April 21, 2004 -- We've all had those moments, from time to time, when the solution to a complex problem suddenly strikes out of thin air, providing an insight into something we've never understood before.
Cognitive scientists call it the "Aha!" experience. Or the "Eureka!" moment. You know you've had it because a mythical lightning bolt comes out of the sky, or a light goes off over your head, or you just feel euphoric.
Until now, many scientists had believed there's no fundamental difference between that Aha experience and any other cognitive process. But scientists at two universities, using some of the most valuable tools in their field, had found evidence that the moment when insight strikes is very different indeed.
Two different brain imaging techniques have revealed that a specific area of the brain "lights up" when the Aha moment arrives, according to cognitive neuroscientists Mark Jung-Beeman and Edward Bowden of Northwestern University and John Kounios of Drexel University. They reported their findings in the April 13th edition of PloS Biology, an online journal that is available free through the Public Library of Science.
"We believe this is the first research showing that distinct computational and neural mechanisms lead to these breakthrough moments," says Jung-Beeman. "This was the first real crack at it (understanding how insight occurs) in terms of looking at the brain."
Areas of Concentration
Participants in the study grappled with 144 simple problems, some of which required insight, and some of which could be solved without the need for a lightning bolt.
The researchers used functional magnetic resonance imaging, which allowed them to determine which parts of the brain were active, in the first of two experiments. Part of the brain "lit up" when the participants experienced Aha, but not when they didn't. The increased activity was observed in part of the right temporal lobe (the anterior superior temporal gyrus.)
The researchers were concentrating on that area because previous studies have linked it to complex language skills "when you need to tie together things that are distantly related," Jung-Beeman says. "That's exactly what an insight is. It's tying together information that people already know, but they don't recognize how they are related until that key moment."
That result was reinforced in the second experiment when an electroencephalogram (EEG) detected high frequency brain waves, normally associated with complex cognitive processing, in the same area of the brain.
The results show that some form of different neural activity is taking place during insight, but that's not likely to be the entire story, according to the researchers. This is a very new field, and it has eluded researchers for many years, so there are probably many other things going on in addition to one area of the brain lighting up.
But it's a strong start, according to other scientists who have looked at the work. Philip Johnson-Laird, professor of psychology at Princeton University, describes it as "one of the most original studies of insight that I have ever seen."
One of the problems confronting researchers has been pretty basic. How do you know when you've had a Eureka moment?
They looked to the past, and the character who coined the phrase, for an answer. Legend has it that Archimedes was just about to step into his bath when the light went off over his head. He had been ordered by his king, Hiero, to find out if his crown was pure gold without destroying it.
Archimedes noticed that the water rose in his bath as he stepped in, and the insight struck. The displacement of the water was directly related to the volume of whatever was put into the tub, even his foot, so all he had to do was submerge the crown in water to determine its purity.
And, as legend has it, Archimedes was so thrilled he shouted "Eureka," (I have found it) and ran home through the streets of ancient Greece without bothering to put on his toga.
The researchers figured that most people know when they've had an insight, so they relied on the participants to point it out.
"We defined it for them," Jung-Beeman says. "The answer comes to you suddenly. You weren't aware you were even thinking of it until the moment that it pops into your mind, and as soon as it does, you just know. It seems obvious."
Each problem consisted of three words. The participants were required to supply another word with a similar meaning, or that could be used to for a complex word, or phrase, with each of the three words. What goes with fence, card and master? Post. How about a little tougher one? Same, tennis, and head. The answer is match.
The idea was to give the participants words that are very distantly related, or not related at all, and see if they could complete the problem. Insight involves pulling together pieces of poorly related information and coming up with a solution.
The subjects solved 59 percent of the problems, and reported having an insight for 56 percent of the correct answers. And significantly, the two imagers recorded the heightened brain activity in the same area of the brain for those problems that were solved with insight, but not for the others.
Making the Connection
Like Archimedes, the participants combined previously known information in a new way, resulting to a solution to a problem.
"This is the nature of many insights," Jung-Beeman says, "the recognition of new connections across existing knowledge."
But, one might ask, so what? Why does any one need to know what part of the brain is involved in solving a problem?
Howard Gardner, professor of education and cognition at the Harvard Graduate School of Education, in commenting on the work, noted that it was a key part of trying to "demystify the creative process."
That could come in handy if the process stops working right. Maybe all it will take will be a tweak of that part of the right temporal lobe to get it working right again.
And maybe not. But at least it seems to be a step in the right direction.
Lee Dye’s column appears weekly on ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.