Long stigmatized, left-handers nevertheless have a unique brain. A study from the University of Oxford reveals that they have a specific cognitive talent, often absent in right-handed people.
For centuries, being left-handed was frowned upon, even a handicap to be corrected. Today, around 9 million French people are left-handed. This particularity would have advantages that right-handers might envy, according to a large study carried out by researchers at the University of Oxford.
Based on genetic and brain data from 400,000 individuals, researchers suggest that the brains of left-handers do not function quite like those of others. These genetic variants directly influence the structure of the cytoskeleton, the internal scaffolding of cells. They noticed that these genetic instructions changed the organization of white matter in the brain. It is therefore not only a question of dominant hand, but a fundamentally different neuronal architecture which takes shape from the fetal stage.
This is where the famous “quality” revealed by the study resides: greater verbal agility. As Dr Akira Wiberg, lead author of the study published in the journal Brain, explains: “Left-handed people have an advantage when it comes to completing verbal tasks“. Concretely, this means that they have a great capacity to find “the right words” and to use their vocabulary with more ease. They are also capable of processing a greater flow of information and manage to make new associations of ideas, which promotes eloquence, distribution and originality of speech.
Where a right-hander will tend to process language in a very lateralized way (mainly in the left hemisphere), the left-hander mobilizes his two “processors” in perfect harmony. This biological particularity explains why some left-handers demonstrate great oratorical ease or particular agility in wordplay and rhetoric, even if researchers remain cautious about the systematic application of this observation to each individual.
Beyond this verbal capacity, this research work rehabilitates the place of left-handers in human diversity. By linking genetics, brain structure and cognitive abilities, the Oxford study shows that handedness is an essential component of the richness of our species. “Left-handers are born with unique wiring, etched into their cells by a team of genes, making their brains structurally different from those of right-handers“, specifies Professor Gwyneth Douaud, professor of neuroscience at Oxford. Further proof that our physical differences often hide unsuspected brain capacities.
