English: Maturation of the brain, as reflected in the age at which a cortex area attains peak thickness, in ADHD (above) and normal development (below). Lighter areas are thinner, darker areas thicker. Light blue in the ADHD sequence corresponds to the same thickness as light purple in the normal development sequence. The darkest areas in the lower part of the brain, which are not associated with ADHD, had either already peaked in thickness by the start of the study, or, for statistical reasons, were not amenable to defining an age of peak cortex thickness. Movie of same data below. Source: NIMH Child Psychiatry Branch^[1]