Japanese 5- to 13-yr-olds who used cochlear implants (CIs) and a comparison group of normally hearing (NH) Japanese children were tested on their perception and production of speech prosody. For the perception task, they were required to judge whether semantically neutral utterances that were normalized for amplitude were spoken in a happy, sad, or angry manner. The performance of NH children was error-free. By contrast, child CI users performed well below ceiling but above chance levels on happy- and sad-sounding utterances but not on angry-sounding utterances. For the production task, children were required to imitate stereotyped Japanese utterances expressing disappointment and surprise as well as culturally typically representations of crow and cat sounds. NH 5- and 6-year-olds produced significantly poorer imitations than older hearing children, but age was unrelated to the imitation quality of child CI users. Overall, child CI user's imitations were significantly poorer than those of NH children, but they did not differ significantly from the imitations of the youngest NH group. Moreover, there was a robust correlation between the performance of child CI users on the perception and production tasks; this implies that difficulties with prosodic perception underlie their difficulties with prosodic imitation.

Child implant users enjoy music more than adult implant users. Moreover, younger age at implantation increases children's engagement with music, which may enhance their progress in other auditory domains.

Mutations in WFS1 are reported to be responsible for two conditions with distinct phenotypes; DFNA6/ 14/38 and autosomal recessive Wolfram syndrome. They differ in their associated symptoms and inheritance mode, and although their most common clinical symptom is hearing loss, it is of different types. While DNFA6/14/38 is characterized by low frequency sensorineural hearing loss (LFSNHL), in contrast, Wolfram syndrome is associated with various hearing severities ranging from normal to profound hearing loss that is dissimilar to LFSNHL (Pennings et al. 2002). To confirm whether within non-syndromic hearing loss patients WFS1 mutations are found restrictively in patients with LFSNHL and to summarize the mutation spectrum of WFS1 found in Japanese, we screened 206 Japanese autosomal dominant and 64 autosomal recessive (sporadic) non-syndromic hearing loss probands with various severities of hearing loss. We found three independent autosomal dominant families associated with two different WFS1 mutations, A716T and E864K, previously detected in families with European ancestry. Identification of the same mutations in independent families with different racial backgrounds suggests that both sites are likely to be mutational hot spots. All three families with WFS1 mutations in this study showed a similar phenotype, LFSNHL, as in previous reports. In this study, onethird (three out of nine) autosomal dominant LFSNHL families had mutations in the WFS1 gene, indicating that in non-syndromic hearing loss WFS1 is restrictively and commonly found within autosomal dominant LFSNHL families.