* Clinical and Neuropsychological Characteristics of ADHD According to DSM-5 Age-of-Onset Criterion in Korean Children and Adolescents.
- Objective: The aim of this study was to compare the clinical features and neuropsychological profiles of children and adolescents with ADHD according to the age-of-onset defined in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5). Method: We compared the following three groups: early-onset ADHD group (onset before age 7, n = 86), late-onset ADHD group (onset between ages 7 and 12, n = 58), and the control group (n = 88). Results: Both early-onset and late-onset ADHD groups had more symptoms and functional impairments than the control group. Also, both ADHD groups scored higher on ADHD Rating Scale, Parent General Behavior Inventory, majority of the subscales of Social Responsiveness Scale, Hyperactivity subscale of Korean Personality Rating Scale for Children, and Omission Errors of Visual Continuous Performance Test compared with the control group. Conclusion: Our results support the extension of age-of-onset criterion made in DSM-5.
* Auditory and Visual Executive Functions in Children and Response to Methylphenidate: A Randomized Controlled Trial.
- Objectives: The aim of the study was to assess auditory and visually based executive functions (EFs) and the effect of methylphenidate (MPH) in children with ADHD. Methods: Thirty-six boys between the ages of 8.3 and 9.7 years with ADHD and 36 matched controls were included. The study group was randomized into MPH and placebo for 7 days each in a crossover design. A Cued Choice Reaction Time (CCRT) test that included incongruent cuing was administered at baseline and following 1 and 2 weeks. Results: The difference between the study and control groups was more evident with visual cues and incongruent cuing. Increased gains by children with predominantly hyperactive-impulsive\combined (HI\C) type of ADHD were observed under MPH. Conclusions: The differences between children with ADHD and typical children are more pronounce under incongruent auditory cuing . The gains attributable to MPH are more specific to tasks involving auditory and visual EFs and in children with HI\C type ADHDs.