Aspects of mixed-handedness

Recent research at Imperial College London, reported in the journal Pediatrics, suggests that ambidextrous children could be up to 90 per cent more likely to suffer academic and behavioural problems than their right-handed counterparts, who are considered the norm. About 1 per cent of the population is ambidextrous, and the researchers were keen to stress that, although the results were statistically significant, the actual numbers of children affected remained small.

Questionnaires were completed by the children, their parents and their teachers, and comparisons made between right, left and ambidextrous children. They found that, in seven- to eight-year-olds, left-handed children were 30 per cent more likely than the norm to have problems with mathematics, while ambidextrous children were 90 per cent more likely to have similar problems than their right-handed counterparts. By the age of 16 the ambidextrous group reported having greater difficulties with languages and were twice as likely to suffer attention deficit-hyperactivity disorder (ADHD).

It is well known that handedness is linked to the hemispheres of the brain, with the left hemisphere being stronger in right-handed individuals and vice versa for left-handers. Handedness can be used as a rough guide to the functioning of certain areas of the brain, and in ambidextrous individuals brain function is thought to differ from that of the normal population, and it has been suggested that this could explain the link to ADHD, since the condition is associated with problems in processing information in the right side of the brain.

Ambidexterity can be used to advantage, however, particularly in certain sports. Some ambidextrous individuals have been known to perform spectacular feats. The ancient Greeks encouraged their soldiers to train in the use of both hands because of the obvious advantage in battle.

Historical figures who were ambidextrous include Albert Einstein, Leonardo da Vinci and Michelangelo, who painted with both hands, changing when one arm became tired. Mahatma Ghandi was reportedly able to write in a different language with each hand simultaneously.