Yogi Berra, Larry Bird, Martina Navratilova, O.J. Simpson, Barack Obama, Oprah Winfrey, Angelina Jolie, Jerry Seinfeld, Lady Gaga and even Bart Simpson. The thread that connects this impressive list? They are all left-handed! Handedness has always intrigued scientists and parents. And to the predominantly right-handed world, there is something elegant and appealing about a left-handed athlete or musician. Are left-handers really more artistic, more athletic, and more creative than right-handers? And why are some of us left-handed in the first place?
Raise Your Better Hand
Handedness, in very basic terms, points to the hand predominantly used by a person. Researchers have multiple ways of evaluating this – the hand used for writing; the hand that performs better at a manual task; or the hand you prefer to use without considering performance speed or accuracy. It is an intriguing area because left-handers are a minority (only one in ten people are left-handed) and they often figure among the most brilliant, creative or athletic people we know.1 But left-handed people didn’t always have it easy. Historically, being left-handed was seen as an aberration, something to be fixed in a child, and even as something sinister. In the English language, too, “left-handed” is often synonymous with perverse, awkward, defective, ambiguous … you get the drift!
What Makes A Leftie?
Heredity And Genes
Handedness is determined by a mix of factors and science hasn’t yet been able to pinpoint one specific reason for it. Heredity is thought to play a part. Those who are left-handed typically have more family members who are left-handed. One study showed that while roughly 10–14% of left-handed kids have one left-handed parent, in cases where both parents are left-handed, a whopping 46% of the kids inherited this trait.2 There have been searches aplenty, but no specific “leftie” gene has been identified yet. A combination of genetic influences is considered to be the most likely reason.
Left-Handedness Starts Early
With advancements in ultrasound technology, observing the movements of a fetus can help to predict if the child will be a leftie or not. The in utero levels of testosterone are also thought to be an influencing factor. Prenatal testosterone levels, as per a Finnish study, were the only plausible explanation (though not conclusive) for why female twins in opposite-sex pair of twins tended to be right-handed.3
Leftie In A Right World
Apart from genetic factors, heredity, and even just plain chance, the environment may also play a part in determining the final preference. Till recent times, a lot of stigma was attached to a significant usage of the left hand. Many cultures and religions too label the right hand more auspicious or “proper.” This, in turn, has led to many children being forced to change their natural predilection. Even of their own accord, left-handed children are seen to change their preference, especially between the age of 2–4 years. This is when they are learning to independently attempt significant activities like eating, writing, or throwing a ball. And if 90% of the people around them are using their right hand, especially the prominent caretaker, they may just subconsciously make the switch. A study in the 80s found that about 11% of the control group felt pressurized by environmental factors to change their left-handedness and 8% succumbed to the pressure.4
What’s The Difference Between Left And Right?
So only about 10% of people are left-handed. Yet, why do we find this such a fascinating field of study? Because it gives us phenomenal insight into how the brain functions. A basic understanding of the brain is that the left hemisphere controls the right side of the body and vice versa – that is, brain lateralization. The left hemisphere (right-hand prominence) controls language, speech, and logic and is called the linear thinking mode. The right hemisphere controls creativity, perception, and art and is called the holistic thinking mode. This has given birth to generalizations like left-handers are more creative or are better musicians and sportspersons while right-handers are better writers, speakers, scientists, etc. But research doesn’t endorse any of these assumptions. The importance of handedness lies more in our understanding of the human brain and how it can help treat brain malfunctions.
Yet, while handedness may not be predictive about what a person does well, it may be an indicator of how they will behave.
- Divergent thinking: Some research does show that lefties are better at divergent thinking, a method of idea generation that explores many possible solutions.5
- Negative thinking: Multiple studies suggest that lefties are more prone to negative thoughts, phobias, post-traumatic stress disorder, and moodiness.6 This is in line with the concept of emotional lateralization, with the right hemisphere of the brain thought to control more of our emotional functioning.7
- Listening differently: The right brain, and hence lefties, hear slow-changing sounds like syllables better while righties prefer faster changing sounds like consonants. So the way a left-hander and right-hander hear the same speech will be different. And this is important information that can come in handy in the treatment of language or speech disorders, and even a stroke.8
Left Or Right
Research may indicate some variations in how a left-hander and right-hander may act or behave. But these studies are of more value in medical terms, helping to better understand the brain and treat it. As for all the stories about how great a left-handed athlete or artist is, remember that, statistically, for every one such athlete or artist, you are likely to find nine equally good right-handed ones! So take the hand you are born with and make the most of it!
|↑1||Coren, Stanley. The left-hander syndrome: The causes and consequences of left-handedness. Simon and Schuster, 2012.|
|↑2||Chamberlain, Herbert D. “The inheritance of left-handedness.” Journal of Heredity (1928).|
|↑3||Vuoksimaa, Eero, CJ Peter Eriksson, Lea Pulkkinen, Richard J. Rose, and Jaakko Kaprio. “Decreased prevalence of left-handedness among females with male co-twins: Evidence suggesting prenatal testosterone transfer in humans?.” Psychoneuroendocrinology 35, no. 10 (2010): 1462-1472.|
|↑4||Porac, Clare, Stanley Coren, and Alan Searleman. “Environmental factors in hand preference formation: Evidence from attempts to switch the preferred hand.” Behavior genetics 16, no. 2 (1986): 251-261.|
|↑5||Coren, Stanley. “Differences in divergent thinking as a function of handedness and sex.” The American journal of psychology (1995): 311-325.|
|↑6||Chemtob, Claude M., George C. Curtis, Wiecher Van Houten, and Jeffrey Guss. “Familial and personal handedness in phobic anxiety disorder.” The Journal of nervous and mental disease 190, no. 4 (2002): 267-270.|
|↑7||Heller, Wendy. “Neuropsychological mechanisms of individual differences in emotion, personality, and arousal.” Neuropsychology 7, no. 4 (1993): 476.|
|↑8||NEW STUDY: HOW PEOPLE MOVE AFFECTS THEIR HEARING, Georgetown University.|