Alexandra Jaegy / Photo credit: THOMAS TRUTSCHEL / PHOTOTHEK / DPA PICTURE-ALLIANCE VIA AFP 11:46 am, August 13, 2023

If the France has nearly nine million left-handers, many legends persist around this particularity. On the occasion of World Left-Handed Day, Europe 1 looks at the concrete differences between left-handed and right-handed people, eternal rivals of everyday life.

DECRYPTION

What do Lady Gaga, Barack Obama and Angelina Jolie have in common? You can now imagine that they are all left-handed, just like about nine million French people. Using scissors, shifting car gears, writing... So many tasks that can be more complex for left-handers. And for good reason: they are only 10% of the world's population and therefore live in a world made by and for right-handed people, explains Peggy Gérardin, a researcher in neuroscience at Inserm.

>> READ ALSO – "I send at least two a month", despite the rise of digital, the postcard is resistant

All a bit asymmetrical

"Left-handers do not have a particular advantage, but rather a disadvantage. The child, then the adult, since he is in a world of right-handers, for certain tasks, he will have to reframe himself. When you are left-handed, you realize it very well. They complain about it and we understand them, "says the researcher. We now know that it is the right hemisphere that controls the left hand and vice versa, without any scientist yet knowing why.

And the very notion of right-handed lefties is to be nuanced, according to Peggy Gérardin. "Scientists wonder why there are left-handers. But in fact, we also know very well that we are all a little bit asymmetrical: never really completely right-handed, never completely left-handed. This is very rare in the general population. People call themselves left-handed, right-handed with the acquisition of writing. You can swipe with your left hand actually, without even realizing it," she adds. It is therefore impossible to scientifically say that left-handers would be smarter or better at sports. For example, Rafael Nadal is right-handed in his daily life, but left-handed on a tennis court.