The difference is that this: > In ADHD, choices that would lead to short-term effort but only long-term reward (practicing an instrument, for example) are down

The difference is that this: > In ADHD, choices that would lead to short-term effort but only long-term reward (practicing an instrument, for example) are down-weighted. "You" want to learn to play the piano? Too bad; your brain doesn't. is the natural human condition. In the past they called it "building character" or whatever but it's always been an effort to get people to value the long-term reward vs. short-term. Drugs are just an alternative short cut to what used to be a decades long grind to build the ability to delay gratification.