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This is a very interesting video on Youtube featuring a patient with intractable epilepsy had his corpus callosum cut.
The Corpus Callosum is very high density collection of nerve fibers that transmit information to and fro both right and left hemispheres.
He was cured from the epilepsy but he remained with a split-brain. A right hemisphere disconnected from the left one and both working independent of each other.
Joe, the patient, doesn't feel this or recognize it at all. However, the condition could be demonstrated experimentally.
[Thanks to Mind hacks]