That's a Strong Statement

Being in a position of power can fundamentally change the way you speak, altering basic acoustic properties of the voice. Listeners are able to pick up on these vocal cues to know who is really in charge, according to new research published in Psychological Science, a journal of the Association for Psychological Science.

We tend to focus on our words when we want to come across as powerful to others, but these findings suggest that the way our voice sounds also plays an important role.

“Our findings suggest that whether it’s parents attempting to assert authority over unruly children, haggling between a car salesman and customer, or negotiations between heads of states, the sound of the voices involved may profoundly determine the outcome of those interactions,” said psychological scientist and lead researcher Sei Jin Ko of San Diego State University.

Channeling Margaret Thatcher

The researchers had long been interested in the properties of speech, but it was former UK Prime Minister Margaret Thatcher that inspired them to investigate the relationship between acoustic cues and power.

“It was quite well known that Thatcher had gone through extensive voice coaching to exude a more authoritative, powerful persona,” Ko explained. “We wanted to explore how something so fundamental as power might elicit changes in the way a voice sounds, and how these situational vocal changes impact the way listeners perceive and behave toward the speakers.”

Ko, along with SDSU psychologist Melody Sadler and Adam Galinsky of Columbia Business School, designed two studies to find out. Their research was partially supported by Ko's grant from the Dispute Resolution Research Center at Northwestern University.

In the first experiment, they recorded 161 college students reading a passage aloud and captured their baseline acoustics. The participants were then randomly assigned them to play a specific role in an ensuing negotiation exercise.

Students assigned to a “high” rank were told to go into the negotiation imagining that they either had a strong alternative offer, valuable inside information, or high status in the workplace, or they were asked to recall an experience in which they had power before the negotiation started. Low-rank students, on the other hand, were told to imagine they had either a weak offer, no inside information, or low workplace status, or they were asked to recall an experience in which they lacked power.

The students then read a second passage aloud, as if they were leading off negotiations with their imaginary adversary, and their voices were recorded. Everyone read the same opening, allowing the researchers to examine acoustic properties while keeping the spoken content constant across all the participants.

Loud and clear

Comparing the baseline recordings to the experimental readings, the researchers found that the voices of students assigned to high-power roles tended to go up in pitch, become more monotone (less variable in pitch), and become more variable in loudness than the voices of students assigned to low-power roles.

“Amazingly, power affected our participants’ voices in almost the exact same way that Thatcher’s voice changed after her vocal training,” Galinsky said.

And the students’ vocal cues didn’t go unnoticed. A second study with a separate group of college students revealed that listeners, who had no knowledge of the first study, were able to pick up on these power-related vocal cues to determine who did and did not have power: Listeners ranked speakers who had been assigned to the high-rank group as more likely to engage in high-power behaviors, and they were able to categorize whether a speaker had high or low rank with considerable accuracy.

In line with the vocal changes observed in the first experiments, listeners tended to associate higher pitch and volume variance with high-power behaviors. They also associated overall louder voices with higher power.

“These findings suggest that listeners are quite perceptive to these subtle variations in vocal cues and they use these cues to decide who is in charge,” Galinsky said.