IT'S ABSOLUTELY TRUE! (I'm using caps because I seem to be disagreeing with all previous posts - should use 20 point and mauve text.) Well, no-one really knows how much of our brains we actually use, but at any given time, its probably 10 % or less. How much of your muscles are you using at this minute? Or your spleen or large intestine? If I'm driving my five seater car alone with an empty trunk I could say I'm only using 10 to 20 % of my car. Right now, I'm using 0%. As you sit there reading this post (if I may be so presumptuous) your computer is using less than 10% of its processor chip's transistors and probably a lot less than 10% of its ram and disk memory.
Part of the problem here is that people tend to think of the brain as a single organ with a single function - thought. That is like thinking of the chest or the abdomen as a single organ, when in fact, it is made up of several distinct organs performing many distinct but interconnected and interdependent functions. The brain is made up of over 20 organs including hormone producing glands as well as the functions we associate with conscious and sub conscious thought. Even the neocortex, which is associated with the "higher" brain functions, (it is really unnecessarily pejorative to consider all the other brain functions as "lower".) performs a large array of functions, only a few of which are called upon at any given time. Same goes for your car and for most complex objects. Question: What organ is used to the lowest percentage of its potential? (Hint: See my user name.)
I recall hearing the 10% comment 50 years ago with the implication that we were only using our brains to 10% of its potential capability. And, as I recall, the statement was made by someone with a science background. Which just goes to show that scientists are quite capable, when occasion permits, of talking through their arseholes, since we still have little idea what the brain is capable of. There is another context in which we could argue that our brains (and all other organs) are being used to 99% (or 1%) of their capacity. When I use my 4000 pound car to drive my svelte, Adonis-like self around, what efficiency should I assign to that process? If I could attach wheels to my feet and shove a couple of cylinders and pistons up my ass, I could probably get about 500 miles per gallon. Every one of our brain cells (and all our other body cells) are working away all the time (even when we're sleeping) consuming nutrients, energy, and oxygen just to keep themselves alive. Only a tiny part of what we eat and breath is used by our cells for the function they are required to perform. We are really very incredibly inefficient things.
The evidence that humankind is de-evolving to a lower life form with minimal brain use is not the statement you quote, but that a certain Mrs. Sarah Palin is being considered for the vice presidency of the United States.
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