How much % of the human brain is been used? Is it true that a greater % of the brain is completely dormant ?

Question

How much % of the human brain is been used? Is it true that a greater % of the brain is completely dormant ?

Answer 1

No, it is not true.  Unless you have brain damage, you are using 100% of the brain.

Answer 2

Absolutely not true, as noted in the other answers and the reference that follows. Beyond this, one might argue that this is not a valid statement. What does it mean to use a % of the brain? Neurons in the brain fire electrical impulses, but one cannot argue that more impulses means more information (or more use) - just as much computational information is conveyed by a neurons silence as by its activity. So how could one ever estimate the percentage of brain used? Indeed, all neurons in the brain are "used" in the sense that they are connected to other neurons and influence the firing of other neurons.

Just in case, to point out just how facetious the question is: What percentage of your foot do you use? or your car?