When your thinking is interrupted by your brain, you've got real ADD.
When it's interrupted by the world, you just have trouble saying "no."
True ADD is about having your concentration (mind) interrupted from inside your brain, because the resting "idle" of your brain cells is too slow. When the resting "R.P.M." of your brain is too slow, your mind does not become engaged. You're left functioning from your reptilian brain, reacting more by reflex than by reflection.
Natural adrenaline (which is triggered by excitement and risk, as in extreme sports, trading, speculating and selling) raises the resting R.P.M. of your brain enough to engage your mind (think of needing to get your manual transmission car's engine beyond 800 R.P.M. or else it will stall). When your mind is engaged, it doesn't think faster; it thinks more clearly, because it is able to tune out extraneous stimuli and avoid becoming distracted so easily.
Although this makes you more goal-directed, it causes you to be less empathic to others. That's why people with natural ADD (especially young children) often have trouble being sensitive to others. It is not that they are insensitive (i.e., intentionally and purposefully that way); it is just that they are not sensitive. Problems arise in relationships when your being unintentionally not sensitive to others is taken personally by them.
The way medications like Ritalin, Dexedrine and Adderall work is that they lesson the need of people with true ADD to seek out excitement and adrenaline-rush-type activities to be able to engage their minds. It also allows them to able to listen more patiently, benefiting their relationships. Being able to relate becomes possible, whereas being able to achieve was the only option before.
I first coined the term "pseudo-ADD" 12 years ago, before my suffering from it took me down multiple paths (which makes me diversified on good days, and scattered on bad ones). It occurs when your mind is not interrupted by your brain but by the emotional needs of and demands from people outside you.Rather than being unempathic, you are too empathic and will drop what you're concentrating on to attend to the needs of others (what the word "codependent" means). You have trouble tuning out the outside world with pseudo-ADD and suffer from what I call "concentration interruptus." The treatment for pseudo-ADD is not medication but learning to set clearer boundaries between you and other people and internalizing it so that you don't feel guilty (for hurting others) or afraid (for upsetting others) when you say "no."