FRIDAY, Jan. 7 (HealthDay News) -- The hand gestures you use while talking can actually shape your thoughts, a new study suggests.

U.S. researchers had volunteers solve a puzzle called the Tower of Hanoi, in which they moved stacked discs from one peg to another. After completing the task the participants talked about how they did it, an explanation that required the use of hand gestures.

The participants then tried the problem again. But they didn't know that the weight of the smallest disk, which used to be light enough to move with one hand, now required two hands.

This change in weight caused problems for people who had used one hand in their gestures when talking about moving the small disk the first time. They took longer to complete the task than those who had used two hands in their gestures. The more one-handed gestures a person used when talking about doing the task the first time, the longer it took to complete the task the second time.

The findings suggest that gesturing helped the volunteers cement their knowledge about how to solve the puzzle and they were thrown off by the unknown weight change in the smallest disk, said University of Chicago psychological scientists Sian Beilock and Susan Goldin-Meadow.

The study appears in a recent issue of Psychological Science.

"Gesture is a special case of action. You might think it would have less effect because it does not have a direct impact on the world," Goldin-Meadow said in an Association for Psychological Science news release. But she and Beilock believe it may have a strong effect "because gesturing about an act requires you to represent that act."

More information

Here's more on nonverbal communication.