Objective: The present study aims to explore the neuropsychological features of children with Attention-Deficit/Hyperactivity Disorder (ADHD) and Sluggish Cognitive Tempo (SCT).
Methods: Fifty-eight children with ADHD+SCT, 480 children with ADHD-SCT, and 105 healthy controls (HC) were recruited. Neuropsychological tests and the Behavior Rating Inventory of Executive Function (BRIEF) were used.
Results: The ADHD+SCT group performed worse than the HC in processing speed (p = .005), set-shifting (p = .0003), interference control (p = .00014), and visual memory (p = .007), while the ADHD-SCT group performed worse than the HC in sustained attention measurements (all p < .0001). The ADHD+SCT group scored higher than the ADHD-SCT group in the following factors from BRIEF: plan/organize (p = .00083), working memory (p < .001), and shift (p = .0054).
Conclusion: Our results indicated that SCT symptoms are associated with worse executive function in children with ADHD except for sustained attention.
Keywords: ADHD; cognitive functioning; sluggish cognitive tempo.