Leon’s most famous work started with a small grant from the Ford Foundation to study and integrate the work in mass media and interpersonal communication. He and his colleagues took on the project, and to hear him tell it, the seminal observation came from considering a 1934 report about an Indian earthquake. The fact that puzzled them was that after the earthquake, the vast majority of the rumors that were circulated predicted that an even worse one was coming. Why, after such a horrendous event, would people want to provoke further anxiety? Leon and his colleagues concluded that it was a coping mechanism that the Indian people had developed to deal with their present anxiety. In other words, since the earthquake had filled the population with grief, they had formulated an even greater future tragedy, which cast the present moment in a better light. It was out of this basic observation that the theory of cognitive dissonance was born. It would take seven years of hard work to nail down all of the parameters of the phenomenon, but nail them down he did.
Leon carried out one of his early experiments with his two close friends, Stanley Schachter and Henry Riecken. Although a real group of people had been studied, he chronicled the story with a fictitious character and place. As the story goes, the group had come to believe the flood prophecy of one Mrs. Marian Keech. Months before the day of the flood, the following headline and news report had appeared in the Lake City Herald:
PROPHECY FROM PLANET CLARION. CALL TO CITY: FLEE THAT FLOOD. IT’LL SWAMP US ON DEC. 21, OUTER SPACE TELLS SUBURBANITE
Lake City will be destroyed by a flood from the Great Lake just before dawn, Dec. 21, according to a suburban housewife. Mrs. Marian Keech, of 847 West School Street, says the prophecy is not her own. It is the purport of many messages she has received by automatic writing, she says. . . . The messages, according to Mrs. Keech, are sent to her by superior beings from a planet called “Clarion.” These beings have been visiting the earth, she says, in what we call flying saucers. During their visits, she says they have observed fault lines in the earth’s crust that foretoken the deluge. Mrs. Keech reports she was told the flood will spread to form an inland sea stretching from the Arctic Circle to the Gulf of Mexico. At the same time, she says a cataclysm will submerge the West Coast from Seattle Washington to Chile in South America.7
Now, your ordinary scientist might have stayed as far away from this as possible. I mean really—this is National Enquirer stuff, and potentially hazardous to one’s career. Well, not Leon. He and a team went to Lake City forthwith, where Mrs. Keech received another message: On December 20, an extraterrestrial visitor was to appear at her house around midnight to escort her and her followers to a parked flying saucer and take them away from the flood, presumably to outer space.
Leon’s prediction, assuming that the momentous event did not occur, was that the followers would attempt to reduce their dissonant state, produced by not having their beliefs confirmed, by attempting to convince others of those beliefs. A vast set of experimental data now supports that view, but at the time it was brand new. The clock struck twelve in Lake City. The group waited. No alien visitor arrived to take them to them to a flying saucer. An awkward period began among the believers waiting in Mrs. Keech’s living room. But a few hours later, Mrs. Keech received another message:
. . . For this day it is established that there is but one God of Earth and He is in our midst, and from his hand thou hast written these words. And mighty is the word of God—and by his word have ye been saved—for from the mouth of death have ye been delivered and at no time has there been such a force loosed upon the Earth. Not since the beginning of time upon this Earth has there been such a force of Good and light as now floods this room and that which has been loosed within this room now floods the entire Earth. As thy God has spoken through the two who sit within these walls has he manifested that which he has given thee to do.
Suddenly, the room was in better shape, and Mrs. Keech reached for the phone to call the press. She had never done this before, but now she felt that she must, and soon all the members of the group had called various branches of the news media. For days this sort of justification went on, and Leon’s prediction was spellbindingly confirmed.
All of this came from a man who loved to play backgammon for hours on end. Unlike many academics, who talk a great deal without listening, Leon was a conversationalist. That back-and-forth reinforced his game behavior. Like all the truly great intellects I have known, he both listened and elicited testimony from the speaker. Being lectured to or lecturing himself turned him off. In the long run, what was so captivating for me was experiencing his insistence on avoiding the trap we all fall into: being transfixed by simple correlations and conclusions. He always dug below the surface.
The eloquence of cognitive dissonance theory surely guided me toward my ideas on brain modularity and belief formation, which I wrote about in The Social Brain many years later. Those priceless lunches and road trips to faraway places, including archaeological digs, all taught me about the richness of psychological concepts and provoked my thinking. My life was changed forever by knowing Leon. It was the scope and intellectual energy he brought to everything, from potato pancake recipes to complex mathematical formulations about brain scan data. His canvas had no boundaries, nor did his friendship. I had never experienced anything like it.
