A case study of the speech, language and vocal skills of a set of monozygous twin girls: One twin with a cochlear implant

This case study reports on the speech, language and vocal skills of a set of monozygous twin girls; one with a pre-lingual hearing impairment and subsequent cochlear implant, the other with functionally normal hearing. The twins' skills were analysed and compared on two occasions over a seven-month period. Results from standardized assessments indicate that the speech-production and language skills of both girls were within normal limits, although analysis of their pragmatic, syntactic and discourse skills indicated that the implanted twin had some persisting difficulties. Analysis of the voice of the implanted twin indicated qualitative and quantitative abnormalities. The results suggest the need for an investigation into the voice quality of children with cochlear implants. The study also indicates the importance of early intervention and the potential benefit of early implantation and/or signing pre-implant