Popular myth did not get it right on lefties

It would be hard to argue that Leonardo da Vinci, Albert Einstein, Napoleon Bonaparte, Winston Churchill, Henry Ford and Pelé did not reach the absolute peak of their chosen field of endeavour.

But, according to new study, they did so against the odds; they were (or are) all left-handed.

The research runs contrary to popular perceptions that lefties tend to be more talented than their right-handed peers. The author of the new study says that this mistaken belief is based on unrepresentative anecdotal evidence such as the fact that four of the last seven US presidents - including Barack Obama - have been left-handed.

In fact, Joshua Goodman, an economist at Harvard's Kennedy School, has found that southpaws, who account for roughly 12% of mankind, have many disadvantages.

In his study - The Wages of Sinistrality: Handedness, Brain Structure, and Human Capital Accumulation - Goodman writes: "Lefties exhibit economically and statistically significant human capital deficits relative to righties."

He argues that this is still true even when you take into account factors such as infant health and the subject's family background.

He writes: "Compared to righties, lefties have more emotional and behavioural problems, have more learning difficulties such as dyslexia, complete less schooling, and work in occupations requiring less cognitive skill."

He points out that left-handedness has long been viewed with suspicion.

"During the Middle Ages left-handed writers were thought to be possessed by the Devil, generating the modern sense of the word sinister from sinistra, the Latin word for left.

"The English word 'left' itself comes from the Old English 'lyft', meaning idle, weak, or useless. The French word for left, gauche, also means clumsy or awkward."

But why do left-handed people suffer these disadvantages?

Goodman suggests that there are two types of lefty: those whose left-handedness is in their DNA and those whose left-handedness appears to have been caused by trauma during their mothers' pregnancy .

Left-handers whose mothers were also left-handed - genetic left-handedness - do not suffer from the differences in cognitive ability, but Goodman found that the right-handed children of left-handed mothers appear to have "cognitive deficits".

" Mismatch between the handedness of parents and kids might be as important as handedness itself," he wrote.