The article indicates that working memory can be improved though, going to have to give that a try.
Honestly, I don't find I have much of a problem with working memory. Sure, my ability to recall a meaningless number several minutes later is absolutely terrible, but a handling an analysis or conversation about a complicated subject (complex is a different matter that relies on raw intelligence more than working memory) with lots of important detail seems to be easier for me, to the point where other people tap out with "information overload" when I'm moving along just fine.
Of course, executing a complicated process is a whole different matter, because the ADHD brain quickly loses interest and focuses on something else.
All through the test I felt like I was crushing it. Spacial reasoning, pattern recognition, memory tasks. When the results came back I got 135 on spatial reasoning but 89 on processing speed and working memory.
Looking back on my life I realize I had always made up for limited working memory with systems, mnemonics and other techniques. When you've lived your whole life with a limitation you can have a huge blind spot. You've never known what it's like to have "normal" working memory.
My working memory is also hopeless with context switching. If I'm juggling three contexts at once, odds are I will lose working memory of all three (or was it four? ;-).
When I look back at my life, I've absolutely had to compensate for all that, but most of the "compensation" is just acknowledging the limitations. Memorizing dates and times just isn't going to happen (add time blindness compounds the problem), names of people & places are going to be impossible, etc. The closest thing I have to a compensation technique is the crutch that is hyperfocus.
However, when it comes to information (i.e. data that has some kind of meaning), I seem to be able to do much better than most, to the point where people often remind me that I need to consider that everyone else isn't able to keep all that context in their head at once. I can't speed read, but I can digest material with complex subject matter, analyze complex problems, etc. just faster and seemingly more easily than a lot of people. Some of that is likely due to other factors, but working memory is definitely an asset.
I remember a close friend getting frustrated administering a working memory test on me. She couldn't believe how far removed from the norm my working memory capacity was given everything else she knew about me.
What you say about being more easily distracted is a side effect of impaired working memory for example.
For me, executive disfunction is the most significant issue; and that compounds the problem of limited working memory by wasting it on irrelevant stimulus.
I know it is over-diagnosed because high school and college kids want to to tweak legally. But it makes it harder for those of us that actually suffer with ADD
I mean, just give the Wikipedia a go to learn about the scope: https://en.wikipedia.org/wiki/Attention_deficit_hyperactivit...
But the implication of neurotransmitters in causing ADHD is not merely hypothetical. ADHD is polygenic, i.e involving many sifferent genes. But in genetic studies, many of the genes found to he most correlated with ADHD were directly involved in monoamine neurotransmission, and many of those relate to dopamine. These include the genes for the D4 and D5 receptors, the dopamine transporter(DAT), which is responsible for dopamine reuptake(and also one of the targets for ritalin), TAAR1, which regulates synaptic monoamine release(this is targeted by amphetamine), and various enzymes involved in monoamine metabolism or synthesis(MAO-A, COMT, DBH).
There's also some involvement of serotonin and noradrenaline related genes like SERT, the serotonin 1b receptor(which, big surprise, is involved in mediating dopamine in PFC), the adrenergic alpha 2a receptor(which is targeted by the adhd meds clonidine and guanfacine), and some more enzymes.
So the genetic evidence for the involvement of dopamine is quite strong. There's also some evidence from brain imaging studies, showing that long-term treatment with central stimulants(which primarily act on dopamine and noradrenaline) leads to reduced abnormalities in brain structure. In addition there's mountains of evidence for the effectiveness of stimulants in managing the symptoms of ADHD.
In conclusion, the role of dopamine ADHD is backed up by a lot of empirical data. Doesn't make it the only factor involved, but it's certainly an important one, and not merely hypothetical.