|
|
Attention-Deficit/Hyperactivity Disorder (ADHD) applies to a behavioral profile of difficulties that include developmentally inappropriate levels of inattention, hyperactivity, and impulsivity and is one of the most commonly diagnosed pediatric conditions worldwide. In therapeutic settings, ADHD frequently co-occurs with other behavioral and neurodevelopmental disorders, including language impairment (LI). This has encouraged consideration of the possibility that ADHD and LI might be etiologically linked. In this talk, I will review the mixture of supports and challenges that characterizes the current evidence base on this issue. I will suggest that a large portion of the cross-signals can be resolved when the clinical metrics that have been used to assign LI and ADHD statuses are partitioned. Measures of verbal memory and morphosyntactic proficiency appear to be well-suited to the task of differentiating LI from ADHD whereas measures of vocabulary, verbal IQ, and pragmatic competence appear to be poorer options. Similarly, parental ratings of hyperactivity and impulsivity symptoms have been better at segregating ADHD from LI than ratings of inattention, ratings from teachers, indices from continuous performance tests, or executive function measures. I will present new evidence from cases of co-occurring ADHD+LI which suggest that the presence of ADHD within the profiles of children with LI does not contribute to the severity of their language impairments. Different models of LI, ADHD, and Reading Disability linkages will be considered as well. I will conclude with the suggestion that moving forward, study samples of ADHD will provide a better comparison group for testing key assumptions of emerging models of language impairment (e.g. information processing deficits, implicit learning/procedural memory deficits) than groups of typical developing children. This research has been funded by grants from the National Institute on Deafness and Other Communication Disorders (R03DC008382; R01DC011023). |
|