You may think the fine art of conversation is all about the words you speak. But research suggests your eyes have something to say, too, letting others know when it's their turn to pipe up.

Turn taking in conversation is a topic of high interest to scientists because it happens so quickly—much faster than our brain is thought to be able to comprehend the words being spoken. Studies stretching back to the 1960s hint that we use eye gaze as a possible turn-taking signal. Yet until recently, such conclusions were usually based on simple, highly controlled interactions or observations of individuals on just one side of a conversation, explains Tom Foulsham, a psychology researcher at the University of Essex in England.

In an effort to track back-and-forth glances over time during more natural conversations, Foulsham and his colleagues at the University of British Columbia attached video eye-tracking devices to 40 individuals, who paired up in groups of two to play 20 Questions or Heads Up!—a Taboo-like word-guessing game.

Although the two games spurred slightly different conversation dynamics, researchers consistently saw eye-gaze patterns akin to those described previously: individuals typically averted their gaze from the listener while speaking, looking directly at them as they wrapped up their talking turn, according to the report in August in PLOS ONE. Listeners, meanwhile, maintained a more constant focus on the speaker but looked away as they shifted into a talking role.

“There's this kind of dance that people do,” Foulsham says. “It's not just about looking someone in the eye—it's also about looking away from them.”

It remains to be seen how these eye-gaze cues differ depending on the familiarity, rapport or personality traits of conversationalists and the nature of their discussion. Still, such studies may eventually help in everything from improved video conferencing to understanding the communication consequences of altered eye-gaze patterns in individuals on the autism spectrum.