When I said "physiological fact", I meant to suggest a category including things like Down's Syndrome. I did not mean things like depression or other mental illnesses that may be observable using brain imaging and/or caused by physiological circumstances.
I won't get into the problems with trying to draw generalizations from brain imaging (easy enough to Google it), but I also have a problem with the idea that observable, physiological problems can't be fixed through behavioral means. We definitely agree on that.
> I can assure you that ADD has been a constant thing in my life for 39 years and that depression and anxiety have not been.
I should have been clear that I don't think ADD is only a symptom of depression and anxiety. I was just sharing the theory that ADD is a common symptom of many conditions, rather than a true condition in itself. In my experience, the cause has been depression and anxiety, but that's obviously not an exhaustive or scientific sample.
Or that, like many mental conditions, others can mask or appear to be ADD/ADHD. There are plenty of individuals diagnosed with ADD, in which it manifests as a singular facet to an otherwise normal mind. Then there are plenty where it's a manifestation of combinatory factors from other mental illness. It is important to note though, that even as a singular facet, many of the resultant symptoms of ADD overlap with depression, anxiety and Bipolar Disorder (depending on the individual); despite the different effects and regions of the brain targeted. I would actually argue that this is one of the main culprits of its overdiagnosis in the US.
I would recommend reading into Russell Barkley's work. He's one of, if not the, preeminent experts on the Attention Deficit scope of disorders and studied their effects on the brain and really defined the modern idea of what ADD/ADHD are.