ADHD involves inattention, impulsivity, and hyperactivity, whereas autism is characterized by stereotyped behavior and impaired social and communication skills. On the surface, there seems to be little in common between these two disorders at first glance.
One feature they do have in common is that they rarely present alone. In the words of two researchers:[1] “It is the exception, not the rule, to encounter cases with ‘pure’ ADHD”, and the same also seems to hold true for ASD. It’s not uncommon for attention issues and full-blown ADHD to be found[2] in children with ASD. The reason aspects of these conditions can overlap may come down to where they occur in the brain. Both involve some of the same regions of the brain, in what is known as the frontostriatal system. Disorders that arise from this region are thus known as frontostriatal disorders,[3] which include ADHD and ASD. Recent neuropsychological evidence[4] suggests that ADHD and ASD share some similar brain circuits and both involve problems with managing cognitive processes and emotions, self-control, and executing complex tasks (collectively known as executive dysfunction), implying that both disorders may have some underlying similarities.
References
- ^B Kadesjö, C GillbergThe comorbidity of ADHD in the general population of Swedish school-age childrenJ Child Psychol Psychiatry.(2001 May)
- ^C Gillberg, E BillstedtAutism and Asperger syndrome: coexistence with other clinical disordersActa Psychiatr Scand.(2000 Nov)
- ^J L Bradshaw, D M SheppardThe neurodevelopmental frontostriatal disorders: evolutionary adaptiveness and anomalous lateralizationBrain Lang.(2000 Jun 15)
- ^Belinda A Gargaro, Nicole J Rinehart, John L Bradshaw, Bruce J Tonge, Dianne M SheppardAutism and ADHD: how far have we come in the comorbidity debate?Neurosci Biobehav Rev.(2011 Apr)