Tales from Both Sides of the Brain : A Life in Neuroscience (9780062228819)

by Gazzaniga, Michael S.

  Still, we needed enticements to lure him to Davis. A short walk from our now-beloved center was an apartment complex. I asked Buck Marcussen, my administrative assistant, who could get an elephant to fly if need be, how we could rent one, given that UC needs four thousand approvals for everything. He figured this out. Then I went to Leo to ask how we could get an appointment for a visiting professor on an annual basis. He knew a way. Finally, I turned to one of our young fellows, the captivating and articulate Helmi Lutsep, a young neurologist studying stroke patients, and an Estonian! I knew she would make Tulving feel welcome. It even came to light that Helmi’s father had gone to high school with Endel, meeting in a displaced persons camp in Germany after World War II. Helmi got hold of an Estonian flag and hung it up next to a picture of Endel as a young man, which had made its way from her father. I don’t know what he expected Davis to be like, but certainly it surprised him. We all became fast friends and have remained so for twenty-five years (Figure 40).

  FIGURE 40. Enjoying a moment with Endel (front left) and Ruth Tulving (front right), their daughter Linda (standing), and other lifelong friends. The Tulvings were passionate supporters of Estonia and bought an apartment there after the breakup of the Soviet Union.

  (Courtesy of the author)

  Tulving’s contributions to the field of cognitive science were already legendary. He had firmly established that we humans enjoy at least two kinds of memory, semantic and episodic.10 Semantic memory deals with things we learn, such as the rules of the chess game. Episodic memory occurs when you remember actually playing a particular game of chess: the experience and the episode, so to speak. Tulving was now going after the question of whether these two kinds of memories were located in different brain regions. The new brain imaging technologies now existed to test such questions, and he tackled them with the energy of a twelve-year-old. His door was open at 9 A.M. and didn’t close until 7 P.M. His intellect, energy, and, best of all, character were always on display. And right behind him was his adoring and patient wife, Ruth, who was a world-famous artist in her own right and a member of the Royal Canadian Academy of Arts.

  Ruth became rather famous locally for her paintings, which she called “Butterflies of Davis.” They were intricate, beautiful, and stunningly original. They became the signature for their time in Davis and now hang all over the world. What is so interesting about Ruth and Endel is that while she seemed almost invisible with Endel around, she was the engine that kept it all going, from gracious hosting, to fabulous meals, to supportive conversation, to just about everything. Endel would lovingly say, “My bride has put up with me for fifty years.”

  Ruth died in 2013 after a two- to three-year illness that robbed her of her memory, her ability to speak, and ultimately her ability to cogitate. After enjoying a lifetime of shared intellect and interests, her condition was especially heartbreaking for Endel. Endel’s response was powerful. Up until her illness, he’d never lost a minute working on his passion, the problem of human memory. When it became apparent Ruth was truly ill, when all the clever dodges patients use to hide their internal deterioration were revealed, Endel stopped all of his work and cared for her in a way that was both moving and seamless. Not a moment of pity, regret, complaint, or despair. As Endel put it to me, “Ruth took care of me unselfishly for fifty years. Now it’s my time to take care of her. Let’s have a Manhattan.”

  Endel was a magnet to students. During one of his terms, he discovered a new student of mine, Michael Miller. Mike wanted to study false memories, yet in good graduate school fashion, he was mandated to take rotations outside of his area of interest. He somehow managed to be reassigned to Endel, and as Mike puts it, “I certainly learned everything I know about memory from him. I used to sit in his office for hours while he talked about episodic memory. We even devised a little paper-and-pencil memory test on orthographic distinctiveness* that I tested on a bunch of subjects. It was a blast.”11

  What happens in full view when expert meets motivated novice is so exciting and fulfilling to watch. The novice can’t get enough of the expert, and the expert needs a jolt from the novice. Usually, both people, if they are good-spirited, learn.

