Roger Sperry won the Nobel Prize in 1981 for his work on what is now commonly known as right brain-left brain thinking. Sperry theorized that some very specific activities were controlled by one side of the human brain or the other — for example, the right side controlled creative tasks, while the left side was where logic, language and reasoning lived. People were fascinated by the idea, and in the three decades since, bookstores, television, the Internet and college psychology classes everywhere have been filled with endless discussions of the differences between right-brain, left-brain, and whole-brain thinkers. (Ironically, Sperry’s...