…the two sides of the brain always work together. And, crucially, people don’t have a “dominant” left or right hemisphere. We don’t think primarily with one part of our brain, which may be in a tug-of-war with other parts. —Stephen M. Kosslyn, Ph.D. and G. Wayne Miller
The left-brain/right-brain dichotomy is pop-psychology pseudoscience. Be suspicious of anyone touting it as a legitimate or insightful way of looking at human personality or cognition. — Steven Novella, MD
For the academic audience, read the paper.
The paper’s summary:
Neuroscientists now assert that there is no evidence within brain imaging that indicates some people are right-brained or left-brained. For years in popular culture, the terms left-brained and right-brained have come to refer to personality types, with an assumption that some people use the right side of their brain more, while some use the left side more. Researchers have debunked that myth through identifying specific networks in the left and right brain that process lateralized functions.