If you give your mouse a lever to stimulate its own reward center — literally with a wire — it will press on the lever repeatedly as much as possible, even at the expense of eating and drinking (and probably be happy doing it ). This was an experiment for wireheading — artificially stimulating the reward center of the brain.
We are closer and closer to the ability of doing that to ourselves.
The level of stimuli we currently receive is very far from what the brain evolved for: our food has much more sugar than our ancestors', we can listen to any kind of music while our ancestors had limited access to concerts once in a while at best (and our music tends to be much more stimulating and aggressive than theirs), we can look at things our ancestors could only try to imagine. The last one is especially strong: moving colorful things are stimulating for our brain, we have much more of them now than in the ancestral environment, and apps like TikTok can optimize very well for what you want to see. And it's working: if you start consuming one of those stimuli, you have to actively consciously stop yourself from continuing. If you're able to read several paragraphs of text while you have the ability to watch content engaging on a more primal level — you're already a hero (a lot of people gave up already).
However, this issue becomes paramount when discussing neural interfaces — devices that can read and influence neurons. It is likely that in the observable future we will be able to do literal stimulation of the reward center, so the question is, won't we all wirehead?
The solution to that lies in Jhanas: Buddhist meditators already figured out how to turn on the pleasure centers, and they are mostly fine! Jhanas are highly pleasurable mental states from Buddhism achieved by pure meditation. The way I understand it from 'Hidden Views on Mountain Fuji' by Pelevin, the first four Jhanas are an ascent through increasingly subtle states of pleasure and tranquility. In the first three, you achieve increasingly more pleasurable meditative states, and in the fourth you transcend even the feeling of happiness, but it feels like a better state than before. Point is, when you return to normal life, it doesn't feel like you've been to a great state and then returned to mundane reality, but, in some sense, you realize that reality was kind of a peak all along.
The reward center is deeper in the brain than the regions responsible for higher brain functions, which means we'll actually access jhanas earlier than pure wireheading. This makes me very hopeful about neural interfaces: we'll have the ability to wirehead ourselves, but we'll choose not to, because we'll have the means to access the "high" states of consciousness and realize that normal life (especially enhanced with BCIs) has been the best state all along.