Cognitive characteristics of intellectually gifted children with a diagnosis of ADHD

Some children may be intellectually gifted, and yet experience behavioral and academic difficulties. We examined 82 twice exceptional children (2e-ADHD), having an excellent General Ability Index (GAI) derived from the Wechsler Intelligence Scale for Children-IV (GAI >= 125), and a diagnosis of Attention Deficit and Hyperactivity Disorder (ADHD). They accounted for 8.8% of a large sample of children with ADHD, which is twice as high as the proportion of intellectually gifted children in a typical population. This over-representation does not reflect a misdiagnosis of ADHD, as these children showed the typical features predicted on the grounds of data regarding the ADHD sample, including lower scores in working memory and processing speed measures, combined with the inclusion criteria for giftedness. Based on information concerning intellectually gifted children with either a Specific Learning Disorder (SLD) or typical development, we observed that these characteristics of intelligence are similar to those seen in SLD, but not in typical development, irrespective of whether 2eADHD children had a comorbid SLD.