Disorders of language development, with particular reference to central deafness.

Many disorders may result in delay of language development. There is on the one hand a large group of children with bilateral peripheral deafness, most of whom will be amenable to appropriate treatment, and on the other a group, possibly more numerous, who have a variety of disorders of speech and language, varying from lack of speech associated with severe mental retardation to more specific defects, such as congenital dyslexia and developmental articulatory dyspraxia. These disorders are probably due to a defect of cerebral function at the highest level and in these children no-one will have suspected deafness or have suggested that there is an abnormal response to auditory stimuli. Some children will start life with such an abnormal response but as they grow older will cease to show the characteristics of deafness. This group is analysed and it is suggested that some may be diagnosed as suffering from central deafness. The E. E. G./Audiogram is useful in the differenciation of these children from those with perpheral deafness, especially at an early age when co-operation is limited, or when these are severe emotional disturbances or infantile psychoses. This technique will be briefly discusses. Children with central deafness may be included among those with disorders of language development, but it is possible that this disability may sometimes result from a failure of integration at a cortical level. The reason for suggesting this diagnostic category is to stress that these children do initially behave in a similar way to those who are perpherally deaf.(ABSTRACT TRUNCATED AT 250 WORDS)