What You Should Know About Left-Handedness
On account of International Left-Handers Day learn more about left-handedness, beyond the veil of bias and stigma.
According to 2019 estimates, approximately 10% of the global population is left-handed, which equates to roughly 700 million people including myself. Yet, we live in a world designed for the other 90%. Growing up as a left-hander, I still struggle to use everyday objects like scissors or write properly in a notebook without getting ink all over my hands, let alone use a ruler to measure anything. I also find it incredibly amusing how there is an unsaid rule about right-handedness being the correct way. These factors frequently made me wonder why this was the case, and why there are such few people left-handed.
In honour of International Left-Handers Day (celebrated on August 13), I thought I'd share some of the research I came across to provide you with insight into left-handedness and to help alleviate the cultural stigma associated with being left-handed.
This article will look at handedness, the history of left-handedness, factors that influence left-handedness, and the benefits of being left-handed.
Shortcuts For The Busy Reader
What Is Handedness?
The American Psychological Association describes handedness as the repeated use of one hand over the other when performing certain tasks. Those who are left-handed subjectively prefer using their left hand to carry out multiple tasks while those who are right-handed prefer to use their right hand for the same.
The Journey of Left-handedness Through Time
Throughout history, left-handers have been subjected to sociocultural bias. The word “left” in fact, comes from the Anglo-Saxon word “lyft” which means weak; while its antonym “right” comes from the word “riht” which means straight, or not crooked. Even on a daily basis, we use the term "right" interchangeably with the terms "correct" or "good," as in upright, "doing the right thing," righteous, and so on. However, this is not the case with the word "left."
This is also noticeable in other languages. In French, the left is referred to as “gauche” (awkward), while the right is “droit” (correct), and in Italian, the left is referred to as “sinistra” (derived from the Latin word sinister, which in English means evil). The negative connotations of the word "left" across languages can highlight how people inherently associate the term with something incorrect or negative.
Being left-handed was also associated with practising witchcraft and devil worship, in the Middle Ages, further perpetuating the stigma against them. This stigma persisted even during the Victorian Era, which witnessed a sudden decline in left-handers. This was not due to fewer left-handed children being born, but rather to avoid any social stigmas and pressures, many of them chose to use their right hands to carry out work. These effects were exacerbated further by the Industrial Revolution which brought in machinery that was designed for right-handers, forcing many left-handers to switch in order to use the machinery.
In the early 20th Century, studies highlight accounts of British and American teachers attempting to force students to use their right hand instead of their left. This is because they viewed using one’s left hand to carry out tasks as an act of defiance and would resort to torturous methods such as restraining a child’s left hand to get them to use their right hand.
While you might think that these practices are a thing of the past, this is not the case. Being left-handed is still frowned upon in many Asian and African societies and is associated with being dirty and impolite. Due to cultural and religious practices, left-handers from these countries often face stigma and discrimination and, in some cases, are forced to switch hands.
Having said this, it should be noted that left-handedness is not a condition that can be treated; rather, it is influenced by a variety of factors, which we will investigate further below.
What Influences Left-handedness?
Over the years, researchers have been interested in the topic of handedness. We previously mentioned that having a dominant hand is a subjective feeling. While researchers have yet to reach a conclusion about why some people are left-handed, studies show that it is more than just a subjective feeling.
Genetics is one factor that plays an important role in influencing our handedness. Previously, it was assumed that an individual’s handedness was determined by only one gene. Recent research, however, has shown that up to 40 genes contribute to this trait. While each gene may not have a strong enough effect on its own, together, they can influence an individual's handedness.
Aside from genetics, brain asymmetry is another major aspect that influences our handedness. The cerebrum is the largest part of the brain and is divided into two hemispheres. When it comes to movement, each hemisphere has a region known as the motor cortex. When it comes to tasks like grasping, drawing and so on, left-handers demonstrate to have a more dominant right motor cortex which controls the left side of our body.
A recent brain mapping study also supports the concept of brain asymmetry. The findings suggest that left-handers have thicker brain areas such as the postcentral gyrus and inferior occipital gyrus are thicker amongst left-handers. These regions are associated with hand and finger movement, which adds to the explanation for left-handedness.
It should be noted that while these factors do provide possible explanations for why one tends to be left-handed, none of them provides a definitive answer as of yet. They all suggest that certain differences can be attributed to the development of this trait. Having said that, let us understand if this difference accounts for some advantages for left-handers.
What Are the Benefits of Being Left-handed?
Literature on handedness is continually expanding, with some suggesting that being left-handed has an inherent advantage.
According to some studies, left-handers have a thicker corpus callosum (nerve fibres that connects the two cerebral hemispheres). This promotes greater connectivity between both hemispheres which is linked with aspects such as language fluency and memory retention.
Left-handed pianists are faster and more accurate when playing reversed melodies. Having practised the piano for a short while, this is key. According to the study, left-handers are able to adapt better when it comes to tasks that require spatial(visualisation) or motor (movement) attention allowing them to play more accurately.
Last but not least, those who are left-handed may benefit from being better at sports. An examination of the top 100 players in interactive, time-pressure sports such as cricket, baseball, and table tennis between 2009 and 2014 revealed that 30% of the best athletes were left-handed. Dr Florian Loffing who conducted the study suggested two reasons for this. The first is because left-handers could be better at tasks that involve spatial visualisation and movement.
Secondly, he suggested that the left dominance in these sports could be due to the rarity of the left-handers. As a result, their opponents will not be familiar with the strategies and movements employed by left-handed athletes, thereby allowing them to use their strategies to their advantage.
Our handedness, whether right or left, plays an important role in our daily lives. However, using one's right hand became the norm over time, while left-handers, who were a minority, faced social and cultural stigma. The findings of this study aid in identifying the biological and neural mechanisms underlying left-handedness, indicating that it is a natural phenomenon. They also identify specific advantages that left-handers have in specific domains. With the research presented above, we can dismiss societal perceptions of left-handedness as impure, evil, or dirty. Finally, regardless of what being left-handed means in your culture, it is critical that we do not find another reason to discriminate among ourselves in an already divided world.
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