Speech, Vocabulary, and the Education of Children Using Cochlear Implants
Authors: Connor Carol McDonald , Hieber Sara , Arts H. Alexander , Zwolan Teresa A. 
Published: July 2014

This study examines the relationship between the teaching method, oral or total communication, used at children's schools and children's consonant-production accuracy and vocabulary development over time. Children who participated in the study (N=147) demonstrated profound sensorineural hearing loss and had used cochlear implants for between 6 months and 10 years. Educational programs that used an oral communication (OC) approach focused on the development of spoken language, whereas educational programs that used a total communication (TC) approach focused on the development of language using both signed and spoken language. Using Hierarchical Linear Modeling (HLM) we compared the consonant-production accuracy, receptive spoken vocabulary, and expressive spoken and/or signed vocabulary skills, over time, of children who were enrolled in schools that used either OC or TC approaches, while controlling for a number of variables. These variables included age at implantation, preoperative aided speech detection thresholds, type of cochlear implant device used, and whether a complete or incomplete active electrode array was implanted. The results of this study indicated that as they used their implants the children demonstrated improved consonant-production accuracy and expressive and receptive vocabulary over time, regardless of whether their school employed a TC or OC teaching method. Furthermore, there appeared to be a complex relationship among children's performance with the cochlear implant, age at implantation, and communication/teaching strategy employed by the school. Controlling for all variables, children in OC programs demonstrated, on average, superior consonant-production accuracy, with significantly greater rates of improvement in consonant-production accuracy scores over time compared to children in TC programs. However, there was no significant difference between OC and TC groups in performance or rate of growth in consonant-production accuracy when children received their implants before the age of 5 years. There was no significant difference between the OC and TC groups in receptive spoken vocabulary scores or in rate of improvement over time. However, children in the TC group achieved significantly higher receptive spoken vocabulary scores than children in the OC group if they received their implant before the age of 5 years. The TC group demonstrated superior scores and rates of growth on the expressive vocabulary measure (spoken and/or signed) when compared to the OC group if they received their implants during their preschool or early elementary school years. There was no significant difference if the children received their implants during middle elementary school. Regardless of whether children were in the OC or TC group, children who received their implants during preschool demonstrated stronger performance, on average, on all measures over time than children who received their implants during their elementary school years. The results of this study suggest that children may benefit from using cochlear implants regardless of the communication strategy/teaching approach employed by their school program and that other considerations, such as the age at which children receive implants, are more important. Implications and future research needs are discussed.