Just-noticeable differences of fundamental frequency change in Mandarin-speaking children with cochlear implants.

Abstract

Fundamental frequency (F0) provides the primary acoustic cue for lexical tone perception in tonal languages but is poorly presented in cochlear implants (CIs). Currently, there is still a lack of understanding on the sensitivity to F0 information in CI users speaking tonal languages. In the present study, just-noticeable differences (JNDs) of F0 contour and F0 level change in Mandarin-speaking kindergarten-aged children with CIs were measured and compared with those in age-matched normal-hearing (NH) peers. Statistical analysis showed that both JND of F0 contour change (JND-C) and JND of F0 level change (JND-L) were significantly larger in CI group than in NH group. Furthermore, within-group comparison of JND-C and JND-L found that JND-C was significantly smaller than JND-L among children with CIs; however, opposite pattern was observed among children with normal hearing. The contrary sensitivity to F0 contour and F0 level change between children with CIs and children with normal hearing suggest discrepant mechanisms of F0 processing in these two groups as a result of hearing experience.