Before the midterm elections, politicians have bombarded voters with ads and speeches. One neuroscientist says that their hand gestures may make all the difference in how we perceive their message. This ScienCentral News video has more.

Talking Hands

In the 2000 presidential campaign, many observers labeled Al Gore as stiff. Lauren Solomon, an image consultant, has worked with politicians and executives for 13 years on how to handle themselves in public speaking situations. She thinks the problem wasn't just his language, it was his body language.

"If you don't believe that there is a link between your words and your gestures, then you're only going to get half of the languaged message across to your audience," she says.

Colgate University neuroscientist Spencer Kelly found that hand gestures actually influence how our brain processes speech. "Some people think that gestures are actually separate from language," he says. "I believe they are part of language and that means if you're going to understand language, you can't just focus on speech, you have to focus on speech and gesture."

Discovered in 1980 by University of California, La Jolla, researchers Marta Kutas and Steven Hillyard, the N400 effect is a signature negative brain wave with a peak at approximately 400 milliseconds after the final word is spoken. "If you say, 'the man likes cream and sugar in his socks,' the brain finds that to be unusual," says Kelly. "It doesn't make sense given the sentence ... So the N400 reflects a violation of your expectation of what a word should be."

As featured in Scientific American Mind, that suggests that the brain sees gestures as an integral part of communication. Without them, our brains only get part of the story. According to Kelly's paper, may be integrated into the brain in early or late stages of language processing.

Kelly, a self-proclaimed "prolific gesturer, for better or worse," theorizes that gesturing can be good for both people trying to communicate information and for audiences trying to understand that message. "Hands aren't just good for changing tires, or writing letters, hands are also good for thinking. And when you're speaking, these things are ripe for the taking," he says.

Volunteers heard the word "tall" while watching a video of a hand moving towards a short glass. Kelly observed the N400 effect during these gesture mismatches. image: Colgate University

So his advice to politicians: "It's probably safe to keep to the scripted gestures." But when they go off the script, like during a debate, he says that politicians should make sure that their gestures speak along with their words.

He says teachers can also use this advice when introducing new words to their kids, whether it's a foreign language teacher saying a new word or other teachers introducing new ideas. "If students' brains are wired up to connect gesture and speech, you better use gestures with your speech to best increase learning for those children."

Kelly's future research will look at how we change our communication style when we can't gesture, like when we talk on the phone.

Kelly's research was featured in the October/November 2006 issue of Scientific American Mind and published in Brain and Language, April 2004. This study was funded by Colgate University.