FEB 24, 2021

Vocal Markers for Trust and Reliability are Easily Manipulated

WRITTEN BY: Annie Lennon

Why is it that some voices instinctively sound more reliable than others? Researchers have found that we identify specific patterns of speech (known as prosody) subconsciously- and that these influence our perception of how trustworthy someone is. 

Being able to trust and rely on others is crucial for cooperation and communal life. Some have thus argued that humans possess dedicated mechanisms for deciphering truth from others. In this way, humans would be better equipped to ensure that potentially dangerous falsehoods don’t spread. How exactly these truth-seeking mechanisms work, however, has remained largely unexplored. 

For the first experiment within the study, researchers recruited 20 native French speakers to compare the certainty and honesty of 880 pairs of computer-generated pseudo-speech. The pitch, loudness, and duration of the pseudo-speech (made up of pseudo-words) were manipulated at random, and the French-speakers partook in the experiment twice with a week in between. The researchers also conducted the same experiment three more times on other people from different linguistic backgrounds, including German, English, Marathi, Russian and Spanish. 

In the end, they found that aspects of speech, including falling pitch and volume at the end of a word and a faster speed rate, tend to be seen as more reliable. Importantly though, the researchers say that these signs of trust’ can be manipulated and thus used by a deceitful speaker to coerce. As such, they say that there is no mandatory marker for dishonesty, something which is also supported by previous research investigating the speech patterns of people who are lying.

From participants with various linguistic backgrounds, the researchers further found that perception of reliability comes regardless of an individual’s native language or conceptual knowledge and that listeners extract this information automatically. They additionally found that the prosodic signature of speech impacts the way spoken words are memorized. 

 

Sources: Nature Communications