We all make spontaneous hand movements, called gestures, when we talk. These cospeech gestures are produced in rhythm with our speech and are related to the meaning of what we are saying. For example, when talking about attending a piano recital, you might move your fingers right and left in front of you to illustrate what playing a piano looks like.
There are several different types of gestures that serve different purposes. Some gestures describe objects or actions, like the piano example above. These are called iconic gestures, because they create a picture. Sometimes our gestures do not make pictures, but they move in rhythm with our speech. These are called beat gestures, because they follow the beat of our speech. For example, you might flick both wrists downward when saying the word amazing in the following sentence: "The recital was amazing." These gestures can help the speaker emphasise certain words.
Hand gestures are not just hand waving. Gestures can also enhance learning in children who view and make them. Children's gestures reveal when they are on the cusp of understanding a new concept. An important unanswered question that scientists are still trying to figure out is how? How do gestures help learning? Even though we do not yet have an answer to this, scientists have some ideas. One possibility is that gestures offer a visual way to communicate ideas that can complement what children hear or say with spoken language. Instead of just hearing something in speech, children get to see it as well.
Another possibility is that gestures help children focus their attention on the most important points of what is being learned, at exactly the right time. Gestures increase the chance that the children will know exactly which part of the equation the teacher is talking about. Finally, it is also possible that gestures help memory by engaging more parts of the brain. Gesturing engages the motor parts of the brain in addition to the parts of the brain already active for producing language. Engagement of multiple brain areas may lead to better, deeper learning.
Gestures come along for free with our speech and can play a critical role in helping children learn. By continuing to study gestures, we will better understand how we can help children learn.