By Katherine Gombay
We may not look much like them – but we have a lot more in common with finches than we may imagine. And two professors in the biology department, Sarah Woolley and Jon Sakata, are hoping to gain some insight into the neural basis of human communication disorders by studying how songbirds, such as zebra and Bengalese finches, learn how to sing.
“People think that when they hear birdsongs and calls, that it’s all genetically encoded,” says Jon Sakata. “But juvenile songbirds go through same process of vocal learning as people do – they listen to adult exemplars, then they experiment, just as babies do when they babble, and then they use auditory feedback to hone their vocal motor skills and learn how to communicate. It’s very similar to what you see in humans.”
Woolley and Sakata, who recently received a grant from the Canada Foundation for Innovation (CFI) under the Leaders Opportunity Fund, are particularly interested in studying how songbirds integrate social signals as well auditory information as they make choices and learn how to sing. “It’s a bit like in people, where you look at what the cool kid is doing and think that you should be doing that as well,” explains Sakata. “Songbirds are highly influenced by social signals, so they’re more likely to imitate a dominant male that is paired with a female, rather than a subordinate male that is without one. What we want is to look at social signals like these and see how the brain processes this information to influence vocal learning.”
Because the neural circuits responsible for vocal communication in songbirds are already well mapped, Sakata and Woolley have been able to design experiments that will measure not only how songbirds learn and remember how to sing, but also how social signals influence this learning process. One of these experiments involves, quite literally, teaching juvenile songbirds to sing by playing recordings of other males to them and having them watch how adult females respond to these songs. The hypothesis is that juveniles will preferentially learn the songs that females show more interest in. By studying how the neural circuits in the songbird brain are activated by these social cues, the researchers hope to gain some insight into what goes on in human brain areas that mediate speech learning, social cognition and auditory memory. And they hope to learn something about human communication disorders such as autism in the process.
While it may sound like quite a big jump from songbird brains to human ones, according to Sakata, because of the striking parallels between birdsong and various aspects of human communication, it’s not unlikely that birdsong offers some important clues about the evolutionary building blocks of human speech.
Now if only we could stop talking and learn how to sing like them.