Profile of language abilities in a sample of adults with developmental disorders

This study investigated the profile of language abilities in a sample of high-achieving English speaking adults with developmental disorders. Ninety-seven adult participants were recruited: 49 with a dyslexia diagnosis (dyslexic group), 16 with a diagnosis of a different developmental disorder including dyspraxia, autism and SpLD (non-dyslexic developmental disorder group) and 32 with no diagnosis (non-disordered group). Dyslexic and non-dyslexic developmental disorder groups demonstrated similar impairments across measures of word reading, working memory, processing speed and oral language. Dyslexic participants showed the usual pattern of impaired phonological skills but spared non-verbal intelligence and vocabulary. There were also some suggestions of impaired structural oral language skills in this group. A data-driven clustering analysis found that diagnosis was not a reliable predictor of similarity between cases, with diagnostic categories split between data-driven clusters. Overall, the findings indicate that high-achieving adults with developmental disorders do demonstrate impairments that are likely to affect success in higher education, but that support needs should be assessed on a case-by-case basis, rather than according to diagnostic label.