Michael Gazzaniga was still a graduate student when he helped make one of the most intriguing discoveries of modern neuroscience: that the two hemispheres of the brain not only have different functions, but also operate independently—the so-called split-brain phenomenon.
A lover of fine wine and conversation, Gazzaniga, today a professor of psychology at the University of California, Santa Barbara, is also that rarity: a scientist whose life and work cross over into the humanities.
From his home in Santa Barbara, the author of Tales From Both Sides of the Brain: A Life in Neuroscience talks about where the next big breakthroughs in our understanding of the brain will come from, why a 14-day-old blastocyst isn't a human being, and how he came to meet Groucho Marx.
You are known for the discovery of the so-called "split brain." Remind us of the function of the brain's two hemispheres—and some of the popular misconceptions.
We worked on a number of patients with severe epilepsy. The surgery they underwent to control their epilepsy allowed us to study each half of the brain separately without one being influenced by the other. That was the advance. Classic neurology studied patients with holes in one side of their head from stroke or tumor or lesion and other kinds of traumas. Scientists knew that the left hemisphere was predominantly the verbal, analytic center, while the right hemisphere handled a constellation of things that were nonverbal.
But we were able to discover that the right hemisphere didn't know about the functions of the left hemisphere and the left hemisphere didn't have access to the information in the right hemisphere. Out of that came the left brain-right brain metaphor. It's been with our culture a long time and, of course, it got picked up and over-extended. I was skiing once in Colorado, struggling a bit, and some guy came zipping down the hill by me and he yelled: "Use your right brain!" [Laughs] Of course, it's a little more complex than that.
Your journey as a scientist began with an epiphany at Caltech 50 years ago. Take us back in time.
It was a wonderful experience. I was a new graduate student at Caltech at Roger Sperry's lab, and they were going to study this patient who was about to have his brain split. I was given the assignment of trying to figure out if there was going to be any impact on the behavior of the patient. There had been ten years of good animal research on both cats and monkeys, which showed the split-brain phenomenon. But people didn't think that could possibly be true in humans.
One of the reasons they didn't think so was that there had been a series of studies of patients in the 1940s who didn't really show anything after their callosum, the neural fibers connecting the two halves of the brain, was cut. This first patient who came to Caltech was going to give us another opportunity to look at that question. The reason a lowly grad student got the assignment was that no one thought that anything would happen. [Laughs]
We tested the patient preoperatively, showing that everything worked. If you put an object in one hand, the other hand knew about it. If you put an object in one visual field, the other visual field knew about it. Postoperatively, we rolled the patient back in for the exact same set of tests and, lo and behold! The patient could easily name objects put in his right hand, which projected to his left speaking hemisphere. But when the very same object was placed in the left hand, the patient said nothing was in his hand. The same was true for vision. It still takes my breath away.
Gazzaniga is clearly not an Irish name. Tell us about your family background and how it informs your life and work.
My heritage is Italian. My father's name was Dante Achilles Gazzaniga. His family was from a little town south of Pavia in Italy. In California, he became a physician and surgeon—a very dominant figure. He was very committed to education and educating his children. My mother loved social interaction, so there were always dinner parties at the house, friends over, and all that. There were five of us children, and we all went on to do good things. It was a no-nonsense sort of child raising. Lots of fun, but you worked all the time. You kept after whatever task you were doing. His children all reflected that, as do his grandchildren. [Laughs] I can't keep up with them.
You write that "the memorable peaks in life come scattered among the many hard and often dreary days of work." It's not a very American idea, where instant gratification is the watchword.
Almost every profession has a dreary component to it. Just dull, hard work. Then there are moments of great pleasure and insight and fulfillment. But it would be wrong for people to believe that a life in my profession—scientific research—is one happy party all day long. There's a lot of drudgery to it.
Steve Allen, the comedian, came over to Caltech one day. He was interested in these things. He said, "This work must be fascinating." I said, "Yeah, it is. But about 90 percent of it is just hard work." He recognized the same. And, of course, this is true for all of us.
You have rubbed elbows with some of the most famous scientists of the day, like Linus Pauling and Richard Feynman. You also became friends with a number of household names in the arts and journalism. Tell us about your friendships with the comedian Steve Allen and William F. Buckley, Jr., the conservative author and commentator.
