COGNITIVE NEUROPSYCHOLOGY AND DEVELOPMENTAL DISORDERS - UNCOMFORTABLEBEDFELLOWS

Cognitive neuropsychology provides a theoretical framework and methods that can be of value in the study of developmental disorders, but the ''dissociation'' logic at the centre of this approach is not well sui ted to the developmental context. This is illustrated with examples fr om specific language impairment. Within the developing language system there is ample evidence for interaction between levels of representat ion, with modularity emerging in the course of development. This means that one typically is seeking to explain a complex pattern of associa ted impairments, rather than highly selective deficits. For instance, a selective impairment in auditory processing can have repercussions t hrough the language system and may lead to distinctive syntactic defic its that are seen in written as well as spoken language. Changes in th e nature of representations and in the relationships between component s of a developing system mean that cross-sectional data at a single po int in development may be misleading indicators of the primary deficit . Furthermore, traditional cognitive neuropsychology places a dispropo rtionate emphasis on representational (competence) deficits, with proc essing (performance) deficits being relatively neglected. Methods for distinguishing these two kinds of impairment are discussed, as well as other approaches for elucidating the underlying nature of development al disorders.