Inhibitory Control, Conduct Problems, and Callous Unemotional Traits in Children with ADHD and Typically Developing Children.

Compared children with CP/ADHD, CPCU/ADHD, ADHD-only, and controls on two measures of inhibitory control: a Simon/flanker task that measured response selection and a stop signal task that measured response inhibition. Results showed: (a) ADHD was associated with both measures of inhibitory control; (b) control children had better overall performance and ADHD-only had worse response selection than the CP groups; and (c) children with CPCU/ADHD had better response inhibition than children with ADHD-only or CP/ADHD. Results suggest inhibitory control dysfunction is associated with ADHD rather than CP and that response inhibition dysfunction distinguishes children with CP/ADHD from children with CPCU/ADHD.