According to UC Berkeley researcher Juliana Schroeder, she and University of Chicago researchers Nicholas Epley and Michael Kardas were inspired to look into this idea after one of them read a news article that included a speech excerpt from "a politician with whom he strongly disagreed" (but who remained nameless). "The next week, he heard the exact same speech clip playing on a radio station," Schroeder told the Washington Post. "He was shocked by how different his reaction was toward the politician when he read the excerpt compared to when he heard it. When he read the statement, the politician seemed idiotic, but when he heard it spoken, the politician actually sounded reasonable."

They decided to delve into this phenomenon. For a study published in Psychological Science, the researchers sat six people in front of a camera and recorded them as they gave their (actual) opinions on three polarizing topics. Two argued for a pro- or anti-abortion stance, two argued for or against the U.S. war in Afghanistan, and two advanced their views on the most timeless issue of all: rap versus country music.

Next, they presented online participants with the messages, with one twist: each participant was randomly assigned to either watch and listen to the video, listen to just the audio, or read only the transcript of the message. Afterward, the participants had to rate the speaker on their intellect and emotional warmth, saying how "refined and cultured," "rational and logical," "superficial," and "mechanical" they were, among other things.

When the participants read opinions they disagreed with, they tended to "dehumanize" the person, judging them as more mechanical and less responsive and warm. That wasn't true when they watched or listened to them: in both cases, people judged their opposition as more "humanlike."

The same thing happened when the team repeated the experiment with people arguing for their preferred U.S. Presidential candidate, and when Schroeder and Epley presented hypothetical employers with pitches from job candidates: the applicants whose pitches employers heard, rather than read, were more likely to be hired.

"When two people hold different beliefs, there is a tendency not only to recognize a difference of opinion but also to denigrate the mind of one's opposition," the researchers wrote. You obviously can't read your opponent's mind, so you pick up on other cues. When all you have is text, there are fewer cues to pick up on, so they're easier to dehumanize.

If you want your ideas and opinions taken seriously (and seriously, who doesn't?) this has huge implications. In a world where many of us type more than we speak, it's important to recognize the shortcomings of text communication. We've already written about how people are more likely to honor a request that's made in person than one made in text form, and more research is showing just how deep that schism goes. Just because our technology has evolved doesn't mean our brains have caught up — they're as keen on the human voice as ever.

But advancing technology is a double-edged sword. There are more and more ways to communicate with friends and publish your ideas via audio and video these days. If you have an idea that's too valuable to dismiss, remember what science says, and use your voice.

For more on how to make people see things your way, hear our chat with persuasion expert Lynne Franklin on Curiosity Podcast episode 21, Get People to Do What You Want.