Gibbon songs have regional accents, says new study

Call of the wild has different accents

Washingtonians who live close to the National Zoo know all too well about gibbon songs. The small apes begin calling out to one another every morning at dawn and again throughout the day whenever they switch locations, get a lot of visitors or just feel like hollering.

It turns out that some of those songs might have distinctive characteristics similar to accents, according to a recent study in the journal BMC Evolutionary Biology.

After analyzing samples from more than 400 gibbon songs, researchers at the German Primate Center in Goettingen found that the calls can be used to identify which species of gibbon is singing as well as the area it's from. The scientists were able to distinguish the sounds of apes from various parts of the dense rain forests of Cambodia, Vietnam and Laos, where gibbons live in the wild.

However, people living near the zoo won't be able to detect the regional differences without sophisticated sound analysis software; not even Lisa Stevens can do that, and she's been working with the zoo's gibbons for 33 years. Stevens, the zoo's curator of primates, says the songs of the six gibbons living there are very similar. The zoo has four white-cheeked gibbons: two males that were born there and two females that were brought in from the wild, probably from Vietnam. The females are "geriatric" now at ages 41 and 43, Stevens says. They came to the United States in the late 1960s or early 1970s from markets in Southeast Asia where people were selling them as pets.

The zoo also has two siamangs from the Malay peninsula.

Stevens was not surprised at the study's results, because regional variation in color and pattern of gibbon coats has already been established. She expects that there are also behavioral differences among gibbons from different regions. Gibbons sing to define their territory and to find mates, but Stevens suspects there's more content than that. "We're just scratching the surface of the information that they're communicating in gibbon calls," she said.
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References:

Saslow, Rachel. 2011. "Gibbon songs have regional accents, says new study". Washington Post. Posted: February 28, 2011. Available online: http://www.washingtonpost.com/wp-dyn/content/article/2011/02/28/AR2011022805262.html

Picture: Mehgan Murphy / National Zoo

Unfamiliar Accents Turn Off Humans And Songbirds

New research suggests that our brains have a built-in bias against people whose accents don't sound like our own.

That's the conclusion of Scottish researchers who presented their work at the Society for Neuroscience meeting in San Diego.

The team, from the University of Glasgow and the University of Edinburgh, used a functional MRI scanner to study the brains of 20 native Scots as they listened to native English speakers with Scottish, American and southern English accents. They focused on the brain's temporal voice area, which seems to specialize in processing characteristics of particular voices.

Earlier research had found that people process words spoken in their own accent more quickly and with less effort. So the team expected the brain scans would show a decrease in brain activity in this area.

Instead, the scans showed a "huge increase," says Patricia Bestelmeyer of the University of Glasgow.

Also, when the Scottish volunteers listened repeatedly to an American or southern English accent, their brain activity gradually diminished. But that didn't happen when they listened repeatedly to someone speaking in their own accent, Bestelmeyer says.

That suggests that people's brains are paying more attention to the voice of someone from their own group than from a different group.

From an evolutionary perspective, it makes evolutionary sense that our brains are wired to detect accents, Bestelmeyer says. "Accents convey important information about the speaker's social background," she says, adding that accents offer a quick way to determine whether someone is part of our own group or an outsider.

Songbird Accents

It's still not clear precisely how the human brain does all this, Bestelmeyer says. But, oddly enough, people who study birds think they may have some clues. That's because songbirds, like people, learn to vocalize early in life and develop regional accents. So research on bird brains could help explain what's going on in the human brain, says Jon Prather from the University of Wyoming.

Prather has studied the brains of swamp sparrows from Pennsylvania and New York, whose calls have subtle differences that are a lot like accents.

"We studied a region of the bird brain that is involved in not only how they sing their songs but how they perceive differences in their songs," he says. And that research found individual brain cells that would respond to one accent — but not another.

So Prather and researchers from Duke University compared songbirds from Pennsylvania with songbirds from New York. They found specific brain cells in the Pennsylvania birds that responded to songs sung in their own accent, but they would stop firing when exposed to a New York accent.

"It would effectively shut down. It would not respond at all," he says.

All of which suggests that that songbirds from Pennsylvania and New York recognize each other's speech differences much the way human residents do, Prather says. And in nature, he adds, members of one group tend to be wary of members of another.

"We think that's actually the reason that Eagles and Giants fans don't get along," he says.

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References:

2010. "Unfamiliar Accents Turn Off Humans And Songbirds". NPR. Posted: November 16, 2010. Available online: http://www.npr.org/2010/11/16/131359561/unfamiliar-accents-turn-off-humans-and-songbirds

Humans imitate aspects of speech we see

UC Riverside study finds that we sound like the people we talk with, even when we can't hear them

Humans are incessant imitators. We unintentionally imitate subtle aspects of each other's mannerisms, postures and facial expressions. We also imitate each other's speech patterns, including inflections, talking speed and speaking style. Sometimes, we even take on the foreign accent of the person to whom we're talking, leading to embarrassing consequences.

New research by the University of California, Riverside, published in the August issue of the journal Attention, Perception, & Psychophysics, shows that unintentional speech imitation can even make us sound like people whose voices we never hear. The journal is published by The Psychonomic Society, which promotes scientific research in psychology and allied sciences.

UCR psychology professor Lawrence D. Rosenblum and graduate students Rachel M. Miller and Kauyumari Sanchez found that when people lipread from a talker and say aloud what they've lipread, their speech sounds like that of the talker.

The researchers asked hearing individuals with no formal lipreading experience to watch a silent face articulate 80 simple words, such as tennis and cabbage. Those individuals were asked to identify the words by saying them out loud clearly and quickly. To make the lipreading task easier, the test subjects were given a choice of two words: e.g., tennis or table). They were never asked to imitate or repeat the talker.

Even so, the researchers found that words spoken by the test subjects sounded more like the words of the talker they lipread than did words they spoke when simply reading from a list. That finding is evidence that unintentional speech imitation extends to lipreading, even for normal hearing individuals with no formal lipreading experience, they wrote in a paper titled "Alignment to Visual Speech Information."

"Whether we are hearing or lipreading speech articulations, a talker's speaking style has subtle influences on our own manner of speaking," Rosenblum says. "This unintentional imitation could serve as a social glue, helping us to affiliate and empathize with each other. But it also might reflect deep aspects of the language function. Specifically, it adds to evidence that the speech brain is sensitive to – and primed by – speech articulation, whether heard or seen. It also adds to the evidence that a familiar talker's speaking style can help us recognize words."
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References:

EurekAlert. 2010. "Humans imitate aspects of speech we see". EurekAlert. Posted: August 5, 2010. Available online:http://www.eurekalert.org/pub_releases/2010-08/uoc--hia080410.php