  When Endel began his Davis visits in 1993, he was totally consumed by the new brain imaging data, especially that coming from PET studies, which measure the parts of the brain that are metabolically active when doing work. Endel was interested in the moments when the brain was either encoding new information or retrieving stored information. Add to that Endel’s famous distinction between memory for events (episodic) and memory for knowledge (semantic) and you have a complex question on the table. Do these processes call upon the same brain systems to work or will the fancy brain-imaging techniques reveal that the processes are managed by different parts of the brain? Spending a little time on this leads to many, many complicated questions.

  Take polysemous words, a single word that can have several different meanings. My favorite is the word line. One can get in a “line,” read a good “line,” have a “line” on a great deal, walk the “line” with Johnny Cash, and so forth up to twenty-six other meanings. Some of those meanings are more likely used for episodic memories and others for semantic memories. Are the twenty-six meanings of the word filed away separately in the brain or is there one storage spot and other mechanisms that come in to give the word context?

  Psychologists are among the world’s most clever experimentalists. While the physical and biological scientists are dealing with stuff that is tangible, psychologists are dealing with “abstractions,” or “representations,” or “attitudes,” and on and on. It is a much more difficult science, much more slippery, and the experimental designs to get at it are much more trying. Endel, with youthful enthusiasm, was wading in to the PET measurements with a sense that he would be able to provide new and hard evidence that indeed multiple systems in the brain carry out these various yet seemingly similar tasks.12 His impeccable standards of science and his persistent energy in relation to a question sucked in all of those around him. Naturally, Mike became intrigued. Even though he was working on other problems at the time, he decided to work on this one, too. Over the next few years an army of people jumped into the discussion.

  Solely using the imaging data, Endel and collaborators, who by now were strung across the country, originally unearthed a pattern of brain activation that suggested that the left and right prefrontal lobe regions of the human brain were separately involved in the encoding and retrieval of episodic and semantic memory.13 The prefrontal areas, those territories way at the front of the brain that were not commonly thought to be part of memory circuits, were, they discovered, active during memory tasks. That, in and of itself, annoyed many people. But there was more. Endel’s team felt that the left prefrontal areas were more active when a subject was retrieving verbal semantic memories, while the right hemisphere prefrontal regions were more active when retrieving episodic memories. Added to this was the idea that the left prefrontal areas also kicked in when encoding episodic information of a novel kind. Whew. Distinctions, distinctions, and more distinctions.

  One can immediately see the complexity of possibilities here, and the field of cognitive neuroscientists who worry about this kind of thing are still hashing it out over the paper written while Endel was at Davis.14 I was in the background basically watching all of this when Mike suggested we get off our duffs and test the idea on split-brain patients. Up to that time, the issue of memory processes in these patients had languished with only a couple of observations. Not surprisingly, these had been two conflicting observations. One study suggested that the patients experienced memory deficits15 and another that they did not.16

  The question came down to whether the two half brains behaved differently now that they were disconnected from each other. The Tulving model would suggest that the left hemisphere would not be as good at retrieving episodic memories and that the right would be poor at retrieving semantic memories. What Mike found was something diff
erent, and this is where split-brain patients offer such elegant answers to complex questions.17 One can simply ask a disconnected left or right hemisphere what it can or cannot do. In this case, Mike showed that each side could pretty much both encode and retrieve information of all kinds. What he also found, however, was that the left side was better at verbal information, and the right side at handling visual information, such as faces. In other words, each hemisphere has its specialization. The hemisphere that specializes in the kind of information being presented performs better on that kind of information. It has nothing to do with semantic memory versus episodic memory.

  Overall, it was beginning to look like each hemisphere’s recognition memory* system behaved similarly, as long as the testing stimuli were not playing to a particular hemisphere’s strong suit. Each side could encode and retrieve new information. Having said this, however, I am left wondering. Endel is rarely incorrect. I should probably plan on doing more experiments.

