Do Ambidextrous People Really Exist? Hand Dominance and Skills

As soon as dexterity becomes a demand, infants will exhibit a hand preference. Such tasks will include writing, drawing or placing pins into holes. Highly skilled tasks requiring control and dexterity will require a highly specialized cluster of cells in the brain to oversee this function.

Handwriting Specializing Skills

Study into Being Ambidextrous

During my tine teaching art, I conducted research into drawing ability and handedness and found no real correlation between drawing ability and handedness. Those who had difficulty drawing were more often found in people who performed tasks with almost equal demand on both sides of the body. Examples are the preferred leg to kick a ball, eye to peek through a telescope, and so forth. This is known as low lateralization. This is not the same as being ambidextrous, as the subject still has a dominant hand to write with.

Does Ambidextrous Really Exist?

People who exhibit low lateralization in brain function I find were also more likely to have directional confusion (between left and right) as well as difficulty in reading an analogue clock and to suffer dyslexia. Difficulty in drawing, it would seem, also became problem within this group (although not all). This confusion could be said to be reflected within the term ‘ambidextrous’, as ambi comes from the Latin word to mean ‘both’ and dexter, means ‘right’. Translated, it would mean ‘both right’.

Ability in Handedness

Yet those who exhibited high lateralization more often have good hand-to-eye coordination and suffered less from the aforementioned problems. Which brings me to the question: what makes someone ambidextrous?

I have little or no hand preference when it comes to scraping the wallpaper, sweeping the floors or scrubbing. This doesn’t mean I am ambidextrous. Michelangelo when painting the Sistine Chapel ceiling on his back swapped hands when one arm became tired and but could still paint with great skill with his right hand (he was left handed). When under duress, such as environmental influences or injury, the non preferred hand or limb can be called upon to do tasks almost as well. This also does not make the person ambidextrous genetically.

Ambidexterity Ability

The more specialized the task, the more a hand preference will be exhibited. Again this reflects on the highly specialized cells in the brain that controls the task. A specialized skill is not the same as applying strength or repeating an action. In fact, it goes further than just dexterity, as the left handed guitarist will fret with the right hand (a skillful task) whilst the other hand will strum or fingerpick.

The Dominant Hand and the Non Dominant Hand

The ‘leading’ hand is the one that can do tasks with supreme accuracy, control and pressure application with small differences with nimbleness and precision. The dominant hand in the case of the guitarist or cellist will be the one to pluck, strum, bow or fingerpick. Perhaps the ultimate in controlling pressure and direction with precision is performing brain surgery.

Specialized Cells in the Brain

So why would a task of such skill exhibit a hand preference? The answer is because this reflects the specialism of the cells within the brain that controls these tasks. These cells have been found to be concentrated and therefore located in one place. But where? The answer would be either the left side or the right side of the brain. There is little point in duplicating these cells in both sides, as this would make the brain less efficient. A hand preference would therefore reflect the fact the brain cells controlling the function will be in one side or the other.

Lateralization in Tasks

High lateralization in task performance is not so evident in animals as in man. It would seem we have evolved specialized skills over millions of years, perform speech, arithmetic and tool making. These demands would similarly evolve brain cells that would make these tasks possible (and to be located on a particular site in the brain). Take the example of Broca’s Area, the cells that control speech, located (mostly) only in the left side of the brain. Millions of years ago, these cells would have been less distinct before slowly coming together like the formation of galaxies.

Hand Preference and Handedness

So if someone tells you he/she is ambidextrous, to what extent? Tasks requiring little or no demand upon hand control and precision will have little or no hand preference. Injury and environmental factors will create the misleading impression the person is ambidextrous. Highly skilled tasks are more likely to exhibit a preference. Let’s take some examples of such tasks.

Tasks of low skill (little or no hand-preference)

Watering the plants, holding a cup of tea, scraping wallpaper, dusting, cleaning.

Tasks of medium skill (some hand preference will be evident)

Combing hair, shaving, painting windowsills.

Tasks requiring great precision in pressure application and directional control (hand preference most likely)

Putting a ball in golf or snooker, drawing, writing, applying makeup, painting a portrait and, of course, writing.

Handedness of Brain Surgeons

In conclusion, I don’t mind an ambidextrous person making me a cup of tea but not to perform cosmetic surgery.

Dexterity and Handedness

The higher the demand upon dexterity, pressure control and skill, the more likely the hand preference will be shown. I can write with both hands but my handwriting will be scruffy and take longer with my right hand. Some people may have the ability to write neatly quite quickly with both hands, but requires practice. My personal belief is that there is always a preference in hand, no matter how small, particularly in performing specialized tasks.