I'm reading a book by a neurologist and piano player titled The Hand: How Its Use Shapes the Brain, Language and Human Culture. The main thesis of the book is that hand evolution and articulation are major components to the development of human language and thought. Below is a summary of Chapter 8, which is about right or left hand dominance. Get ready you left-handed geeks, (or righties) 'cause this rules.

Exactly when right or left handedness came about we don't know, but we do know that today most people are right-handed. The right/left division of our bodies mirrors the right/left division of our brains, and it’s the left side of the brain that largely controls the movements of the right side of the body and vice-versa. This has led to all sorts of theories about lefties and righties over the years, including who is more artistic, shameful, bossy, rational, emotional, etc. But if you’re like me, you might not like being put in any of those boxes. That’s why the following is so enticing.

When our ancestors came down from the trees millions of years ago, their visual systems, which predominate in the right brain, were already highly developed. That’s how it remains today. It’s possible that this left a glut of sorts on the left side of the brain, and so the ensuing hundreds of thousands of years tended to focus our fledgling skill of fine manual dexterity in the left brain, meaning right hand.

However, if you’ve ever paid careful attention to two-handed skills, you may have noticed that while your dominant hand does what we typically think of as the “skilled” work, your less-dominant hand does a whole variety of supporting tasks. In fact, the skilled movements of your dominant hand, once learned, are controlled by largely unconscious movements, while the movements of the non-dominant hand are more conscious.

A good example of this is your signature, which for most people cannot be replicated precisely when slowed down. Once you’ve memorized a task in your “muscle memory”, which is actually in your brain, the accomplishment of a skilled task is like rolling out an ordered sequence of memorized events. But what’s interesting is that this high level of skill is usually only possible in a small range of proximity (try writing your signature with your arm fully extended). Therefore, the rest of the body, and particularly the non-dominant hand, does a lot of work to orient and “deliver” the dominant hand to the task.

Think of the precision moves of athletes and pianists (or car drivers). Most of these movements do not require focused conscious attention. In fact, they happen best when we DON’T think about them.

Now, bring in the other hand (and the other side of the brain). The dominant hand is the hand in which we primarily store the recipes for these precise movements. Meanwhile, it is the non-dominant hand that constantly adjusts and orders the rest of the world so that the dominant hand can get to where it needs to be to do its highly specific work. In other words, the dominant hand is like a technician or plumber, but for this hand to do its job it needs the non-dominant hand to make dinner and drive it to work.

Writing is a good example, because while the dominant hand does all the writing, the non-dominant hand tends to spend a lot of time adjusting and orienting the paper so that the specific skill can be carried out. Pay attention the next time you write a postcard or letter.

What we’re describing is the left brain (right hand), by and large the brain of skill and rationality, being put to good use by the big-picture visuo-spatial right brain (left hand). Surely, nothing is quite as simple as this, but this explanation shatters the old convention of righties and lefties, whether that’s brains or hands. Point is, we are creatures with highly developed fine motor skills AND global positioning systems. We are creatures of rationality AND emotionality. We are creatures of severity AND gentility. The organism works best when these go together, not when we segregate.

Isn’t that cool?

Here’s how it relates to children – handwork. A child that is given lots of opportunity to explore and refine her digital dexterity will simultaneously develop those areas of her brain. When taken as a whole – fine skill and global orientation – the child has a great opportunity to comprehend her world, engage in it, and expand her education. But poorly defined limbs and fingers tend to produce under-developed brains, which often result in lack of comprehension and motivation. Imagine a child with highly developed finger skills, but a poor ability to orient her hand in space. Robot? Or, imagine a child that loves to look, but has a hard time motivating herself for specific tasks. Dreamer? Right. Left. Cooperation. That’s the jackpot. Nothing is a perfect solution, but sometimes the lack of motivation or global awareness we see in children can be treated simply by giving them handwork. It might work for us adults too.