Communication development in young deaf children: review of the video analysis method.

It is widely recognised that preverbal communication skills underpin development of spoken language. This historical review outlines the establishment of a quantitative methodology for assessing preverbal communication skills in children with hearing aids and cochlear implants. The method is shown to be reliable and free from observer bias. The review also summarises findings from a series of cross-sectional and longitudinal observational studies utilising the methodology. Profoundly deaf young children, either with cochlear implants or successful users of hearing aids, show similar patterns of preverbal communication development that contrast with those of unsuccessful hearing-aid users. Preverbal measures obtained 12 months after implantation are predictive of late performance on speech perception tasks. Moreover, there is a significant association between the preverbal measure of 'autonomy' obtained before implantation and later speech perception performance. This latter finding has important theoretical implications for understanding of language development and suggests that intervention that promotes autonomy in adult-child interaction may lead to improved outcomes. Such intervention could be commenced as soon as deafness is discovered.