The notion that lefties are smarter than righties has been floating around for some time.
Here’s what the research says when it comes to lefties and IQ.
Left-handed people, also known as “lefties” and “southpaws,” make up about 10 percent of the population.
Historically, left-handed people have been viewed and treated as outcasts. In the Middle Ages, left-handed people feared being accused of witchcraft.
As recently as the early 20th century, many educators in the United States forced left-handers to “retrain” their natural tendencies in order to become right-handed.
Scientists also used to think that left-handedness was due to minor brain damage in early development.
These myths have been debunked over the years, and some have asserted that being left-handed is actually associated with higher intelligence.
While the claim is intriguing, medical literature reveals inconclusive results.
The belief that handedness is associated with intelligence has been around for centuries.
Research seems to support both sides of the argument. Here’s what studies have shown in favor and against the idea that left-handedness has anything to do with intelligence.
Are right-handed people smarter?
A 2010 study in the Journal of the International Neuropsychological Society revealed that strong right-handers seemed to perform slightly better on cognitive tests when compared to left-handers.
A 2015 study in Neuroscience & Biobehavioral Reviews looked at five meta-analyses that included data on more than 16,000 individuals. They found no difference in IQ levels among left- and right-handed people, but left-handers appeared to be more likely to have an intellectual disability.
However, this study indicated that people who were intellectually gifted or following typical development were also just as likely to be left-handed.
A study in
Although data suggested that right-handed people had slightly higher IQ scores compared to left-handers, the scientists noted that intelligence differences between right and left-handed people were negligible overall.
Are left-handed people smarter?
Other studies have found lefties seem to have the upper hand when it comes to smarts.
A 2007 study in the Journal of the Indian Academy of Applied Psychology found that, out of 150 subjects, left-handed participants were significantly more likely to perform better on an intelligence test than right-handed people. Right-handers also took more time to complete the test.
Examining data on about 400,000 people, scientists discovered that the left and right hemispheres of the brain were better connected and more coordinated in regions involving language in left-handed people.
These traits suggest that left-handed individuals may have superior verbal skills.
Handedness, or hand preference, is the tendency to be more comfortable and skilled when using one hand over the other to perform tasks.
While right-handedness and left-handedness are well-known, there are also some less common variations, including:
- Mixed-handedness: favor different hands depending on the task
- Ambidextrousness: can perform tasks equally with either hand
Influences on handedness
Scientists believe your hand preference is a complex characteristic that’s influenced by many factors, including:
- random chance
Hand preference develops before birth and becomes more obvious during early childhood and throughout one’s life.
Researchers believe hand preference may have to do with the developmental differences between the right and left hemispheres of the brain. The right hemisphere controls movement on the left side of the body, while the left hemisphere controls movement on the right side of the body.
Recent studies have also suggested that multiple genes, maybe even close to 40, are related to hand preference.
Children of left-handed parents are more likely to be left-handed than children of right-handed parents. But because lefties are comparatively rare, most children of left-handed parents are right-handed.
Cultural influences, environment, and prenatal exposures may also play a role in determining handedness.
Intelligence can be defined in many different ways.
In psychology, for instance, intelligence may be described as possessing one or a combination of the following attributes:
- a higher ability level, such as abstract reasoning, problem-solving, or decision-making
- ability to learn
- emotional knowledge
There are different theories of intelligence and ways to measure it, including the well-known intelligence quotient (IQ) tests.
While certain exams can provide useful information, they aren’t the only way to assess intelligence or validate this complex label.
Some research has shown lefties may be more likely to develop certain conditions, including:
- Parkinson’s disease
breast cancer post-traumatic stress disorder (PTSD)
- learning disabilities, such as dyslexia
But other studies reveal lefties might have the advantage in certain areas.
An older article in the American Journal of Psychology suggests that left-handed people may be better at divergent thinking, a thought process used to generate creative ideas.
Hand preference is highly subjective and personal. Most people determine their handedness during childhood, sometimes with the help of a parent or caregiver.
But if you’re not sure if you’re a leftie or a righty, ask yourself this question: Which hand do you perform most activities with, not just writing?
If you happen to use one hand for about half of the activities and the other for the other half, you may be mixed-handed.
While there are curious differences between lefties and righties, a higher intelligence level probably isn’t one of them.
Many studies show mixed results when examining this complicated link, leading researchers to conclude that left-handed people are no smarter than their right-handed counterparts.