What? Just...what? How does this make sense? Why would we have these horrible lumps of grey flesh in our heads if we didn't use them? Our brains make human birthing one of the hardest in the animal kingdom. It's the reason we give birth to our babies far more prematurely than most other animals, and have to rear them for years before they can even walk â€” because if they developed any more in the womb, their heads would be to big to birth.The fact that we've had relatively accurate brain maps for decades should prove this fact wrong. How in the world would it make sense that we use less than the entire thing â€” barring brain injury? Sorry Tony Robbins, we don't have 90% of our brain's power left to unlock.