[grepLeigh]

Eh, if you hadn't found Stumbleupon then you would have experienced the same effect from one of the zillion other competitors in the attention economy.

You're right that this kind of novelty-seeking content has a profound impact on the brain. It's really interesting to see finally see longitudinal research, plus research on screens/novelty on child development (search for $thing + "psychosocial development").

One of the most encouraging thing I've taken away is that neutral pathways are still quite plastic well into adulthood.

For example, here's an experiment to try if you wake up and scroll in bed. After you do your morning routine, jot down a mood score (-1 feeling crummy, 0 meh neutral, +1 feeling good). You can do this for a week or two if you want to collect control data. Then, force yourself to get out of bed without looking at your phone (buy an alarm if you have too). You should see changes in your mood log within a week. Sleep regulates/replenishes dopamine levels, and scrolling through a dopamine wonderland first thing in the AM can result in dopamine dysregulation for the rest of the day. Try it!