When an epiphany strikes, it's rare and fleeting. Something clicks in our minds, and what was once confusing is suddenly obvious, illuminating, and even exciting.

Such moments are not purely internal events, it turns out. Our eye movements and pupils can broadcast these "aha!" moments, making it possible to predict epiphanies even before they occur, a new study found.

Scientists at Ohio State University conducted the research. They wanted to better understand what happens in people's heads as they make various types of decisions -- an area of study known as neuroeconomics.

In this fledgling field, researchers have tended to focus on how people respond to feedback and gradually, deliberately adjust their thinking as they learn. But few studies had looked at so-called epiphany learning.

"We had this intuition that there are situations where you don't figure things over time -- it sort of comes to you all of a sudden," said Ian Krajbich, a co-author of the study and assistant professor of psychology and economics at Ohio State.

"There was a gap in what we know about that kind of learning," he said in an interview.

For the study, published Monday in the Proceedings of the National Academy of Sciences, Krajbich and doctoral student James Wei Chen enlisted 59 students.

Participants played a relatively simple game on a computer against an unseen opponent. Beneath the screen, a camera monitored where the player was looking on the computer and tracked their pupil dilation.

The screen showed 11 numbers (0 to 10) arranged in a circle like a rotary phone. In the game, each participant picked a number. The researchers then took the average of those two numbers and multiplied that by 0.9. Participants had to guess what the resulting number might be, and one opponent was deemed the winner.

If that gives you brain cramps, you're in good company.

To win the game, it turns out, all participants had to do was guess a lower number than their opponent.

"If you think of it that way, the obvious strategy is to pick zero, because zero is always going to be the smallest number," Krajbich explained.

Participants played the game 30 times in a row, always against a new opponent.

For 42 percent of the participants, a light bulb flipped on at some point. Eye tracking data showed a sudden change in their behavior. After choosing other numbers, their eyes remained fixated on the lowest numbers. These players no longer looked at their opponents' number and instead studied the outcome of each game. As their strategy formed, their pupils dilated.

Soon after this, the students made a firm decision. They clicked a specific button that committed them to using zero in every upcoming game. Participants didn't mull over whether or not to click a particular button during multiple games -- they only looked at it once, and pressed enter.

"That tells us they were building up confidence over time. They had no interest in committing until all of a sudden, they had that epiphany and jumped right to zero," Krajbich said.

About 37 percent of participants did commit to using the same number, but they didn't pick zero, which suggests they didn't actually learn the game-winning strategy, the study found. The remaining 20 percent never committed to a number, and probably needed a drink afterward.

The study doesn't prove that some people have epiphanies while others don't. Additional research and different types of games and challenges are needed to answer those types of questions.

Krajbich said he and his research partners would like to devise settings where they could observe multiple epiphanies within the experiment, and focus more on what happens physically in those "aha!" moments through brain imaging and other methods.

However, the early results do suggest that, in order to experience epiphany learning, we must look inward and focus on our own strategy, rather than scrutinizing the moves of our opponents.

"One thing we can take away from this research is that it is better to think about a problem than to simply follow others," the professor said. "Those who paid more attention to their opponents tended to learn the wrong lesson."