Dopamine is a neurotransmitter released by the "reward" system in the brain. I quote mark reward because what dopamine actually does is stimulate you to take action due to the anticipation of a reward not the actual gratifying feeling you get when you have the reward in hand.
It's what causes yearning.
When you look at it this way, dopamine can kind of suck. You wouldn't desire anything if you didn't have dopamine, which means you could never be disappointed when you don't get it. Of course, you wouldn't get a lot of things at all either.
I've been struggling with the Law of Attraction and every Self Help books advice that you must fully experience and feel the thing you want for it to manifest into your life. You must anticipate it coming, you must expect it coming.
Dopamine tells you, "Hey, do this and you'll get something in the future," but the future doesn't exist until it happens, aka until it's the present. As Kelly McGonigal puts it, "Evolution doesn't give a damn about happiness itself, but will use the promise of happiness to keep us struggling to stay alive."
It's interesting when you contrast this info with what we know about ADHD. According to medical research ADHD is a reduction of standard of dopamine and norepinephrine production. Because you don't anticipate any reward in the future, you simply say "Meh, not interested." As a true ADHD child I can attest to this my entire life. The medical community also came up with a solution for this: feed them drugs to stimulate the production of dopamine and norepinephrine. I will also vehemently attest to the absolute destruction of the mind this solution results in.
Let's jump to the more recent spiritual/woo-woo interpretation of ADHD and the Indigo Children. Most Indigos are ADHD and their lack of interest in most traditional subjects is simply due to an evolutionary jump in what is actually important in this world. Turns out that if you put an Indigo on specific tasks they have relentless attention and can far outpace "traditional" minds. I will also attest to this as fact, to me at least.
It really comes down to what it is you desire. People with ADHD evidently desire different things so that when we present traditional subject matter, they just aren't interested.
You do have the ability to control the future, you control the future by living in the now. You control the now by choosing what you desire. You control what you desire by creating the future in your mind, now.