BACK AT THE LAB
Meanwhile, the work on motivation and reinforcement was moving forward. Premack had given me one of the experimental systems he’d built for testing motivation mechanisms. He liked an idea of mine that followed up on one of his theories and happily provided me with the gadget to test it. It was a device he’d rigged to allow a rat either to run in a wheel or to drink water. More specifically, the device was able to measure the responses of a rat when it did either. My question was, Would an adipsic rat (a rat that will not drink as the result of a specific brain lesion) drink if it was rewarded with an opportunity to run? Rats normally love to run, and if deprived of doing so, they will seek ways to run. If the adipsic rats would start to drink in order to have that opportunity to run, it would urge a more dynamic view of brain function and caution against the ever-growing tendency to see rigid one-to-one models relating structure to function. In fact, we learned that adipsic rats gladly drank if that was what they had to do in order to run (Figure 16).8
FIGURE 16. In order to get the activity wheel to spin for ten seconds, the rats had to take five sips of water. They were soon drinking like drunken sailors.
(Courtesy of the author)
Again, in some sense we were seeing a cross-cueing strategy that allowed the brain, a dynamic, ever-changing system constantly in action, to switch strategies in order to accomplish a goal. In this case, the experimenter was creating new contingencies (if you do this, then you get that) that evoked new strategies. More generally, it revealed that it was probably always dangerous to claim that a particular brain network has a monopoly on any particular behavior. The brain is wily and does not follow simple rules. If one network is knocked out, a detour is rigged. It was a striking and, to my mind, an important finding, but, as it sometimes goes, it has been largely ignored.
Still, once hooked on the idea, I tried all kinds of experiments to further demonstrate that specific functional parts of the brain are very much a part of an inherently dynamic system. In one wild experiment, I tested monkeys with inferior temporal lobe lesions that rendered them unable to learn the difference between two visual patterns for a food reward. I wondered whether they would learn the new discriminations if they were given the opportunity to run in a large monkey wheel I had specially built for them. Here I discovered that I had more in common with monkeys than I’d thought. Monkeys hate to run in a wheel. Instead, a group of temporal-lobe-lesioned monkeys actually learned new discriminations in order to lock the wheel so it wouldn’t move!9 Capitalizing on that preference for a stationary wheel, I found that visual capacity developed in monkeys even though the neural pathway that normally enables such visual learning was missing.
Same point, different species.
FIRST STEPS INTO THE NEUROLOGIC CLINIC
I had finally contacted the New York University School of Medicine with the hope of studying neurologic patients with disorders such as global aphasia—patients who could not use or understand language due to a brain lesion of the left cerebral hemisphere. It is a devastating condition and it puzzled me. Was it that the remaining intact right hemisphere couldn’t cover for the left hemisphere, or was it that the tests used to try to elicit language function were poorly designed? Both Leon’s and Premack’s psychological perspectives were pounding away in me.
Requesting to work with patients in New York was no simple matter. How? Where? Who says? When? These are the kinds of arrangements that require a planned process and tremendous staging. Once again, luck was with me. NYU School of Medicine had a storied neuropsychology* group, once led by Hans-Lukas Teuber, who had moved on to be the head of brain science at MIT. With him gone, I went in to meet the then-chair of neurology only to learn he was most definitely not interested in neuropsychology and claimed to have barely heard of Teuber. But, as I say, luck was with me, and someone put me in touch with NYU’s Martha Taylor Sarno, their expert on aphasia, and a research project was born. By then I was learning that everything in New York comes with a story, and I remember one in particular.
It was Thanksgiving Day. I got a call to get up to NYU for a special testing of a patient. We had a car by then, so I drove up to the medical center on First Avenue. Now medical centers have long swaths of street parking reserved for M.D.s, who are easily identified in New York since they have their identity stamped on their license plates. On a normal business day, one would never park there unless authorized to do so by virtue of possessing one of these plates. Its being Thanksgiving, however, no one was using the spaces. I was in a hurry, parked my car in one of the normally coveted places, and went in to see the patient. All was well until I came out to drive home. There it was, a freshly minted parking ticket. I was furious because it made no sense to me. After all, I was doing medical research on a holiday for the good of humanity, or something like that. I chose to fight the ticket and sent off letters to the city, the whole bit.
About three weeks later, I got a call in my office at work. It was the New York City parking commissioner. He said, “Say, Doc, we got your letter and we agree with you. Your ticket has been waived, canceled, forgotten.” I said, oh that’s great, then he added, “Now, Doc, you teach at NYU, right?” Yeah, I said. He said, “So listen, my daughter goes there. I want you to do me a favor. I want her to be able to call you if she ever gets in trouble, okay?” Holy smokes! I was really in New York now. Everything and everybody is leveraged.
Back in Santa Barbara, Premack had moved on from studying motivation and instead was testing the mental structures of a chimp by teaching her crude communication skills. It too was groundbreaking research with immediate possible implications for patients suffering left hemisphere stroke. Again, our simple idea was that a stroke patient with a damaged left hemisphere had a whole intact right hemisphere that might be able, if trained correctly, to compensate for the left’s damage in some way. David and I had wondered about this before I left for the East. Why couldn’t we teach an aphasic the kind of metalanguage system his chimp had learned, which would allow for a crude kind of communication from the remaining right side of the brain? Maybe we could open up untapped lines of communication with these devastated, largely mute patients.
