Unless they only use brains that are dead (???)!!! Look what happened with a non-LA brain, at the end. And believe me, I feel the same way about them harvesting brains from Miami (FL). If they are more intellegent than earthlings, they came to the wrong planet to harvest brains!!!
shareHehe all American's are dumb asses, you picked the wrong country.
shareThis is true, but how old are the people who think we only use x% of our brains? This concept has been explained to be untrue years ago. I assume the people who still believe are either stupid, kids or american. Or all of the above.
shareAccording to this article people can function with only half of their brain.
http://en.wikipedia.org/wiki/Hemispherectomy
Check out the "further reading" links at the bottom of the article
not sure why nobody actually answered this question...
but unless it was entirely meant as a joke, the question doesn't exactly make sense, because they were harvesting brains from all over the planet.. at the end they showed other cities around the world.
the story we see is just following these certain people for whatever reason.
as for what % of the brain people use... work 3rd shift retail, there are plenty of people that use a very low percentage of their brains power. :)
also, not to argue the point of whether humans in general use all their brain power or not doesn't mean that 90% or 96% of the brain is completely not used, but it's like a car's engine if you step on the gas just a little you are only using a small percentage of the engine's power, that certainly doesn't mean you could remove 90% of the engine and it would still run.