Being able to use both hands equally well is a rare and intriguing ability. Ambidexterity, or being “ambidextrous,” means being able to use the right and left hands with equal ease for everyday tasks like writing, throwing, and brushing your teeth. While some people train themselves to become ambidextrous later in life, research shows that natural ambidexterity is something people are generally born with.
What does it mean to be ambidextrous?
Ambidexterity refers to the ability to use both the left and right hand equally well. True ambidexterity is quite rare – only about 1% of the population is estimated to be fully ambidextrous.
More commonly, people have a dominant hand that they favor for detailed tasks like writing or drawing, and a non-dominant hand that can do other things pretty well, like throwing a ball or cutting with scissors. This is called cross-dominance or mixed-handedness.
Someone who is truly ambidextrous has no strong hand dominance. They can perform tasks equally well with either hand. Ambidextrous people can write, draw, brush their teeth, use tools, and throw a ball with both hands interchangeably.
Signs of ambidexterity
Here are some signs that someone may be naturally ambidextrous:
– They write, draw, eat, and brush their teeth with equal ease using either hand.
– They frequently switch hands for tasks without thinking about it.
– They can throw a ball powerfully and accurately with both hands.
– Using scissors, knives, and other tools feels equally comfortable in either hand.
– One hand does not feel noticeably stronger or more coordinated than the other.
– As a child, they did not have a clear hand preference for activities like coloring or building blocks.
Is ambidexterity genetic?
Research strongly indicates there is a genetic component to being ambidextrous. Ambidexterity seems to run in families, suggesting it is passed down genetically in many cases.
Studies of twins provide some of the best evidence that ambidexterity has genetic origins. Identical twins have identical DNA, while fraternal twins share only 50% of their DNA on average. Research shows that if one identical twin is ambidextrous, the other one almost always is too. But ambidexterity in one fraternal twin does not necessarily mean the other will also be ambidextrous.
Based on twin studies, scientists estimate that genes contribute about 25% of the likelihood someone will become ambidextrous. The other 75% of the variability in hand preference and coordination is shaped by environmental and other biological factors.
While specific “ambidexterity genes” have not been definitively identified yet, people who are naturally ambidextrous likely have particular genetic variations that affect brain hemisphere dominance and hand control.
Evidence from brain imaging
Brain imaging studies also demonstrate key differences in the brains of ambidextrous people compared to right-handers and left-handers.
In right-handed people, the left hemisphere of the brain typically dominates and controls the right side of the body, including the right hand. The opposite is true for lefties.
But in ambidextrous individuals, neither brain hemisphere takes charge. Brain activation is more evenly balanced between the two sides.
Areas of the motor cortex that control hand movement and areas like the corpus callosum that enable inter-hemispheric communication tend to be more symmetrical and balanced in the brains of the ambidextrous.
Is ambidexterity present from birth?
The vast majority of research indicates that natural ambidexterity emerges very early in life and is present from birth. Infants and young toddlers who go on to be ambidextrous show no hand dominance or preference very early on.
Here is some evidence that ambidexterity develops before birth or in infancy:
– One study found that ambidextrous fetuses moved their left and right hands equally often in the womb during the third trimester.
– Another study showed that newborn babies who became ambidextrous did not favor one hand over the other for grasping objects.
– Infants who later became ambidextrous showed no difference in hand performance for a skilled task like rotating a curved tube to retrieve a toy.
– Observations of hand preference during activities like reaching for objects, pointing, and grasping show no clear dominance pattern among toddlers who are ambidextrous.
– No clear hand preference emerges over time for children who go on to be ambidextrous. They stay neutral unlike other kids who develop a dominant hand.
This data indicates that the neurological wiring and hand capabilities that enable ambidexterity are present at birth or develop so early in infancy that no hand preference has yet emerged.
No hand retraining needed
Ambidextrous children do not need any special training to use both hands equally well. They spontaneously begin using both hands for tasks as soon as their fine motor skills develop enough to allow complex hand coordination.
In contrast, adults who train themselves to become ambidextrous have to put conscious effort into strengthening their non-dominant hand through extensive practice. Natural childhood ambidexterity does not require forcing the use of the weaker hand.
Why is ambidexterity so rare?
If ambidexterity is influenced by genetics and present from birth, why is it so uncommon, affecting only about 1% of people? There are a few reasons why natural ambidexterity is hard to come by:
– Genes linked to ambidexterity are likely very rare in the gene pool. Two parents carrying ambidexterity genes would have to pass them on for a child to develop the trait.
– Even with the right genes, the wiring and capabilities of both brain hemispheres have to develop with very precise symmetry in utero for perfect ambidexterity to emerge. Any imbalance disrupts this.
– After birth, most infants receive greater stimulation and practice on one side of their body that reinforces hand dominance. For instance, caregivers may unconsciously cradle them more often on one side.
– Societal tools and writing conventions favor right-handedness, which can override early ambidexterity.
So ambidexterity is uncommon because it relies on a rare genetic blueprint, precisely balanced brain development, and an environment that does not interfere with or override natural hand use tendencies.
