Can you solve this problem?

Given a human being with an inoperable stomach tumor, and lasers which destroy organic tissue at sufficient intensity, how can one cure the person with these lasers and, at the same time, avoid harming the healthy tissue that surrounds the tumor?

For the solution and evidence from Laura Thomas and Alejandro Lleras (2007) that shows that moving your eyes in a specific way can help you solve the problem, continue reading after the break.

In the 1940's and 50's gestalt psychologists began to study what they termed insight problems, where once a crucial element of the problem is discovered people achieve the AHA! moment of sudden insight. One of the most famous of problems was the Karl Dunker Radiation Problem highlighted above. The solution to the problem requires the critical insight that you can shoot multiple low-intensity lasers from different places around the body so that they can converge on the tumor and destroy it without damaging skin that a single high powered laser would.

So what do eye movements have to do with this problem you ask?! This is where it really starts to get cool.

Eye-tracking research by Grant and Spivey (2003) showed that people who spontaneously solved the problem without any hints looked more often at the skin crossing area and made significantly more in-and-out eye movements radiating around the entire body than those who weren't able to solve the problem or required hints. This is called embodied cognition, or in other words some part(s) of your body reflects an internal mental process externally.

Thomas and Lleras (2007) wondered whether eye movements are just a reflection of internal problem solving or whether changing peoples eye-movement patterns could lead to more successful problem solving. With the knowledge that people solved the radiation problem more effectively when they made triangular crossings between the tumor and the skin Thomas and Lleras constructed a task that had participants making different patterns of eye movements during an unrelated task in which they had to follow numbers around the screen as they appeared (see the figure below).

What they discovered was that in the condition where participants made movement in and out of the body in a triangular fashion (figure B above), they successfully solved the radiation problem more frequently.

What's even more amazing about this result is that the participants did not even realize that their eye movements were contributing to their solving the problem. In fact, according to the researchers, "many believed the tracking task was a purposeful distraction from the radiation problem."

According to a press release from the Beckman Institute at the University of Illinois

"The theory that we're working with right now is the idea that when people do these sorts of movements it actually starts them on what's called a perceptual simulation," Lleras said. "The idea is that you basically use the same structures in the brain when you are thinking about doing something that you would actually use when you do that task. So we start them on this movement and that starts this simulation of how to solve the problem."

This of course is the quick and dirty final result - many other ways of analyzing the results are in the paper which is available here. I highly recommend reading this interesting paper in full! After all anyone who uses this really cool eye tracking setup has to do awesome research:

This is a report on: Thomas, L.E., & Lleras, A. (2007). Moving eyes and moving thought: On the spatial compatibility between eye movements and cognition. Psychonomic Bulletin & Review, 14, 663-668.