One area of interest is creative cognition. In particular, one type of creative cognition is exemplified by “insight” solutions to problems. These are the solutions that are accompanied by “Aha” or “Eureka” experiences. It’s as if a light turns on and you suddenly see an answer to a problem that had stumped you. Sometimes this happens when you didn’t even know you were thinking about the problem.
A series of behavioral and neuroimaging experiments has begun to de-mystify this process, and reveal how the brain produces insight. PLoS Biology published two experiments with Ed Bowden and John Kounios. We gave study participants a series of word problems to solve. Subjects got three words like:
face
table
game
For each problem, the solution is a single word that can form a compound word or phrase for each of the words (e.g., “mind” or “piece” could both work with game, but neither works for all 3; the actual solution is at the bottom of this page). Sometimes people solve these with insight (Aha!) and sometimes through straightforward solving methods. We let subjects (after training) tell us how they solved each problem. While they solved 124 (or more) of these problems, we recorded brain activity with fMRI or EEG, with two separate groups of subjects. Both experiments pointed to important involvement of the same brain area: The anterior Superior Temporal Gyrus of the right hemisphere. No insight effect was observed anywhere within the temporal lobe of the left hemisphere.
We had predicted this area might be involved because it seems also to be important for drawing distantly related information together when comprehending complex language. This is just what is needed to overcome impasse and solve a problem with insight. This fMRI result is also consistent with previous results from our lab demonstrating RH advantages in solution priming (fast responses to solution words) and solution decisions, for words presented to the RH, via the left visual field, compared to words presented directly to the LH, via the right visual field (Beeman & Bowden, 2000; Bowden & Beeman, 1998; Jung-Beeman & Bowden 2003).
The EEG experiment provided two additional pieces of information. First of all, the RH temporal lobe activity appeared as a sudden burst of high-frequency (gamma band) activity, relative to solutions achieved without insight. This neural activity is often associated with complex cognitive processing, in particular binding elements of a percept together as it comes into a consciousness.
A second, unexpected EEG effect also was observed: About 1.5 seconds prior to insight solutions, an increase in lower frequency (alpha band) activity appeared over the right posterior cortex. This effect disappeared precisely when the high-frequency activity began over the right temporal lobe. This may reflect “gating,” or attenuation, of visual input, allowing initially weak solution-related activity to gain strength, then burst into consciousness as an insight. This is like closing your eyes so you can concentrate when you are trying to solve a difficult problem but in this case, your brain is blocking out just the visual inputs to your right hemisphere.
We are extending this work with different types of problems, different tasks that allow us to assess component processes, and with assessment and induction of different moods to examine how these moods alter neural systems and cognitive processing.
The answer to the example problem? Card (face card, card table, card game).