Left-handedness is more common
While full ambidexterity is very rare, left-handedness is relatively common, affecting 10-13% of people. This is because becoming left-handed only requires dominance by one brain hemisphere (the right side), rather than equal brain activation on both sides.
Left-handedness has also become more socially acceptable over time, allowing more children to develop and maintain left hand dominance. Legal and cultural suppression of left-handedness in the past often overrode people’s natural laterality.
Can ambidexterity be learned?
It is very difficult for someone right or left hand dominant to become fully ambidextrous later in life. However, you can train yourself to use your non-dominant hand more proficiently through extensive practice and repetition.
For example, left-handed people can teach themselves to write legibly and do other fine motor tasks with their right hand. Righties can force themselves to use left-handed tools or throw a ball with their left hand.
But this learned ambidexterity requires great effort and conscious attention. The non-dominant hand rarely achieves the fluidity and precision of the dominant hand. And the ability to use both hands interchangeably for complex tasks is limited.
Here are some tips for improving your non-dominant hand:
– Start by practicing simple tasks like brushing your teeth or using a spoon.
– Move on to manipulating objects like blocks or clay to build hand coordination.
– Work on catching and throwing a ball with your non-dominant hand.
– Practice handwriting skills and tracing letters.
– Use your computer mouse or toothbrush with the weaker hand.
– Challenge yourself with progressively more difficult tasks like drawing, needlework, or shuffling cards.
With regular practice for a few months, most people can attain decent functioning in their non-dominant hand, even if it never matches their innate handedness.
Kids versus adults
Younger children generally have an easier time learning new hand skills compared to teens and adults. Their developing brains retain more neuroplasticity or ability to rewire neural connections.
Adults attempting to train their non-dominant hand often hit plateaus in performance due to ingrained hand preference pathways. But kids can progress more rapidly from novice to proficient performance.
Still, it takes considerable time and effort for children to attain high-level ambidexterity if they are naturally right or left handed. It does not come close to the innate fluidity of using both hands seen in natural ambidexterity.
Benefits of ambidexterity
While very uncommon, being ambidextrous does come with some advantages:
– **Enhanced multitasking** – Ambidextrous people can perform some manual tasks simultaneously like writing while brushing their teeth.
– **Faster reactions** – They can catch or deflect balls more quickly by always using their closest hand.
– **Reduced injury impact** – An injury to one hand does not take away their manual abilities since the other hand works just as well.
– **Creative problem-solving** – They can take a creative approach using either hand for tasks, crafts, or art.
– **Brain benefits** – Some research links ambidexterity to benefits like enhanced creativity, cognitive flexibility, and problem-solving.
However, these benefits have to be weighed against the challenges ambidextrous people face in a world designed for right-handers. They have to adapt to use tools and products designed for the right hand. And they often have to deal with skepticism or social pressure to conform to right-handedness.
Exceptional multitaskers
One key benefit of being ambidextrous is having exceptional multitasking abilities. Ambidextrous people can perform some manual tasks simultaneously since hand coordination and brain control is evenly split.
For example, natural ambidextrous writers can print legibly with one hand while simultaneously printing or sketching something else with the other hand. They can also print two different things at the same time.
This ability to multitask with both hands gives ambidextrous people a unique edge for juggling manual tasks efficiently.
Famous ambidextrous people
While clearly in the minority, ambidexterity has been common enough throughout history that many famous figures are believed to have been naturally ambidextrous. Here are a few notable likely ambidextrous people:
– **Leonardo da Vinci** – The quintessential Renaissance man was said to be able to write forward with one hand while writing backward with the other.
– **Michelangelo** – The artistic legend could apparently paint with either hand.
– **Lewis Carroll** – The Alice in Wonderland author was able to simultaneously write with one hand while mirror writing with the other.
– **Babe Ruth** – Baseball’s famous slugger batted and threw right-handed but performed most other tasks left-handed.
– **Paul McCartney** – The Beatles musician can play guitar, bass, and piano equally well using either hand.
– **Benjamin Franklin** – America’s Founding Father taught himself to write with both hands in order to save time.
– **Mark Twain** – The author of Tom Sawyer could write a different sentence with each hand at the same time.
– **Billy Bryan** – The famous trial lawyer was known for taking notes with one hand while writing with the other.
– **Timothy Dexter** – The 18th century businessman wrote two books simultaneously using both hands.
– **IIIyy Alexander** – The iconic ballet dancer could perform complex sequences with either the right or left hand leading interchangeably.
Conclusion
In summary, ambidexterity is a rare and intriguing ability to use both hands equally well that likely originates from birth due to genetic factors. Research shows ambidextrous people have balanced brain activation and hand coordination from very early childhood on.
While ambidexterity can be learned to some degree, true natural ambidexterity is challenging if not impossible to attain later in life after hand dominance is established. But the effort can help enhance skills in the non-dominant hand.
Ambidexterity’s rarity comes from needing very specific genetic and developmental circumstances. But the ability offers some advantages like creative problem solving, multitasking skills, and overcoming handedness constraints. And famous ambidextrous figures help reveal the hidden potential in being able to use both hands interchangeably.