Children with matching pairs of hands are quicker-witted than those who are less symmetrical, research has shown.

They are able to react faster in mental tests, even after accounting for age and gender differences, scientists found.

The findings suggest a link from an early age between body symmetry and brain performance.

Previous studies have shown that men with more symmetrical faces are likely to experience less mental decline as they age.

Lead researcher Ian Deary, director of the Centre for Cognitive Ageing and Cognitive Epidemiology at the University of Edinburgh, said: “The connection between physical symmetry and reaction times could be an important clue to health and well-being over a person's life course.

“This finding can shed light on how the mind and the body develop together from childhood to older age.”

The scientists studied 856 children aged four to 15 whose hand symmetry was measured using a digital scanner.

Reaction times were assessed by means of a computer test.

Bodily symmetry could be a sign of biological fitness, experts believe.

It has been linked to health and multiple measures of well-being.

Previous studies have suggested that reaction times are an important indicator of health, and speed up significantly as children approach adulthood before slowing down as they approach older age.

David Hope, from the Centre for Medical Education at the University of Edinburgh, said: “This finding links cognitive ability and health very early in the life course - even before school age physical actions are connected with a person's body then reflected in mental function.”

The study is published in the journal Developmental Psychology.