What percentage of lefthanders are autistic?

What percentage of lefthanders are autistic?

If asked «what was the first thing that impressed you about Sri Lanka» I would have to say «the extraordinary large number of left-handed people». In western culture left-handedness has been held in contempt, in spite of evidence of superior intellectual capacity. In Britain such people are referred to as ‘cack-handers’ (from the Teutonic word for excrement). In Ireland we are ‘ciotógs’. Right-handed people are dextrous, while left-handers are sinistral and sinister means strange. In France we would be gauche, which word carries over into English as socially awkward. This led me to wonder whether there was a link with autism and indeed, there is a statistically greater number of left-handers amongst autistic people.

Personal experience suggests that there is a link with certain subject specialisms. As an undergraduate attending the nuclear physics lectures of Ireland’s Nobel laureate, Ernest Walton, I noted that 60% of the class were left-handed. Several years later, as a postgraduate I was invigilating in a hall where there were 180 aspiring teachers doing a Diploma in Education examination. Only one of these was left-handed. Was this significant? Did it mean that teachers are antagonistic to left-handedness? Certainly, in my school days my teachers did try to change me. They eventually gave up.

The Chinese consider that left-handed people are very clever and here there is a problem. You do not see many people writing with their left hand in China. Parents of young children are very worried. What if they were left-handed, but not very intelligent? Would this be a disgrace to the family? So, children are forced to write with their right hand. So, how do I know that there are left-handed people in China?

imple. Their parents were working so hard to change writing habits that they forgot to tell them that they should also hold their chop-sticks with their right hand. When I taught at the NCUK college in Shanghai all the teachers would go out for lunch together. So here we had an interesting case where all the lefties amongst the staff had to sit next to each other. Have you ever tried using chopsticks while sitting next to a left-hander doing the same thing? And so, the ever curious scientist wonders whether left-handers tend to sit next to each other. At meetings I map the laterality of those sitting around me and then try to see if it is statistically significant. However, just as with Schrödinger’s cat, the very fact that I have told you about this will ruin any future experiments.

My son is left-handed and I believe that I know why. I simply put his Fisher-Price Activity Centre on the left side of his cot. My wife was not willing for us to have a really large family so that I could exhaustively test this hypothesis. I wonder why? Which brings back the questions: Why are so many people in Sri Lanka left-handed? Does this have an influence on the career paths that our young will take? — Warren Dalton

Raising a Left-Handed Child

Eleven percent of the population is born left-handed, and if they seem different, it’s because they are! Learn six tips for raising a left-handed child.

Step 1: Is she a lefty? Congratulate—or blame—yourself.

The question of whether left-handedness could be inherited was answered in 2007 when scientist Clyde Francks announced the isolation of a gene—called LRRTM1—that contributes to left-handedness. Francks’ research suggests the gene is inherited on the father’s side.

Parents can monitor their child’s handedness by keeping tabs on which hand reaches for toys and food or by noting which direction a child stirs with a spoon. Righties tend to stir clockwise, while lefties stir counterclockwise.

Babies usually start showing a hand preference at about 7 to 9 months old, but they may not make a final distinction until they start school. «Doodling and eating are not fine motor skills requiring premium dexterity, which is why many babies and toddlers, under the influence of rapidly developing brains, switch between using the left and right hands, often masking underlying handedness and leading parents to conclude falsely that their children are ambidextrous,» David Wolman writes in A Left-Hand Turn Around the World. «This is a common error among people who associate ambidextrousness with high intellect.»

Step 2: Remember that she is different.

Lefties think differently. The left side of the brain—which controls the right hand—is in charge of speech, language, writing, logic, math and science. The right side—which controls the left hand—is responsible for music, art, perception and emotion. The right side handles abstract, big picture ideas; the left side thinks in straight lines.

Right-handers’ brain organization is usually quite rigid. The right side only handles language and logic; the left side only handles emotion and perception.

