There's an optical illusion going the rounds on the internet involving the image of a spinning dancer.
According to internet misinformation, if you see the dancer spinning clockwise you are right-brained: creative, visual, etc. If you see her spinning counter-clockwise you are left-brained: organized, logical, etc.
With effort, she will begin turning the opposite direction for you (stare at her feet and blink --- it will happen, trust me). But your initial perception is supposed to be revealing of your deep brain orientation.
This is a dubious claim, scientifically. Some have (righty, I believe) rejected it.
Regardless of the conclusions you draw about this optical illusion of the spinning dancer, the larger issue that this left brain / right brain test brings up is the danger of applying crude psychological and cognitive categories to ourselves and our children. Every parent is familiar with the short-hand conversations we have with other parents:
While we're nearly tipping over a glass of wine, keeping one child from running down a set of stairs, and making a plate of beans for our other child, another parent at a party makes a comment about one of our kids. Soon we hear ourselves saying that our child is either:
extroverted / introverted
tough / sensitive
left-brained / right-brained
logical / creative
athletic / intellectual
cautious / risk-taking
happy / sad
an auditory learner / a visual learner
verbal / musical
a jokester / serious
Of course all of these oppositions are clumsy at best, damaging at worst. But they're so damn tempting! It's fun to tell other parents about the differences between my kids. It's downright fascinating to speculate about what their personalities will be like as adults. I know that I have to constantly remind myself: they can be both or all of these qualities or personality traits. They are never-before-seen combinations. They will figure out for themselves what they are; I don't have to do it for them.
We can't shy away from making observations. That's not what I'm saying. Our language is our language, crude and clumsy as it is. So we'll always overstate the case at times in the attempt to gain insight or test a hypothesis. Like astrological signs, or Tarot cards, or Freudian psychoanalytic terms (ego, superego, id), or even religious concepts (blessed, heavenly, angel, devil), our casual conversational categories can serve the purpose of enabling thought -- even when they have no basis in anything but language. They group behaviors and experience into understandable, digestable bundles. Sometimes they are useful for making choices about a child's learning environment. They are indeed a short-hand for messy experience.
But I hope never to forget that these categories are only flimsy boxes, made from cheap materials, useful for transportation (taking with us to parties) and sorting (discussing between parents), and that packaging materials should be thrown away. Haven't you read the warnings? Keep Away from Children. Danger of Suffocation.