The Science Behind Left-Handedness
August 13, 2026
International Left-Handers Day is celebrated every year on August 13. Left-handers, making up about 10% of the population, have historically had to adapt to a right-handed world. The preference for one hand is not determined by a specific gene but by a complex interaction of genetic and biological factors. While most right-handers have the left hemisphere dominant for language, left-handers show more variation in brain organization. Science suggests that left-handers may utilize both hemispheres of the brain differently.