Meanwhile, left-handers’ brains tend to be more flexible—understanding of music could be on the left side or math could be on the right. As a result, the corpus callosum, the part of the brain that allows the two hemispheres of the brain to communicate with each other, can be 11 percent larger in left-handed brains than right-handed ones.

Some think left-handers’ brain structures may be the product of living in a right-handed world. «Growing up surrounded by right-handed equipment, instruments, appliances and tools, lefties give their nondominant side more exercise than the average righty,» Melissa Roth wrote in The Left Stuff. «Biomechanic research has revealed that training the nondominant side of the body actually enhances the dominant side—something known as the cross-training effect—since the body’s neural network is integrated on both sides.»

Step 3: Get her public speaking lessons.

After all, she’s going to need to be a good speaker when she’s president.

Four of the past seven presidents have been certifiably left-handed. A fifth, Ronald Reagan, was rumored to be ambidextrous. Many people assume this means the Gipper was born a lefty, but was forced to switch by schoolteachers—a common practice all over the world until the late 20th century.

And it’s not only the presidential election winners who are left-handed. Both candidates in 2008—Barack Obama and John McCain—write with their left hands. In 1992, the left-handed Ross Perot mounted one of the strongest third-party presidential campaigns in American history against his fellow southpaws George H.W. Bush and Bill Clinton.

Is this just some fluke? According to economist and co-author of the best-selling book Freakonomics, Steven Levitt, it probably isn’t. «Ten to 15 percent of men are left handed,» he wrote in his blog for The New York Times, «which means, according to my calculations, that this many recent left-handed presidents would only happen by chance one time in 1,000.»

Step 4: Buy school and art supplies.

Some of the greatest artists in history have been lefties, including M.C. Escher, Leonardo da Vinci, Michelangelo and Rembrandt. Contrary to some reports, Pablo Picasso wasn’t left-handed—despite this handicap, he turned out to be a pretty talented artist anyway.

Painting isn’t the only profession that favors lefties. Studies have shown large numbers of left-handed students and professors in schools of architecture, music and math.

However, this doesn’t mean that all creative subjects are easy for left-handed children. Using equipment designed for right-handers can end in frustration. Prevent the problems by investing in good left-handed scissors and smudge-free pencils and pens. Parents also can relatively easily switch the settings on computers to make a mouse or cursor more lefty-friendly.

Step 5: Buy sports equipment.

Polo and field hockey are probably out of the question since both require participants to play right-handed, but many of other sports actually allow significant advantages for lefties. Left-handed fencers routinely win medals in top competitions. Left-handed boxers pose serious problems for their opponents. And playing tennis left-handed has not hampered the careers of superstars like John McEnroe, Martina Navratilova or Rafael Nadal.

In baseball, left-handed pitchers have been highly sought after since the sport’s earliest days. Since most pitchers are right-handed, batters tend to have trouble clearly seeing a ball thrown by a lefty. The advantage for left-handed pitchers is even more pronounced against left-handed batters. In the 1980s, baseball managers began capitalizing on that dominance by relying on the «left-handed specialist»—a left-handed pitcher who comes into the game to face just one left-handed batter in late innings. The left-handed specialist’s average workday could consist of as throwing as few as a five or six pitches—and then hitting the shower before breaking a sweat.

One of the greatest left-handed specialists in baseball history was Jesse Orosco, who played for nine teams in 24 seasons. When he retired in 2003 at age 46, Orosco had set the record for most ever games played by a pitcher at 1,252. He also earned around $1 million a year starting in 1988—not bad for a few minutes of work a day.

Step 6: Pay for the school supplies and sports equipment you just bought.

If you need a loan to pay for those expensive new school supplies and sports equipment, start with your left-handed relatives—they might have some extra cash lying around.

Economists at Johns Hopkins and Lafayette College investigated whether handedness affects earnings, with expectation that if it did, it would not turn out well for the lefties. «If left-handedness is associated with poorer health, higher accident rates and lower average cognitive skills, it is natural to expect that these result in lower labor productivity and thereby lower earnings,» they wrote. «Left-handed people may be less productive in those occupations which use tools, machines and systems that are designed for right-handers.» Somewhat surprisingly, they found that lefties with college educations earned 15 percent more than their fellow right-handed alumni.

