The prefrontal cortex has undergone a dramatic expansion during human evolution, so that it now represents nearly a third of the brain. While this area is often associated with the most specialized aspects of human cognition, such as abstract reasoning, it also plays a critical role in the insight process.
...Hallucinogenic drugs are thought to work largely by modulating the prefrontal cortex, tricking the brain into believing that its sensory delusions are revelations. People have the feeling of an insight but without the content.
-J. Lehrer, New Yorker, 2008
This reminds me of what happened to Paul McCartney of the Beatles at a party during the 60's when he apparently smoked a little too much marijuana. Here's what he says about it, conveying both the urgency of the feelings of revelation and his completely different perspective after he returned to reality as we know it:
“I spent the whole evening running around trying to find a pencil and paper because when I went back in the bedroom later, I discovered the Meaning of Life. And I suddenly felt like a reporter, on behalf of my local newspaper in Liverpool. I wanted to tell my people what it was. I was the great discoverer, on this sea of pot, in New York…
So I remember asking Mal, our road manager, for what seemed like years and years, ‘Have you got a pencil?’ But of course everyone was so stoned they couldn’t produce a pencil, let alone a combination of a paper and pencil, so it was I either had the pencil but I didn’t have the paper or I had the …[ellipses in original] I eventually found it and I wrote it down, and gave it to Mal for safekeeping.
I’d been going through this thing of levels, during the evening. And at each level I’d meet all these people again. ‘Hahaha! It’s you!’ and then I’d metamorphose on to another level. Anyway, Mal gave me this little slip of paper in the morning, and written on it was, ‘There are seven levels!’ …Not bad for an amateur. And we pissed ourselves laughing, I mean, ‘What the f***’s that? What the f*** are the seven levels?’”
-Paul McCartney, Many Years from Now (autobiography)
This doesn't mean that that "Eureka" feeling is always content-free. I'm assisting in a lab that does insight research right now, and they've shown plenty of evidence that people who say they solved problems with insight use a whole different process for correctly solving problems. (For an example of what I mean by a whole different problem-solving process, see Jung-Beeman et al., Neural Activity When People Solve Verbal Problems with Insight, PLoS Biology, April 2004). Seems like the feeling of insight is independent from the actual process of insightful problem solving. Maybe the feeling of insight (located in the prefrontal cortex) can connect with a number of different brain processes, all using different networks. For instance, it'd be interesting to compare the network you get in insight problem solving to that of empty "insight" like Paul McCartney experienced.
If the feeling of insight can go with multiple different processes, that's great for me. I have some theories about the feeling of insight outside the context of the problem-solving process my lab is studying. Maybe my hypotheses could work after all? ::crosses fingers::