NOTE: I will admit it - I am left-handed and was stigmatized as a child, especially in a parochial elementary school where the nuns were smacking my left hand for trying to write with it! This December 2016 article from Huff Post explains some of the challenges with being "left behind." Enjoy. As always, you can find all of my blogs from 2013 to the present on my website at https://stevemarshallassociates.com/steves-blog/
Lefties historically have tended to get left behind. Until relatively recently, being left-handed was stigmatized, sometimes as an abnormality or sign of weakness. Left-handed children were forced to learn to write with their right hands, often to their significant disadvantage.
Of course, we now know that there’s nothing wrong with being left-handed. As University of Toledo psychologist Stephen Christman recently explained in Scientific American, there’s almost no evidence to suggest that lefties are at any sort of physical or psychological disadvantage. For one thing, lefties have comprised roughly 10 percent to 15 percent of the general population for many thousands of years. The fact that the trait has remained stable over many generations suggests that left-handedness is not an evolutionary weakness, as many psychologists of the past believed.
But handedness does come with specific physiological and neurological differences. Research remains incomplete, but here are some things we know about the unique cognitive and psychological profiles of the left-handed:
They may be quicker thinkers.
Lefties may be able to use both sides of their brain more easily and efficiently.
According to an Australian study published in 2006 in the journal Neuropsychology, left-handed people tend to have faster connections between the right and left hemispheres of the brain, which leads to quicker information processing. The study authors measured participants’ performance on a task that assessed transfer time between brain hemispheres, and one that required them to use both sides of their brain at the same time.
The research revealed that left-handed participants were faster at processing information across the two sides of the brain ― a cognitive advantage that could benefit them in things like video games and sports.
They may be left-favoring in decision-making processes.
The hand you use may have a surprising effect on the way you judge abstract ideas, like value, intelligence, and honesty.
A 2009 Stanford University study found that left-handed and right-handed people may engage in an implicit favoring of their dominant side. In the study, participants viewed two columns of illustrations and were asked to judge which seemed more happy, honest, intelligent and attractive. Left-handers implicitly chose illustrations in the left column, and righties tended to select images on the right side.
"For left-handed people, implicitly, they think the good stuff is on the left and bad stuff is on the right, even though consciously, explicitly, everything in language and culture is telling them the exact opposite,” the study’s lead author, psychologist Daniel Casasanto, said in a statement.
Lefties have the upper hand in some sports.
While less than 15 percent of the general population is left-handed, 25 percent of Major League baseball players are lefties. Why? It may be because they tend to have faster reaction times, as the 2006 Australian study cited above found.
But there’s another reason. Studies have found that lefties seem to have a real advantage in interactive sports, such as boxing, fencing, tennis, and baseball ― but this advantage doesn’t extend to non-interactive sports, like gymnastics and diving. It’s possible that because of their different physical orientation and movements, lefties can throw off right-handed opponents, who are used to going up against other righties.
Their brains may organize emotion differently.
Your dominant hand may determine how emotions are arranged in your brain. A 2012 study published in the journal PLoS ONE found that in left-handers, motivation was associated with higher activity in the right hemisphere of the brain, while the opposite was true of right-handers.
This may have significant implications in caring for anxiety and mood disorders, which are sometimes treated using brain stimulation to increase neural activity in the left hemisphere.
“Given what we show here, this treatment, which helps right-handers, may be detrimental to left-handers ― the exact opposite of what they need,” one of the study’s authors, psychologist Geoffrey Brookshire, said in a statement.
Lefties may be more creative thinkers.
Many experts and studies have suggested a link between left-handedness and creativity. Is it real? Quite possibly. Some research has found that lefties are better at divergent thinking (the ability to think of many solutions to a single problem), a cognitive hallmark of creativity. However, it’s important to note that studies show correlation, not causality, so the findings aren’t entirely conclusive.
Another possibility, proposed by University College London psychologist Chris McManus in his book Right-Hand, Left-Hand, is that the brains of lefties have a more highly developed right hemisphere, which has been suggested to be more involved in creative thinking.
There’s one additional potential link between left-handedness and creativity ― one that’s speculative but still intriguing. Growing up in the left-handed minority and seeing themselves as different from their peers, some children may come to develop what’s known as an “outsider’s mindset,” or a tendency to have a self-image that’s more individualized rather than group-oriented. Such a mindset can predispose a person to develop qualities like independence and non-conformity, which psychologists have linked to creative thinking and innovation.