Using your 'other' hand benefits your brain

Using your 'other' hand benefits your brain

Recently I had surgery on my hand, leaving me functionally single-handed for a time. Here's the bad news: I'm right-handed and I was left a lefty. I soon learned that my two hands may look the same, but the left one does not behave as well as its preferred sister. I struggled. I looked ridiculous brushing my teeth with my odd hand, trying to start my car (how to turn that key?), and eating soup was nearly impossible. My left hand was quickly earning a reputation as a slacker. It seems it was left out when it came to coordination.

This bad rap for the left side is long rooted in history. In fact, the Latin word for "left" is sinistra, as in "sinister," while "right" in Latin is dexter, as in "dexterous." Everyone knows you're valuable if you're the right-hand man (or woman). Right just feels right and left feels all wrong for the 85+ percent of the human population that is right-hand dominant. I was out in left field with my left hand.

It turns out there are degrees of handedness, which can be evaluated using an objective scale called the Edinburgh Handedness Inventory. A full 55 percent of the American population is said to be "strongly right-handed," just 2 to 3 percent are "strongly left-handed" and the rest fall in between.

Yet, regardless of which hand you prefer, this preferred hand is hooked up to the opposite side of your brain. So my trusty right hand is connected to my left brain—the side responsible for language, judgment and intellect. But my clumsy left side is connected to my right brain, the source of creativity, perception and empathy.

There are many theories for how we become right- or left-handed—from sun positioning to location of your liver. "My theory is that we're frequently right-handed because we're language-dominant creatures and the left side of our brain—the part that processes the sound of speech—is usually larger and more dominant," says Carl Hale, Psy.D., neuropsychologist with Neuropsychology and Learning Associates in Merrillville and Fishers, Indiana. Others theorize that our position in the womb determines our handedness. They guess that the ear which faces out of the womb receives the most stimulation, which then stimulates the corresponding side of the brain.