​

Voice impressions: you can trust me (Image: webphotographeer/Getty Images)

For similar stories, visit the The Human Brain Topic Guide

We know that our voices can transmit subtle signals about our gender, age, even body strength and certain personality traits, but Phil McAleer at the University of Glasgow and his colleagues wondered whether we make an instant impression. To find out, they recorded 64 people as they read a passage. They then extracted the word "hello" and asked 320 people to rate the voices on a scale of 1 to 9 for one of 10 perceived personality traits – including trustworthiness, dominance and attractiveness.

Although it's not clear how accurate such snap judgements are, what is apparent is that we all make them, and very quickly. "We were surprised by just how similar people's ratings were," says McAleer. Using a scale in which 0 represents no agreement on a perceived trait and 1 reflects complete agreement, all 10 traits scored on average 0.92 – meaning most people agreed very closely to what extent each voice represented each trait.

It makes sense that decisions about personality should happen really fast, says McAleer. "There's this evolutionary 'approach/avoidance' idea – you want to quickly know if you can trust a person so you can approach them or run away and that would be redundant if it took too long to figure it out."

The impression that our voices convey – even from an audio clip lasting just 390 milliseconds – appears to be down to several factors, for example, the pitch of a person's voice influenced how trustworthy they seemed. "A guy who raises his pitch becomes more trustworthy," says McAleer. "Whereas a girl who glides from a high to a low pitch is seen as more trustworthy than a girl whose voice goes up at the end of the word."

It is possible to change some of these aspects of your voice, he says. "It has been rumoured that Margaret Thatcher and the Queen were both trained to make their voices appear more dominant." Some aspects though, are less malleable. For example, the shape of the vocal tract influences perceived dominance.

"The methods used in this paper are familiar, but the conclusions are novel and very interesting," says Jody Kreiman, who researchers voice perception at the University of California, Los Angeles. The way the study links personality to attractiveness and reproductive fitness makes sense biologically, she says.

The team hope that their work can be used to help create artificial voices for people who have lost their own due to a medical condition, as well as creating likeable and engaging voices for satnavs, and other robotics. "You might also use this kind of work to find the right person to front a team," says McAleer, "you don't want a really untrustworthy voice running your call centre."

Journal reference: PLoS One, DOI: 10.1371/journal.pone.0090779

Source: New Scientist URL: http://www.newscientist.com/article/dn25226-your-voice-betrays-your-personality-in-a-split-second.html#.UyfpS9IW3mU