I know the left hemisphere and the right hemisphere now are working independent of each other, but you don't notice it. Now, you just kind of adapt to it. It doesn't, you don't have any feeling, it doesn't feel any different than it did before.
Seven years ago, Joe had brain surgery to allay the effects of severe epilepsy. His surgeon cut the nerve fibers connecting his left hemisphere with his right. While the operation was a complete success, Joe's unusual case... offers an extraordinary insight into the machinery of mind. This fiber system, the corpus callosum, is located midway between the two hemispheres.
When it was surgically severed in Joe's brain, the transmission of information between the two hemispheres was halted. Michael Gazaniga. What we can do is play tricks by putting information into his disconnected, mute, non-talking right hemisphere and watch it produced. behaviors and out of that we can really see that there is in fact a reason to believe that there's all kinds of complex processes going on outside of his conscious awareness of his left half brain joe i'm going to show you some things i just want you to tell me what you see and here we go you ready look right at the dot okay right okay you ready right at the dot grapes good when joe focuses on a point everything to the right of the point goes to his left brain the dominant hemisphere for language and speech so we can see here that when we flash a word or a picture joe is easily able to name it here we go see it close your eyes and let your left hand do a little work here Okay, what do you got there? Hand.
Okay, very good. Now, when a word or a picture falls to the left of a fixation point, that information goes to his disconnected right half brain. And as we can see here, Joe is unable to name it.
Joe is able to draw the picture with his left hand, the left hand getting its major control from the right half brain. What did you draw? Okay.
What did you see? A wheel on one side. I don't know where I saw another. So even though he can't name it, his left hand is able to draw out a picture of the stimulus, of the picture or word that we presented to his right half brain.
What did you see? I saw a hammer. So just close your eyes and draw with your left hand. Just let it go.
It's nice. What's that? Salt. Yeah.
What'd you see? Hammer. What'd you draw that for? I don't know.
What we have with Joe is a, is a, just a dramatic example of a neurologic case that really allows you this window into the non-conscious and how powerful non-conscious processes are at influencing our conscious self, our personal self. What Joe and patients like him, and there are many of them, teaches us is that the mind is made up of a constellation of independent, semi-independent agents. And that these agents, these processes can carry on a vast number of activities outside of our conscious awareness. Even though that goes on, there's some final stage or some final system, which I happen to think is in the left hemisphere, that pulls this All of this information together into a theory, it has to generate a theory to explain all of this, all of these independent elements. And so, and that theory becomes our particular theory of ourself and of the world.