When I was at Caltech, I got a job being a graduate student adviser. Part of my job was to run the student center, and I noticed the institution never invited conservative speakers to talk. There was this guy making his name at the time, William F. Buckley, Jr. So I invited him out to give a talk. It was a lot of fun, and that started a 50-year friendship.
Later, I put together a series of debates. I rented the Hollywood Palladium and had a debate on John F. Kennedy's foreign policy between Steve Allen and Bill Buckley. It was a 3,000-seat auditorium, but on the night of the performance only 200 tickets had been sold, so I was sweating bullets. Eventually, 3,000 people showed up.
It was a very lively debate and sitting in the front row was Groucho Marx. Buckley spots Marx and throws in a line. "Well, let's face it," he says. "John F. Kennedy's foreign policy might as well have been written by the Marx Brothers!" At which point, Groucho gets up and walks on stage, waving his hat. The place goes crazy!
Besides being a scientist, you are a lover of fine wine, music, and conversation.
One of my friends throughout the years was psychologist Leon Festinger. He was the person who discovered the concept of cognitive dissonance. He was one of the leading social psychologists in America and was a smart, smart, smart cowboy and a great conversationalist. He knew how to talk about all matters: political, social, scientific, the humanities. He could discourse on a pancake. [Laughs]
So, the love of conversation and discourse was pumped into my head early, and that just became part of my social life. You want that in your home; you want your kids exposed to that. You want to have conversations, and you want to have them with a wide spectrum of people. You don't want to get locked into one social view. Buckley was a conservative. Allen was very much a liberal. So having conversations with them was fascinating.
In a previous book, The Ethical Brain: The Science of Our Moral Dilemmas, you suggest that the brain may contain a built-in sense of ethics. Expand on that idea.
That's hard to believe with all the horrors of the current news. But there are seven billion people on Earth and, by and large, most of them get along. It's a very small percentage that is tearing each other up and making the world difficult for a lot of other people.
But how is it all these social interactions work? Are there built-in mechanisms of fairness and equality, trust and altruism? All these things that monitor our social response in a social world? The answer is: I think there are. The fields of moral psychology and moral neuropsychology are finding out which ones are part of our DNA. We are just beginning to unearth a lot of the underlying neurobiology for moral responses. What's emerging is how much can be constrained and overruled by social convention. That story is going to become a very large part of how we think of ourselves.
You have also written about the nature of consciousness as it affects the abortion debate. Talk about that.
I served on the President's Bioethics Council and a key question that comes up is whether a fertilized egg, a blastocyst, is a human. What we cherish, as human beings, are the memories and the things we can do that are managed by the brain. But there's no brain in the blastocyst. If you take a high-powered microscope and look at the blastocyst, you won't find a brain cell there. So, to give that a moral status as a functioning human being seems crazy.
Being human is the accumulation of life's experience and the management of your life. That's what's human. The issue we were approaching on the council was: Can a 14-day-old blastocyst be used for biomedical research? Is that an affront to the human condition? Ten out of seventeen experts did not have a moral problem with that. Interestingly, you couldn't predict how people would come out based on their beliefs. There were Catholics who said, "The blastocyst is fine." There were secular Jews who said, "No, that's not fine."
You say that most of the major scientific discoveries have been made in the past 50 years. What are the big breakthroughs likely to be in the next 50?
There have been tremendous technological breakthroughs in the way we can look at the wiring of the brain in great detail. And we're going to get better and better at really defining what it is.
The second big question is: "Well, how does it work?" That's where the next big effort and understanding will come: how the mind is enabled by the brain and how it all interacts together through time. That's where the breakthroughs will come.
If your left brain were having a conversation with your right brain about your life's most important achievements, what would each side say?
The right side would just list the names of my six children; my left side would tell you their glorious life history. It's nothing unique. I'm just a person who loves life, loves the family and the people you brought into this world.
What are we all trying to do? We're all just trying to be less stupid, right? Being less stupid is the goal of our families, and I've managed to communicate that to all our kids. So, we have a good life because of that. [Laughs] We're all out there just trying to be less stupid.
To learn more about scientific breakthroughs on brain research, read "Secrets of the Brain" in the February 2014 issue of National Geographic magazine.