On the other hand, the news isn’t all good. This left-handed wage boost did not exist for left-handed women. A different study by economists at University College Dublin and University of Warwick found that left-handed women born in 1958 actually earned 5 percent less than right-handed women.

What about teaching them to tie their shoes? Share your tips for raising a left-handed child in the comments section below.

What percentage of lefthanders are autistic?

It is sometimes said that certain mood disorders and learning difficulties are more common in people who favor their left hand. Researchers have not yet found a genetic link between dyslexia and handedness and individuals with dyslexia, a learning difficulty that affects reading, writing and spelling abilities, are split 50:50 between right and left-handedness.

However, there are fewer left-handed people in the world. In fact, the difference is 90:10. This means that dyslexia may be more commonly found in left-handed people but the relationship is not necessarily causal. There is also the question of whether or not it is more common in boys than girls.

Some evidence suggests dyslexia is just as prevalent in girls as boys but not as well recognized, while other studies (Quinn & Wagner 2015) have found reading difficulties occur more often in male individuals.

left-handed and 1% is mixed-handed or ambidextrous, which is when a person chooses to use their right or left hand depending on the task.

Though there are other species that show handedness preferences, such as chimpanzees, they tend to be split 50:50 in choosing their right or left hand. This makes explaining the right hand bias in humans a challenge for researchers studying its genetic origins.

Handedness is not a simple case of recessive vs. dominant traits. Mutations across multiple genes contribute to whether or not a person chooses to use their right or left hand more often. Recent research has revealed that the same genes implicated in handedness control the positioning of organs in the body.

Handedness may also be related to asymmetry, with the parts that control language commonly found on the left-side of the brain. To some extent there is also a question of nature vs. nurture, as not all identical twins share handedness and studies have indicated that low birth weight and mothers who are stressed while pregnant can make it more likely that children will be left-handed.

Given they were in the minority, left-handed people were historically treated as different. The left hand was considered dirty and sometimes associated with the devil. Today, in some cultures it is still forbidden to use the left hand for certain tasks, such as ritual prayer or eating.

And while educators in the US and UK no longer force left-handed children to learn how to write using their right hand, kids still require different desks, special scissors and instruction in how to place their paper to avoid smudging ink.

What is dyslexia?

Dyslexia is a brain-based learning difficulty that affects up to 10% of people in the world. It has nothing to do with intelligence and people who have dyslexia are not lazy, they simply process information in a different way. Dyslexia can vary in its severity and no two individuals will experience the same set of symptoms.

Nonetheless, most dyslexic people struggle with splitting words into their component sounds. Problems with phonemic awareness can make it difficult to spell and decode words, a crucial step in early reading skills development.

Some people with dyslexia also have difficulty interpreting visual information and identifying spatial and right-left relationships.

high frequency words are recognized by sight during reading, it enhances reading comprehension and eliminates the need for children to sound them out. The sooner dyslexia is identified, the better. This is because dyslexic children who are not taught coping skills can easily fall behind their peers in literacy skills development. They may develop negative associations with school and have low self-esteem.

If a student isn’t ready for direct intervention, they might consider Touch-type Read and Spell. It’s a typing program designed to support dyslexic children and adults by teaching touch-typing in a multi-sensory way, following a curriculum that builds phonics knowledge. Students see, hear and type a word, which reinforces it in memory and supports sight reading too.

Using a computer to touch type can also make it easier for dyslexic students to write. Information flows freely through the fingertips and onto the screen and individuals have access to spell checkers.

Do you have any experience with handedness and dyslexia to contribute? Join the discussion in the comments!

We’ve been using TTRS since my son was 10. We knew his spelling was below level and I had suspected the dyslexia, but it’s only recently that we’ve had a formal assessment. I wanted him to learn typing because he struggled with handwriting too and I knew that the sooner he learned to type, the better. I chose TTRS because of the literacy skills support.