Reading the textbook a couple of weeks ago, I was quite surprised to come across a blurb commenting on the concept that people are either left-brained or right-brained. Basically, the theory claims that left-brained people are logical and do well in math and science, whereas right-brained people are more likely to be artistic dreamers and wander off on tangents. Supposedly, the dominant side or a person's brain affects the way in which they live and learn to a large degree and can affect their academic abilities.
As the book points out, however, there is very little solid evidence to support this theory. Both hemispheres of the brain are in fact in constant communication via the corpus callosum and other interconnections. While the theory may have worked well to explain personality differences back in the 1800's when it took root, we now have the ability to perform brain scans and other tests which prove that activities once thought to be strictly "left" or "right" brained such as spacial reasoning or language processing do, in fact, utilize both hemispheres.
I'll leave you with a few quick questions:
Why do you think that people were so quick to embrace the concept of "left-brained" versus "right-brained" differences and identify themselves as one of the other? Why are online quizzes which supposedly assess your personality and/or beliefs so wildly popular, and in what ways might this be beneficial or damaging to takers?