The Emotive Power of Voice

Our voices are a critical part of human communication, but it turns out there’s actually still a lot we don’t know about how our brains perceive and produce the emotions that we convey through voice.

A new study dove into this arena, focusing on the one voice that most people inevitably hear all the time—your own. “You can’t escape it,” laughs Jean-Julien Aucouturier, a researcher with the French National Centre for Scientific Research (CNRS) at IRCAM (Institut de Recherche et Coordination Acoustique/Musique) in Paris, France, and a lead author of the paper. The results, published in the Proceedings of the National Academy of Sciences (PNAS), suggest that the emotions carried in your voice can influence your overall emotional state.

For this experiment, about 100 participants were asked to answer simple questions about their emotions—whether they felt happy or sad or afraid—and then read a short story out loud. They could hear their own voice through headphones as they were reading. Afterwards, they were asked to rate their emotions again using the same questionnaire. (Participants were not told that reporting their emotions and reading the story were part of the same experiment.)

What participants didn’t know is that the pitch of the voice they were hearing in their headphones was actually slightly modified to sound happier, sadder, or more fearful (the higher the pitch, the happier someone sounds, for example, while a tremble in the voice conveys fear or anxiety). The researchers found that participants whose voice had been modified to sound happy reported significantly more positive moods than controls, and those whose voice was modified to sound sadder reported corresponding sad moods. The findings suggest that not only do we use our voice to communicate emotions to others, but we actually listen to our own voice to glean information on how we’re feeling.

The findings suggest that not only do we use our voice to communicate emotions to others, but we actually listen to our own voice to glean information on how we’re feeling.

“Normally, you sound like how you feel. Here, we created a strange, otherworldy situation where people sounded different than how they originally felt,” Aucouturier wrote in a later email. “You could have expected that people could say, ‘wait, that’s not how I’m supposed to sound,’” but instead, the participants in this study ended up changing their feelings to match what they had heard.

“This is a completely novel finding,” says Aucouturier, and it could inspire future research avenues. “Voice is amazing in terms of the amount of information it conveys,” he says. For example, perhaps our voice channels traits and attitudes, such as confidence or disdain, that can influence the way we behave.

Aucouturier and his colleagues developed a new audio platform specifically for this experiment, in which they could input a participant’s voice, modify it, and then play it back to the person—all within a moment’s time—to create the illusion that the participant was hearing their normal voice speak through headphones. (It usually takes just 1 or 2 milliseconds for us to “hear” our own voice; in this platform, the voice modification takes about 20 milliseconds, but that’s still fast enough that few participants seemed to notice—only 16 said they could tell that their voice had been modified, and their results were removed from the final findings, according to Aucouturier.)

“What really blew us away is the potential of the tool,” wrote Aucouturier. In experiments designed to study behavior, there’s a risk that participants will notice the methods being used to manipulate their behavior, which can affect results. But in this experiment, the majority of participants were unaware. Where psychological research is concerned, “we could be looking at the ultimate tool for emotion regulation here.”

The researchers have made the platform open-source so that anyone can experiment with it.