Why do some people hold on to their accents all their lives while others drop them overnight? Sophie Scott, a neuroscientist from University College London, has spent 16 years researching speech: how we formulate words, how we come by our accents and how we decode what is being said to us.

To help her understand how our brain negotiates the complex task of talking, Professor Scott has enlisted the help of the television impressionist Duncan Wisbey, a regular on Alistair McGowan’s Big Impression and the voice of Migo on the Fimbles spin-off, the Roly Mo Show. By scanning Wisbey’s brain she discovered that much more of the brain is involved in talking and learning speech than researchers previously thought. The results will be presented at a public event in London next week as part of Brain Awareness week.

Professor Scott speaks in a soft southern accent, despite growing up in Lancashire. “There are so many things that can influence why we have an accent; for example, how your parents spoke and how much you identify with your parents,” she says. She hopes that by working out how impressionists use their brains to learn to mimic people, new techniques could be developed and used by speech therapists to help patients with communication problems. “We’re going to look at the brain anatomy of people who have voice artist skills to see if parts of their brains are slightly larger than people who haven’t got these skills,” she says. “I want to find out why some people are better at doing accents than others.” You meet some people who never seem to have lost their accent, while other people seem to change theirs at the drop of a hat.”

But does Professor Scott think that different accents affect our brains in different ways? Possibly. Although the same brain areas would be activated whether we were speaking in a Yorkshire or Welsh accent, the areas may be activated to different degrees. “Some accents stress different properties of speech production. Some make you use a different range, intonation or rhythm. Others make you move your mouth in a different way,” she says.

Turning actions into words

Professor Scott’s brain scans of Duncan Wisbey (see panel below) revealed that a large part of developing a new accent comes from the areas of the brain that control our movements. She suggests that if someone wants to develop a new accent, they may want to imagine a person with that accent and then think themselves “into the skin” of that individual.

Neuroscientists are divided on the precise details of how the brain enables speech, but it is generally accepted that when we want to communicate, two processes occur in our brains. One part thinks about what we want to say and so formulates words, sentences and grammar. Another region then puts all of this into action, coordinating the many muscles and movements required to produce words and sounds.

While lying as still as possible in a brain scanner at UCL’s Institute of Cognitive Neuro-science, Wisbey was asked to repeat easy-to-remember phrases such as “Humpty Dumpty sat on a wall” in rapid five-second bursts. A monitor visible to him via a mirror inside the scanner give his prompts to say the phrase either in a regional or foreign accent, or as an impersonation of a celebrity, over an hour and a half.

While the scan took pictures of his brain activity, recording equipment noted the voice or accent he was using. The results showed clearly that four different parts of his brain were being activated. Only two of these were connected with speech and language, and Professor Scott was confused.

She then realised that the other two areas were connected with movement. These regions, responsible for visualising images and for body movement, were working overtime when the impressionist was forming his speech. Wisbey was literally thinking himself into someone’s skin when he was adopting a different accent.

Anyone who has ever watched an impressionist knows that the performers always act out the mannerisms of the person they are mimicking. But this finding is crucial because it shows that people who are forced to relearn speech, such as stroke victims, may find this process easier if they think of their voice as coming from their whole body, not just their voice box, says Professor Scott. “Only half of the activations in the brain were to do with the speech and language areas. The voice is not just coming from your lips. It’s coming from the whole body and you need to think about that when you’re trying to change aspects of it.”

As a result, Professor Scott began thinking that voice coaches for actors may hold the key to helping speech therapists develop exercises for people with communication problems.

Helping speech problems in stroke patients

One third of people who suffer a stroke experience language difficulties, including complete loss of speech. Other causes of communication difficulties can include dementia and head injury. Andrea Lane, a spokeswoman for the Stroke Association, says that waking up from a stroke, disorientated and unable to speak, is a horrific experience.

“The best way to describe it is having a word on the tip of the tongue that you just can’t find. It’s very frightening and frustrating to come to after a stroke and realise that you can’t tell the doctor and those around you how you’re feeling,” she says.

Lane says that speech and language therapy help. Group work is used, as is individual therapy and computer-based exercises, which provide a mental workout. This helps to build up the unharmed parts of the brain so they can take over from the damaged parts. Speech therapists can also teach people new ways of communicating, such as using gestures or writing. However, a poll this week by the Royal College of Speech and Language Therapists revealed that only half of those who survived strokes felt that they had received adequate speech therapy.

Professor Scott believes that her research into the brain and accents may prove useful in her work with stroke patients. As a result of suffering a small stroke, some patients develop a speech impediment known as foreign-accent syndrome, which can seem as if they are speaking with a foreign accent.

“To our ears they sound as if they’re not a native speaker of English,” she says. “It occurs all over the world, and the consensus is that it has a lot less to do with them developing a new accent and much more to do with us labelling what we hear. Interestingly, if I play a tape of an English person with the syndrome to someone who is not a native English speaker, they don’t hear someone with an accent, they hear someone with a speech impediment.”

Professor Scott says: “The patients hate the fact that they sound so different. If they really try, they can sound a bit like they used to, but it’s very difficult.”

Celebrity endorsement

Wisbey will continue to help Professor Scott with her work, and may have even lined up a famous impressionist to take part in her next study, although she won’t disclose who.

“It would be great that my ability to do ridiculous voices didn’t end up a silly thing I did at parties but actually helped someone with speech difficulties,” says Wisbey.

And Professor Scott knows never to underestimate the power and importance of a person’s voice: “Our identity is bound up with it.”

The Talking Brain event will be held at the Bloomsbury Theatre, Gordon Street, London WC1, on Tuesday. To register, e-mail Rosalyn.lawrence@ucl.ac.uk. For more information about strokes, contact the Stroke Association: www.stroke.org.uk, 0845 3033100

A head for words

A scan of Duncan Wisbey’s brain shows the areas activated when he spoke.

1. Supplementary motor area Used when he sounded words to himself without moving his lips.

2. Sensory-motor strip Activated when he moved his mouth, face and body.

3. Intraparietal sulcus Lit up when he was rehearsing words before he said them.

4. Anterior temporal lobe Activated when concentrating on the sound of his voice.

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