What percentage of the brain do humans actually use?
The brain represents 3% of the body's weight and uses 20% of the body's total energy so, clearly, you are using more than 10% of it. The truth is that you are using a lot more of that noggin of yours than you think you are- pretty much all of it! Even when you are asleep, the frontal cortex, which controls self-awareness and somatosensory areas, is active. Source: Scientific American