Quote Originally Posted by kr1Nx01
The "we only use 10% of our brains" statement is a bit misleading - a broad statement used to cover the general principal of normal brain function. What it really means is that our brains filter out so much information received from the outside world that only about 10% of it is actually utilized as final sensory input. It's a basic function of sobriety; without it, you would probably go insane (see below).

These filters can be bypassed with the help of psychotropic drugs, or removed with the help of knowledge.

If you were to compare an MRI of a normal sober person to an MRI of that same person on LSD, you'd see that in the first MRI, only about 10-20% of the brain is mapped with activity; the second would show the majority of the brain mapped with activity. This is because LSD's primary function is to open previously-unopened channels in the brain and remove many filters imposed by normal brain function (a normal dose of LSD is almost COMPLETELY metabolized within 30 minutes, so it's not the drug's agonism itself that makes you trip for 8 hours, but the previously unexplored pathways it opens). LSD is psychomimitec, and when an MRI of a person under the influence of LSD is compared to that of a mentally ill patient, little difference can be noted.

So basically, if we "used all of our brains", we would become a race of insane, or at least would appear so to any people left still "only using 10% of their brains".


Addressing the original question, read up on Plato's theory of the divided line of knowledge. It's an interesting topic that pretty much covers your thoughts on this matter.
Severing the Corpus Callosum (The little piece of tissue that connects both hemispheres of your brain) is sometimes done to reduce the number of seizures with people that have epilepsy. The seizures occur because of too much activity going back and forth between your left and right sides of your brain. Of course there would be adverse effects of someone's brain suddenly turning into a supernova of electric activity. I'm talking about people evolving physiologically to handle that type of brain power...to clear up what I mentioned earlier.