I was just looking at the Association for Psychological Science website and found that the current issue of their periodical is on the links between psychology and neuroscience. I took a class from one of the authors of one of the articles. It made me regret leaving grad school for a moment. I thought--and I still think--that these problems are really interesting, even important. I had wanted to do something about it.
But I don't regret leaving really. Staying wouldn't have made me happy. It might have gotten me a tiny corner in this area, if I'd stayed in the program and if I'd gotten a postdoc in something I actually wanted to do, rather than something that sounded vaguely interesting and was the only place I felt I could go. But it wouldn't have given me the wider understanding of the general problem, which is what I really wanted, I think. And I know I wasn't what a graduate school wants out of a grad student: 110% dedicated, willing to put up with politics and late nights and demeaning jobs, willing to put my head down and delve into a tiny niche and never come back up for air. I still don't know what I want entirely, but I really do think I'm happier reading such a publication than contributing to it.