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What do Leonardo da Vinci, M.C. Escher and Jimi Hendrix have in common? They're just a few of the creative geniuses also known for being left-handed, helping to fuel the widespread belief that lefties are more creative.

It's a compelling idea that even scientists presumed to be true—but it's not, new Cornell psychology research finds.

Scouring more than a century of studies that explored links between handedness and creativity, the researchers discovered not only that left-handers are not naturally more creative, but they are underrepresented in the most creative fields compared to right- or mixed-handers—art and music being two exceptions.

"The data do not support any advantage in creative thinking for lefties," said Daniel Casasanto, associate professor in the Department of Psychology and College of Human Ecology, and director of the Experience and Cognition Lab. "In fact, there is some evidence that righties are more creative in some laboratory tests, and strong evidence that righties are overrepresented in professions that require the greatest creativity."

Casasanto is the senior author of "," published in the Psychonomic Bulletin & Review. Owen Morgan, a doctoral student in the field of psychology, is the first author, and Siyi Zhao, M.A. '22, is a co-author.

Casasanto said there are scientific reasons to believe that left-handed people, conservatively estimated to comprise about 10% of the population, would have an edge in creativity. Divergent thinking—the ability to explore many possible solutions to a problem in a short time and make unexpected connections—is supported more by the brain's right hemisphere.

One prior study found participants performed better at divergent thinking tasks after squeezing a ball with their left hand, compared to their right hand or no hand. That suggested motor activity controlled from the right hemisphere was kindling nearby areas responsible for creativity. If so, Casasanto said, it could be that southpaws (or "sinistrals") essentially go through life repeating this experiment—juicing their creativity every time they pick up a pen, paintbrush or screwdriver.

Planning to test that idea, the researchers conducted a meta-analysis—crunching the data from many previous studies—that sorted through nearly 1,000 relevant scientific papers published since 1900. Most were weeded out because they did not report data in a standardized way or included only righties (the norm in studies seeking homogeneous samples), leaving 17 studies reporting nearly 50 effect sizes.

The meta-analysis revealed that handedness made little difference in the three most common laboratory tests of its link to divergent thinking; if anything, righties had a small advantage on some tests.

"If you look at the literature on the whole," Casasanto said, "this claim of left-handed creativity is simply not supported."

Additional meta-analysis confirmed that left-handers are overrepresented among artists and musicians—but not architects, as is often claimed. Expanding their investigation beyond those fields, the team re-analyzed data from a large study drawing upon U.S. government surveys with information on occupations and handedness. The data included nearly 12,000 individuals in more than 770 professions, which were ranked by the creativity each required.

By this measure, combining "originality" and "inductive reasoning," physicists and mathematicians ranked alongside fine artists as the most creative jobs. When considering the full range of professions, the researchers found, left-handers were underrepresented in those that required the most creativity.

What has sustained belief in left-handers' special creativity? One factor, the authors speculate, is left-handed exceptionalism: the idea that it's rare to be a lefty and rare to be a creative genius, so perhaps one explains the other. Another is the popular perception that creative genius is linked to mental illness. It turns out lefties, who are more likely to be artists, experience higher rates of depression and schizophrenia.

"This idea that left-handedness, art and mental illness go together—what we call the 'myth of the tortured artist'—could contribute to the appeal and the staying power of the lefty creativity myth," Casasanto said.

Finally, Casasanto said, the urban legend is a case study in statistical cherry picking—frequent citing over the years of a small number of studies with small or biased samples.

"The focus on these two creative professions where lefties are overrepresented, art and music, is a really common and tempting statistical error that humans make all the time," Casasanto said. "People generalized that there all these left-handed artists and musicians, so lefties must be more creative. But if you do an unbiased survey of lots of professions, then this apparent lefty superiority disappears."