When people gesture with their hands while talking, it helps change their thoughts. If you ask someone to show you how to tie their shoe-laces or play Jenga, they will almost certainly use their hands to do so.
Even people who have been blind from birth, and have never seen gestures, still use them while they talk. But these gestures aren’t just a way of communicating, they may also be a way of abstracting and encoding the information.
In a study investigating how gestures interact with thoughts, Beilock and Goldin-Meadow (2010) had participants trying to solve a test often used by psychologists called ‘The Tower of Hanoi’ task.
Essentially this involves moving some blocks from one tower onto another.