Brains have evolved over half a billion years with robust negative feedback loops that return to homeostasis. In the natural world in which they were evolved, they work pretty well to attend to what needs a response, and to respond appropriately, then return to a state of attentive vigilance.
But the system can be fooled. The feedback loop can be short-circuited. The brain can be disconnected from the real world and hot-wired for repetitive behaviors that create signals for repetitions of those same behaviors. This is a positive feedback loop, a runaway monster that has escaped the brain's control system. The possibility for such monsters is probably inherent in the design of the system. You can always change a (stable) negative feedback loop into an (unstable) positive feedback loop by crossing the wires.
I was going to speculate that alcohol was the earliest addictive re-wiring of the brain. Alcohol, in many but not all people, creates a desire for more alcohol. But then I realized that the strategy of rewiring the brain is very old indeed. The liver fluke Dicrocoelium, swallowed by an ant, spawns a brain worm that causes its host to climb blades of grass over and over, greatly increasing the odds that the ant will be eaten by a sheep or cow, whose liver can be infected by the fluke. Many parasites are known that take over the brains of their hosts to their own advantage.
175 years ago, British and American entrepreneurs addicted 3% of the Chinese population to opium, for their own fun and profit, then fought and won two wars for their right to do so. Tobacco companies hired chemical engineers and experimental psychologists to design cigarettes that were maximally addictive.
This introduction brings us to the main focus of this article: Today, cocaine and SSRIs and caffeine and oxycontin and prescription amphetamides are all dwarfed by a global pandemic addiction to social media.
Here is Chamath Palihapitiya, former vice president of Facebook, speaking at Stanford last November:
Our business model was about exploiting the psychology of mass populations...
I feel tremendous guilt. I think we all knew in the back of our minds, even though we feigned this whole line of "there probably aren't any really bad, unintended consequences," I think in the deep recesses of our minds, we kind of knew something bad could happen. But I think the way we defined it was not like this. It literally is at the point now where we have created tools that are ripping apart the social fabric of how society works. I would encourage all of you as the future leaders of the world to really internalize how important this is. If you feed the beast, that beast will destroy you. If you push back on it, we have a chance to control it and rein it in. It is a point in time where people need to hard-break from some of these tools and the things that you rely on. The short-term dopamine-driven feedback loops that we have created are destroying how society works: No civil discourse. No cooperation. Misinformation. Mistruth. And it's not an American problem. This is not about Russian ads. This is a global problem.
So, we're in a really bad state of affairs right now, in my opinion. It is corroding the core foundations of how people behave with one another. Bad actors can now manipulate large swaths of people to do anything they want. It's a really, really bad state of affairs. And we compound the problem. We curate our lives around this perceived sense of perfection, because we get rewarded with short term signals--hearts, likes, thumbs up, and we conflate that with value and with truth. And instead what it really is is fake, brittle popularity, that leaves you more vacant and empty than before you did it. It forces you into that vicious cycle, where you ask, "what's the next thing I need to do now? I need to get it back."