Mike Gazzaniga
There are a number of ways to study the human brain. A list might include autopsies, animal studies (both surgical and behavioral), the big technical machines that can send information-detecting waves through bone, biopsies of removed tissues, medicines, stimulus/response studies, interviews, and so on. Michael Gazzaniga has specialized in studies of people who have had their corpus callosum severed, usually in attempts to eliminate or lessen the electrochemical storms we call epilepsy. The brain is in two halves, like the meat of a walnut, with a big connector bundle of axons between the two. Cutting it does’t kill the patient but it changes the brain’s thinking strategies.
(“So this guy is a brain surgeon? They’re really smart.”) Nonononono. He’s a Ph.D. Totally different. He never did any cutting himself, only worked with the patients afterwards to see how their thinking changed. It turns out that the brain, like the body, is bilateral, but more than that, each half specializes, one side noticing and managing different sorts of things than the other. (“Oh, I heard about that. One side is male and one side is female!”) Nononononono. (“Well, one can read and talk and the other side can’t.”) Closer, but still not there. (“Then the heck with you. It’s too hard to understand.”)
Now you’re really almost there. But the main thing that Gazzaniga uncovered was not just that the two halves of the brain each specialize in their own way of interpreting sensory information and producing responses, but that finally it turns out that there are thousands of small functions performed by the brain by interacting, timing, sequencing, filtering -- some of them so old that a flatworm does it (movement, digestion) and some of them so recent that only certain people can do it after they have reached a certain level of development. (Empathy.)
I’ve learned that I can understand complex technical material better if I read the stories of the people who have developed it. This is a basic human learning strategy. Gazzaniga’s story is as much an exploration of the way society learns as the content of the studies. Since he is a great big hearty guy who believes in family, good food, a certain amount of chemical lubrication in the form of refined alcohol, gracious houses, and elegant resorts where people let down their guard -- all without losing the focus of inquiry and without shutting out challengers. He knows how to network and where to find money. VERY useful and oddly inspiring information.
"Tales from Both Sides of the Brain"
by Michael Gazzaniga
The story begins with the realization that when people had surgically split brains, and if they had a card or divider edgewise in front of their noses so that their eyes were seeing separate things, one side (the eye cross-connected -- as eyes are -- to the side of the brain where words are located, one of the functions that’s NOT bilateral naturally) will see and recognize printed words and the other side will recognize objects, whether a geometric shape or an animal or thing. One side will not KNOW what the other one is seeing. Through the book, which is chronological and therefore means the insights develop over time, the story becomes ever more complex.
An artist's interpretation of the two sides of the brain.
The names of the split brain people are initials to semi-protect their identities, but with Gazzaniga running things they were soon celebrating birthday parties together and establishing life-long relationships. His wives and children were as involved and productive as every other category of people. In such an environment people work with joy and inspiration.
Mostly what they were doing was devising little puzzles that would get the brain to reveal what it can do or even how. They were like magician’s tricks, where attention is diverted or something unsuspected is going on. The brains were always inventing workarounds or figuring out ways to pass cues from one side of the brain to the other. It LEARNED -- one experimenter taught gorilla “sign talk” to the unspeaking side of the brain.
Two entirely separate "persons"
Forever looking for new angles, Gazzinaga considered the scary and hardly known phenomena of conjoined twins who had two whole heads, not just a split brain! https://www.youtube.com/watch?v=fiDCu83iJ1g The Hansel twins have two separate heads but each controls half of the rest of the body except that they share viscera so cannot be separated without killing them or at least one of them. Whatever happens at the visceral level, like mood or an upset stomach, is shared by both. Everyone wonders about sex, but I wonder more about love. Is it in the brain or in the guts? My guess would be both.
Normally such people don’t live long, much less to adulthood, but these women have each earned a bachelor’s degree and a driver’s license. They have learned how to coordinate their movements and sort of how to “read each other’s minds” in the way that Gazzinaga describes as like “old married people finishing each other’s sentences.” Split-brain people get to be a little like that so that after years pass, the differences between the two sides are reduced.
Two artists' interpretations of the two halves of the brain.
The book carefully describes the experiments, what prompted them, and what they revealed, sometimes something unexpected that no one had ever wondered about but that opened a whole new realm of brain questions. Often the answers are not at all dyadic -- not This or That -- but rather Both/And. Philosophers are forever trying to reduce matters to only two alternatives, but the strategy of the mind is clearly not merely two-sided at all, even with a drastic division. The recurrent metaphor is symphonic music, multiple but based on a group of cooperating individuals operating dynamically over time.
When the experiment was about cognitive dissonance, he came up with the idea of the “interpreter”. If one eye/brain saw one thing and the other eye/brain saw something else -- like a nude woman (eeks!), the person would explain their reaction -- which might be laughter -- by making up a little story. The descriptions are in the book.
Sarah Ioannides, symphony conductor
By now this idea of a part of the brain that could reconcile two incongruous things, the “interpreter”, has become the theory of an “operating platform” where all the information gathered and processed by the rest of the brain would be winnowed and reconciled. The notion of a big central nexus was soon joined by the theory that each of the senses (which are far more than five, which is only the number of obvious sense organs -- nose, ears, eyes) has its own filtering editor.
Two major human assumptions -- that we are identities who are permanent, unified, and consistent; and that what we believe we are perceiving is actually “real,” the “truth” -- have been blown out of the water. They simply are not “true” in the sense of inalterable facts, which is a great irony that is messing up our justice system, our relationships, our management of our lives, and just about everything else but the arts, which has welcomed these falling walls with excitement and vivid creations.
An inflatable conductor borrowed from a tire store.
Split brain research has been followed by beguiling researchers like Joe LeDoux (concentration on fear and anxiety) and Antonio Damasio (the puzzle of consciousness). Almost always the things we thought were "one" turn out to be complex interactions, some of them adapted from pre-existing abilities and sometimes by newly mutated abilities. Stayed tuned! There's bound to be a lot more!
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