Of course, I knew all about what isolated right hemispheres could do. We had worked for five years on getting right hemispheres of split-brain patients to do more than rule supreme on visual-motor tasks, such as the block design test. We knew that some of them could even read simple nouns. Scant data existed, however, on how well the right hemisphere could think symbolically. Premack’s chimp work pushed us to try the idea out. If chimps could learn a simple symbolic system, then why couldn’t a surviving right hemisphere?
What Premack had achieved with a chimp was inspired. He was able to show very elegantly that chimpanzees can do analogies. He reasoned that an animal can make a judgment of whether two objects are the same or different without understanding anything about the relationship between the two objects. He put it this way:
Sameness/difference is not a relation between objects (e.g., A same A, A different B) or properties, it is a relation between relations: For example: consider the relation between AA and BB, CD and EF on the one hand; and AA and CD on the other. AA and BB are both instances of same; the relation between them is “same.” CD and EF are both instances [of] different; the relation between them therefore is “same.” AA is an instance of same, and CD an instance of different; the relation between them is “different.” This analysis set the stage for teaching chimpanzees the word “same” for AA, and “different” for CD. When taught these words, chimpanzees spontaneously formed simple analogies between: physically similar relations (e.g., small circle is to large circle as small triangle is to large triangle), and functionally similar relations (e.g., key is to lock as can opener is to can.10
Now that is an ingenious analysis. On the surface it seemed unlikely a patient with a major language disturbance could match the feats of a chimp. It was time to do experiments. Along with my new NYU graduate student, Andrea Velletri-Glass, and with Premack, still in California at UCSB, we began. With airplanes, phones, and fax, it somehow worked. We studied several patients intensely and discovered that patients with left hemisphere lesions, who were rendered severely aphasic, could nonetheless learn, to varying degrees, the artificial language that was successfully trained to chimps. In other words, we thought at the time that in some of the patients, the spared right hemisphere could reason at least to the level of a clever chimpanzee.11
The right hemisphere was, we assumed, carrying out the cognitive work in these experiments. Some of the patients were so severely damaged on the left it was the only logical possibility. At the same time, our belief that the right hemisphere should be able to do at least simple tasks was challenged by another study we carried out at NYU.12 It deals with a phenomenon called “pure word deafness,” the inability to comprehend spoken words. Patients with this problem could still read and understand words presented to them visually, but they could not understand words spoken to them. This was caused by a specific left hemisphere lesion. Okay, we said. But these same patients also have right hemispheres that are working. Why can’t the right hemisphere take up the slack and understand spoken language? After all, the disconnected right hemisphere of some split-brain patients could understand spoken words. Remember, in those days we were still thinking in very simple ways about how the brain worked.
It wasn’t long before a patient came along who allowed us to test the idea—once again proving the richness of the neuropsychologic clinic. The natural accidents of nature provide unending insights into how our brains are organized.
Case W.B. had been a business executive when he suffered a stroke that left him with his strange inabilities. While he could read perfectly well, write perfectly well, and had a fairly normal audiogram (hearing test), he could not understand spoken language. So, show him the word knife printed out on a card and he could say it, write it, and find the object from a grab bag of objects. On the other hand, if you said the word knife to him, he was unable to make any meaningful response. In test after test this condition persisted for the rest of his life. This simple finding was the exact opposite result from what we expected as a result of our split-brain work.13 It got us thinking that maybe our thoughts about right hemisphere language were too general, too expansive. While there was no question that some language-understanding capability was present in the right hemispheres of N.G. and L.B., maybe they were the exception, not the rule. Maybe the positive finding that global aphasics were able to carry out simple chimp-level analogies was illusory as well. Maybe it was remnant parts of the left hemisphere carrying out that deeply cognitive task. Maybe, after all, most people only posses
sed language in their dominant hemisphere. Fifty years later, the field is still struggling with these questions.
CHALLENGING THE IDEA OF TWO MINDS
The tug of the new intellectual issues pushed by Premack and the weekly cross-examination about everything from Leon found me constantly reassessing the earlier claims Sperry and I had made about two minds in one brain. Added to this constant discussion were frequent trips to New York City by Donald MacKay, the sophisticated neuroscientist/philosopher whom I had brought to UCSB for a few months in 1967, and who also had issues with the first split-brain story of two minds. In tolerating the idea of two minds, Premack and Festinger gave moral support; meanwhile, MacKay simply didn’t buy it. Over martinis and Manhattans at Il Bambino, we tried to hash things out. Even MacKay, a physicist and a practicing Presbyterian, would throw back a Manhattan as we waited for the shrimp scampi to arrive.
Out of the blue, a request came in to write a review of split-brain research for the American Scientist, the journal of the Sigma XI organization. It was a good place to discuss such a grand issue as “one brain, two minds?,” which in fact became the title of my article. As I reread the article now, some forty years after I wrote it, I can see the tug-of-war that was starting in me. While I staunchly defended and argued for the double mind idea, I called upon the new kind of experiments and data I had developed at NYU. These would, in the long run, find me changing my views and facing a system much more complicated than the one I had defended.
Tales from Both Sides of the Brain : A Life in Neuroscience (9780062228819) Page 13
