When a child has a language delay, people tend to accept this fact at face value: Joseph is 6 but speaks like a 3-year-old. While understandably upsetting to many parents, no one expects Joseph to speak differently before he is able. There's a scramble to start services and a patient approach while allowing language to develop.
The same attitude does not hold for attention deficit/hyperactivity disorder (ADHD). ADHD is a developmental delay in a broad skill set called executive function. A huge body of research defines it as a medical disorder; neither parents nor children benefit when people suggest otherwise.
Executive function represents our capacity to self-regulate, encompassing everything from focus and impulse control to long term planning, prioritizing, organizing our lives and emotional control. It is required for social interactions and classroom learning. Imaging studies confirm that children with ADHD experience immature brain development, showing again that it's neither a child's fault, nor a parent's, nor society's.
A child with ADHD may be 6 years old but going on 3 when it comes to self-regulation. Often parents hear, or even feel themselves: He's just lazy. He needs to get his act together. He knows better. Yet inconsistency is inherently part of ADHD, with moments of clarity balanced by a perplexing inability to hold it together over an entire day. So he probably does know better -- but without typical executive function, lacks the skills of other children his age to follow up.
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