month training using two tasks (identification test and discrimination test).

This study investigated if music training can enhance children’s boundary position, boundary width, within-category and between-category discrimination accuracy in CP of Mandarin Tone 1 and Tone 2 through 2 (group: music training vs no-training) ×3 (test time: pre vs 6-month post vs 12-month post) repeated measures ANOVA. The results revealed that although the perceptual boundary positions and ability to discriminate between-category tone pairs were unaffected by training, the boundary width values and within-category discrimination accuracies differed significantly between the experimental and control groups. The analysis of boundary width values and within-category discrimination accuracy revealed a significant interaction between group and test time. An analysis of simple effects further indicated that in the pretest and 6-month posttest, there was no significant effect between music training group and no-training group. In the 12-month posttest, the boundary width decreased significantly and the within-category discrimination accuracies increased significantly in the music training group, while no significant differences were found on boundary width and within-category discrimination accuracy in the control group. These results suggest that long-term music training can enhance children’s CP of Mandarin tonal contrasts.

In conclusion, our results supported the OPERA theory that music training can raise the steepness of boundary widths and enhance children’s sensitivity to subtle pitch differences between within-category sounds in the presence of robust mental representation in the service of CP of lexical tonal contrasts.

Keywords： music training ; cross-domain transfer ; categorical perception of tonal contrast ; 4- to 5-year-old children