Since we've all likely heard about the 10 percent rule, it's a cool dream to think that there's some inner-superhero inside us just waiting to be released. Unfortunately, the idea that humans only use 10 percent of their brains is as much a piece of fiction as Lucy's new abilities to control time and space.
"... the brain, like all our other organs, has been shaped by natural selection," Barry L. Beyerstein of the Brain Behavior Laboratory at Simon Fraser University told Scientific American. "Brain tissue is metabolically expensive both to grow and to run, and it strains credulity to think that evolution would have permitted squandering of resources on a scale necessary to build and maintain such a massively underutilized organ. Moreover, doubts are fueled by ample evidence from clinical neurology. Losing far less than 90 percent of the brain to accident or disease has catastrophic consequences."