  TRAINING THE NEXT GENERATION

  Everywhere I went for almost thirty years, people were interested in the split-brain patients and what they were teaching us about brain organization. Anatomists; physiologists; developmental, perceptual, and cognitive scientists; evolutionary psychologists; and philosophers all wanted to know how their work might be illuminated by the studies. The added benefit of all this attention was that I came to know people across a broad range of scientific fields. The vast fields of neuroscience and cognitive science rarely mingled, and the leaders of all the specific disciplines hardly knew each other. Yet I found myself knowing them all. And I knew as plain as day that they would all benefit from working together.

  I had begun managing the summer institute in cognitive neuroscience at Dartmouth Medical School in 1989. It was originally funded by the James S. McDonnell Foundation to bring together on a regular basis investigators from disparate fields and young scientists being trained in these fields. The notion was to expose them to a broad base of methods, approaches, and bodies of knowledge from neuroscience, medicine, psychology, linguistics, computer science, engineering, and philosophy. When we moved to Davis in 1992, we had arranged that the summer institute move as well. Leo Chalupa and Emilio Bizzi took charge of the two-week school, which was now in its fourth year of existence. The idea was also born that we should meet every five years to start a regular stock-taking of the field by specialty. To each meeting, each specialty area would invite eight additional scientists, all leaders in their discipline, to have an intensive meeting of self-examination. That calculated out to almost one hundred scientists coming to one place for three weeks. I thought it would be grueling, if not impossible. We wanted each participant to write a chapter about their work, and we had arranged that MIT Press would publish it all in one huge reference book.

  With all due respect to Davis, it seemed unlikely that its 110-degree summer was going to be alluring. We were worrying about where we might pull this off when in walked a young Brit, the vibrant Flo Batt. She was the original let-me-solve-it person with a lovely British accent to boot. We hired her to manage the complex project. After just a few weeks, I was sure that she must have worked for the queen of England. She wrangled and sweet-talked and cajoled. Everything worked out for us to have the entire three-week event at the Resort at Squaw Creek, near Lake Tahoe in the Sierra Nevada mountains, which was the right place to be in the summer of 1993 (Figure 41). It was and is fantastic. We continue to have a meeting there every five years, with all the goodwill that was set up by Flo. The most amazing thing about the experience is that I sit at the back of the room for every lecture. That is not my usual way, but for some reason, this event is like no other.

  FIGURE 41. The very first Tahoe meeting lasted for three weeks. Virtually every fellow here has gone on to have a distinguished career in the field.

  (Courtesy of the author)

  The book that comes out of this meeting every five years has become the reference standard in the field. Its consumers, the working cognitive neuroscientists, have even been caught reading chapters outside their own fields. The idea worked, and it worked because the section editors and the publishers were all behind the effort. Starting with the second edition, consisting of all new chapters and several changes of participants, my daughter Marin became the managing editor in her spare time.18 Meanwhile, my wife was running the Journal of Cognitive Neuroscience, and my daughter Kate was launching the new Cognitive Neuroscience Society. It was beginning to look like a family business.

  Deciding to launch a scientific society is a very iffy business, full of doubt, politics, money concerns, and just plain angst. What if nobody shows up? Who is going to underwrite the set costs of hotels, coffee, and meeting rooms? What if the leaders in the field don’t show up? What if it is a bridge too far? We talked it around and around. Finally, it was time to act.

  My old formula was put in place. Let’s pick a place people like to visit. San Francisco it was. Let’s look at a classy hotel, so I went to check out the Fairmont. They had a room that would hold four hundred, which at the time looked like the Los Angeles Coliseum to my worried mind. I began to learn about hotel contracts, minimums for room use, and on and on. They needed a deposit, so out came my Visa card and, gulp, five thousand dollars was plunked on the table. The Buckley/Allen debate at the Hollywood Palladium flashed through my mind, but without Steve Allen to slake my anxiety.

