Many of the characteristics of ADHD involve difficulty with day-to-day tasks such as time management, organization, problem-solving, and emotional control. A region of the brain called the prefrontal cortex is especially important in regulating these skills, and it has been shown to be smaller in children with ADHD. Research has also shown other parts of the brain that regulate memory, emotion, and behavior to be smaller in children with ADHD. This could lead to some of the typical symptoms associated with the disorder. Scientists have seen differences in the way the brain functions in kids with ADHD.