Monday, May 7, 2012

Speech lab: Unlocking the secrets of the human voice

It's an unusual performance. As James Wilkes reads aloud one of his poems, he slurs, stutters and stammers, struggling to get the words out. It's a far cry from his usually fluent readings of the material he knows so well. But today, James is taking part in an experiment at University College London's Speech Communication Lab. As he reads, his voice is played back to him through headphones just a fraction of a second later. And it is remarkably disruptive. He says: "It's a very, very odd experience. "It's like you are not saying words you have just said, so you are waiting for them to come. "The concentration involved is huge." Two cultures The writer has just taken up a poet-in-residence role at the Institute of Cognitive Neuroscience where the speech lab is based. He is hoping to get a creative insight into the science behind speech. "Everyone speaks, but it is something that is also really complex and strange," he explains. "The work they are doing at the lab is shedding some kind of light on that complexity and strangeness. And as a poet I really want to be part of that." The experiment that James has just taken part in is called Delayed Auditory Feedback (DAF), which is also known as speech jamming. Professor Sophie Scott, who heads the research group, says that it's a simple test that is helping to identify the mechanisms of speech. She explains: "What this is telling us is that when we speak, we make a noise, and if we fiddle around with that noise, it can make speech production difficult. "So it is telling us something interesting about how we use the sound of our own voice to guide speech output." Brain waves How we produce - and perceive - speech is the focus of research at the lab. Professor Scott says: "Speech is incredibly complex. "In fact, as a sound, speech or the human voice talking is comfortably the most complex sound you encounter on a day-to-day basis." She explains that just by hearing a few words, you start to build up an image of what a person might be like. "Our voices convey an awful lot of information about us, whether we want them to or not," she says. "If you couldn't see me, but hear me, you'd probably have a good guess at my sex, my age, where I come from, aspects of my mood and my socio-economic status - all of this is expressed in my voice. "But all sorts of other stuff too, like my aspirations and my hopes and what I'd like you to think of me. "I can guarantee to you that I sound different to talking to you here because I am trying to come across like a serious academic than if I was buying something a the market." The team is investigating the science behind speech in a variety of ways, from comparing recordings from around the world to see how communication varies across continents, to MRI scans that allow the researchers to identify which parts of the brain are activated as volunteers speak and listen to speech. And of course, as with any self-respecting cognitive neuroscience lab, behavioural experiments such as speech jamming feature too. In another test, Professor Scott asks James to read a text with her, out loud. It seems deceptively simple, but as they begin to read they have to synchronise everything: pauses, rhythm and even breathing to keep in time. Prof Scott explains that the simple experiment helps to reveal more about the complexities that exist in conversations. She says: "If you actually look at people together, they will start to coordinate their behaviour a lot to make conversation. "People will start to pronounce words in the same way, they'll coordinate their breathing. "Speech is actually a very, very complex social behaviour." James, who is spending several months with the speech team, is organising performances and events, such the Voices series of talks that will take place at UCL in April and May, to share what he is learning at the lab. But he also thinks it will have an impact on his own poetry. "[With speech jamming ] I found it changed the texture and the surface of what I was doing. I was slurring and stuttering, and those extra bits are really interesting to me as a poet," he explains. "It's something that is disruptive, it's unnecessary, excessive - and that to me is the material I want to work with." Prof Scott also thinks the poet's presence could have an impact on the way her team approaches their research. "You always learn something new from working with people who've got a different perspective," she says. "Psychologists tend to deal with speech as a disembodied language system, but the actual sounds of your language are incredibly important and have a lot to do with how you understand and interpret what people are saying to you. "And I think poets have a great deal of insight into that and a lot to say about the way we deal with the sounds people make around us." ________________ References: Morelle, Rebecca. 2012. "Speech lab: Unlocking the secrets of the human voice". BBC News. Posted: April 23, 2012. Available online:

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