Little is known about executive function among adolescents with a childhood diagnosis of attention-deficit/hyperactivity disorder (ADHD), and there is a lack of such information in an ethnic Chinese population. This study investigated nonverbal executive functions in adolescence among Taiwanese children with ADHD.
The sample included fifty-three 11- to 16-year-old adolescents (male, 75.5%) with a childhood diagnosis of ADHD according to the DSM-IV criteria, and 53 age-, sex-, IQ-, and parental education-matched comparison adolescents. They were assessed using psychiatric interviews (mothers included), the Weschler Intelligence Scale for Children-3rd edition, and the tasks involving the executive functions of the Cambridge neuropsychological test automated battery: the spatial span, spatial working memory, intradimensional/extradimensional shifts, and stocking of Cambridge. A linear multilevel model was used for data analysis for the matched case-control study design and repeated measures within the same participants.
Forty-three adolescents (81.1%) had persistent DSM-IV ADHD diagnosis. The ADHD group made more errors in the spatial span and spatial working memory, had more complete stage trials in the intradimensional/extradimensional shifts, and had fewer problems solved and shorter initial and subsequent thinking time in the stockings of Cambridge than the controls. The magnitudes of group differences increased with increased task difficulties. Persistent ADHD and methylphenidate did not make significant difference in executive functions.
The findings of the authors suggest that adolescents with childhood ADHD need extra assistance when they are assigned complex tasks regardless of persistence of ADHD at adolescence.