How a raise of an eyebrow is worth a thousand words

Scientists are hoping to learn more about how children respond to facial expressions by monitoring their reactions to Wallace and Gromit.

Scientists are hoping to learn more about how children respond to facial expressions by monitoring their reactions to Wallace and Gromit.

Researchers at Bristol University and Aardman Animations, makers of the Gromit films and hits such as Chicken Run, have begun an exploration of the science behind the recognition of emotions.

The scientists, who announced their plans at a meeting of the British Association for the Advancement of Science in Exeter yesterday, hope that by showing some of the films to children, they can gain an insight into how humans learn to "read" faces. And the animators think they can make their figures still more convincing.

"Gromit [the dog] is non-speaking yet young children engage with him strongly," said Professor Graham Collingridge, of the university's neuroscience department. "So the facial expressions he uses must link to some very basic communication. When he's sitting there rolling his eyes, you know that he's disapproving of [his owner] Wallace, without saying anything." In fact, Gromit has no mouth - which would seem to limit his range of expression even further. Gromit expresses himself purely through the movement of his eyes, eyebrows and ears.

"Psychiatrists are very interested in that," said Anne Cooke, of the university's neuroscience department. "We can also learn about childhood development, because children under five don't seem to understand that when older people lie, they find it hard to look someone in the eye. Below that age, children can tell bare-faced lies - such as being covered in chocolate while denying they've been eating it."

The fruits of the partnership might come in time to shape the studio's next big film in October next year, starring Wallace and Gromit. So far it has been four years in the making. "We've got 30 minutes of it in the can so far," said Arthur English, a spokesman for Aardman, explaining why the company is talking to the scientists.

"We believe realism in the face comes from the top of the eyebrows down to the chin. If you can be convincing there, then you will draw the audience into believing the character is real."

Mr English said that Aardman was not trying to compete with purely computer-generated films such as Shrek: "Our feeling is that we prefer our more earthy look; but with that, we're striving for more realism. And it's easier to get realistic facial expressions in plasticine than computer graphics."

Working with the scientists has brought Aardman some early benefits, showing that in producing animations for TV, less detail was required than for the cinema - allowing the company to halve the number of frames it produced. "Normally you'd produce 24 frames per second for TV," said Mr English. "But it turns out that the brain can't see the difference: you can get by with 12 frames per second on a TV." However, in the cinema, which runs at 25 frames per second, every frame must be produced individually to avoid jerkiness.