Scientists believe they have isolated the part of the brain that determines how good children are at maths.

Researchers at the Institute of Child Health at Great Ormond Street Hospital, London, found that children who were bad at calculation had a reduced amount of grey matter on the left hand side of their brains.

Grey matter is the name given to areas of the brain that are mainly composed of the heads of nerve cells.

Researchers studied 80 children who had been born prematurely.

They used brain scan images to examine anatomical abnormalities on the left parietal lobe in the children.

'Fruitful research'

It revealed the difference in grey matter between children who were good and bad at calculation.

Dr Elizabeth Isaacs, who led the study, said the research did not mean that all children with calculation problems would have the same parietal lobe anomaly.

"Imaging studies will be needed for a broader range of children," she said.

However, since the area identified has also been implicated in adult studies, it seems a fruitful area for further research.

"Diagnosis in individual children and perhaps remedial methods are an interesting area of speculation."

The results were published in the journal Brain.