Change Your Voice to Change Others’ Minds

With traditional face-to-face communication on a hiatus during the COVID-19 pandemic, we are being forced to rethink how we communicate important messages. How should we attempt to influence other people if they can only hear our voice or see a small video of our face in the corner of their computer screen?

Many of us agonize over crafting the perfect language to win over audiences. However, research has revealed that many of the approaches we often use to try to persuade other people—such as using rhetorical questions and superlatives—often backfire. When people hear language that reveals that others are trying to persuade them, their first impulse is often to question the communicator’s sincerity and tune out the message. Although stringing together the perfect words during an upcoming conference call or Zoom meeting might seem like the best approach for persuading others, it often doesn’t work.

Fortunately, our words aren’t the only tool at our disposal. We can modify our voice by doing things such as raising our volume, lowering our pitch, and speaking at a faster rate. These vocal features, called paralinguistic cues, convey important information about our attitudes.  

Our research demonstrates that strategically modifying one’s paralinguistic cues can be an effective way to persuade other people. Across a series of experiments, we asked research participants to record themselves reading a message that contained a recommendation aloud twice—once as they normally would and another time in a manner that could persuade others. We later had a separate sample of participants listen to audio-only versions of these recordings and then make a choice about whether to follow the speaker’s recommendation.

Trying to persuade through paralinguistic cues worked. Compared to their normal way of speaking, speakers who read the messages in a way that they thought would persuade other people were more successful at convincing others to follow their recommendations. And remember that the speakers read exactly the same message each time, so differences in how persuasive the speakers were across recordings must have been due to their use of paralinguistic cues. 

But how did speakers change their voices—their paralinguistic cues—when they were trying to be persuasive? When speakers attempted to persuade others, they spoke louder and varied their volume to a greater degree. This made them seem more confident, which enhanced their persuasiveness. Interestingly, this occurred even though listeners could detect that the speakers were trying to persuade them through their paralinguistic cues. But, rather than undermining speakers’ sincerity, using paralinguistic cues to persuade others actually increased speakers’ perceived sincerity.

Another study compared these paralinguistic persuasion attempts with linguistic attempts in which, instead of modifying properties of their voice, research participants focused on modifying the words they used to  persuade other people. As in our other studies, speakers were more persuasive when they modified their paralinguistic cues. In contrast, linguistic persuasion attempts—merely changing the words they used—did not make speakers more persuasive.  This effect occurred despite the fact that changing the content of a message during persuasion attempts, like paralinguistic changes, made audiences realize that the speaker was trying to persuade them.  

Does this mean that you should abandon all efforts to fine-tune the language you plan to use in your next important pitch? Not necessarily. Speakers in our studies were well-educated and moderately persuasive even when they were not channeling their efforts into crafting persuasive language. Thus, investing effort to be comprehensive, coherent, and clear all make sense. We certainly did this while writing this blog.

But when a person can hear your voice, rather than obsessing over trying to find the perfect words, you might be better off channeling your efforts into how you deliver the message. By using your voice to project confidence, you should be more persuasive.

For Further Reading

Van Zant, A. B., & Berger, J. (2020). How the voice persuades. Journal of Personality and

Social Psychology, 118(4): 661-682.

Alex Van Zant is an Assistant Professor of Management & Global Business at Rutgers University–Newark and New Brunswick

Jonah Berger is an Associate Professor of Marketing at the University of Pennsylvania.