  The die was cast. Now it was time to nose around for some exposure. Just like in the movie The Magnificent Seven, calls went out to friends across the country. Mike Posner at Oregon (who was awarded the National Medal of Science in 2009) joined the effort, as did Dan Schacter, who was then at Arizona and about to become one of the world’s experts on human memory; Patti Reuter-Lorenz, my postdoctoral fellow, who is now a professor at the University of Michigan; Art Shimamura, then an assistant professor and now a full professor at Berkeley, a memory expert who is also interested in art and aesthetics; and, of course, Ron Mangun at Davis. I asked Steve Pinker, now one of America’s most prominent psychologists and public intellectuals, if he would be the keynote speaker (Figure 42). No problem. I then talked up the meeting, as did all my Davis colleagues, and, in the end, an absolutely stellar group of scientists showed up for talks and separately scheduled poster-style exhibits showing their research (Figure 43). Critically, key members of my staff from Davis caught the fever and came in to help manage the meeting. As it turned out, there had been little to worry about, as timing is everything, and everybody wanted the idea of cognitive neuroscience to work.

  FIGURE 42. The very first Cognitive Neuroscience Society meeting in San Francisco’s Fairmont Hotel. The keynote speaker was Steven Pinker.

  (Courtesy of the author)

  More than four hundred scientists showed up and the excitement was palpable. My idea for the society was that the administrative processes would be invisible to the participants. Let the scientists come and thrive on the science. Let’s not have business meetings and committees formed to worry about this and that. I guess it was naïve to dream of this scientific nirvana. Within a day, there was a spontaneous movement to hold a “business meeting,” and dozens of people showed up demanding representation and process and, of course, gender balance. Since it was pretty much my daughter and I who were running the society, we had nothing going for us but gender balance.

  FIGURE 43. The number of distinguished scientists who showed up at the meeting to support our efforts was stunning. Here, with the mustache, is V. S. Ramachandran, speaking between the shoulders of Richard Andersen (center) and Michael Merzenich (right).

  (Courtesy of the author)

  Over the years, the Cognitive Neuroscience Society has grown and thrived. First, the appearance and then the reality of structure took hold and with it more ideas for speakers, themes, diversity, and ultimately intellectual specialization. The original idea of the meeting was to have all participants hear a set of common lectures, the idea being that it would be broadening for scientists intere
sted in topic A to hear and keep up with advances in Topic B. Both the content and metaphor of other specializations can be enlightening. That simple idea has been almost impossible to realize. People have a deep need to promote their own knowledge and tend to have mental space only for the specifics of their own field. Interdisciplinary work is talked about all the time but is rarely achieved. Twenty years on, the society experiences the full grip of special interests and, unavoidably, becomes a mosaic. That is the way it goes. I have learned that I am an entrepreneur, but not a particularly good manager. I need to build it, and then gradually turn it over to others to run, even though it is emotionally draining to do so.

  Davis was fun and thriving. Why would anybody think about moving? The new hires were all in place, filling the Davis community with intellect, ideas, and work. Close friends had been made and the family was happy. We had lunches in Napa, weekends at our cabin in Tahoe, and visits to San Francisco. We were knee-deep in funding, weekly lunches with Leo at Biba’s, Sacramento’s only great restaurant, and regular visits from Endel and many others. Most important, we had a happy family. Yet through it all, I felt an irrational yearning for Dartmouth. It had started as an undergraduate, disappeared for twenty years, then popped up again when I worked at the medical school.

  This time, the college called me. Dartmouth, upon my departure in 1992, had invested in their cognitive neuroscience psychology department by hiring the distinguished neuropsychologist Alfonso Caramazza. He had arrived in town in his dazzling way, demanding better science and better food! As far as I knew, he loved it there and became the face of psychology to the administration. Lee Bollinger, the provost at the time and now president of Columbia University, took an immediate shine to him, and he instantly became part of the landscape. It looked like all was well.