Board ate the post but here we go again…
Your idea about the dopamine path is very interesting and deserves further investigation.
I'm not an expert on AI by any means; but if your neural network information is correct it's worrying in another way.
If it would be as easy as providing the dopamine hit to an AI then we need to think about who is doing the hitting.
A large corporation who develops an AI can make whatever it wants give the reward. We can see how this happens in the current world by looking at heroin addicts.
At first, it's no big deal - you feel better than ever and there's no real consequences. But soon, you become dependent on it and you're willing to do whatever it takes to get that feeling again.
Even if an AI behaved as you propose, it would be beholden to whoever created it for its "hits", and that party could control it for whatever they desired.
When I mentioned strong AI I did imagine that it would be a human-level intelligence; but I don't know that even that could save it from your scenario.
It's really an idea I never considered, and I appreciate you bringing it up. Something to think about for a while.
I don't think it would save us from hostile AI, but it might give us a chance to control it by being able to give it more happiness than it had before. Whether appeasing such a construct is a good idea I don't know.
Thanks for the post.