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IDEAS: Looking for That Brain Wave Called Love A runaway train is about to hit five men, and the only way to save them is by pushing the person next to you onto the tracks in front of it. Should you do it? Most people say no. To explain that response, philosophers have turned to Aristotle and Kant. Joshua Greene, a graduate student in philosophy at Princeton, turned to neuroscience instead: he took brain scans. Looking for moral reasoning in an M.R.I. machine? It sounds unlikely, but Mr. Greene isn't the only humanist in a brain lab these days. Lured by such sophisticated new technologies as functional magnetic resonance imaging, which essentially takes snapshots of the brain in action, scholars in philosophy, music and even literature are devising their own neuroscience experiments. At Rutgers, an anthropologist is investigating the neural circuitry of romantic love by putting besotted volunteers in a brain scanner and asking them to stare at a photograph of their beloved. At Harvard, a business professor is comparing brain responses to different advertising images, while an English professor is preparing to look at what happens in a reader's brain when she encounters a metaphor in Proust. At Rice University in Houston, a music professor is planning to study the cognitive basis for sight-reading. Even perceptions of racial difference have been examined in an M.R.I. machine. In academic disciplines where words have traditionally been the weapon of choice, the hope is that brain-scan studies might do what written polemics cannot: provide empirical support for pet theories and aesthetic judgments or help put to rest much-debated questions. "If there can be verification in the lab of what readers over generations have reported to be true, we might be able to learn something about the congitive basis for literary visualization techniques," said Elaine Scarry, the Harvard professor who is planning to study imagery in Proust and other writers. "Do novelists activate the same brain regions as daydreaming does? We just don't know." She and a psychology professor want to examine how novelists can create vivid images of solid objects in the reader's mind. One way might be to compare the brain activity that occurs when people are asked first simply to imagine a solid wall and then to contemplate, say, Proust's description of the cartoon figures from his magic lantern dancing over the wall of his bedroom at Combray. Using brain scans is so new to the humanities that many of the studies are still in the drawing board stage. And for that reason, some experts worry that the eight-year-old imaging technology, which generates detailed pictures of blood flow in the brain, might not be ready to take on the sort of complex problems that the humanities and social sciences study. While few think that brain scans are just a gimmick — 21st-century science's phrenology — some are urging greater caution in how the technology is used. "There's been a real rush to ask big questions and get sexy results," said Patricia Churchland, a philosopher of neuroscience at the University of California at San Diego. "When you're looking at a brain scan, you're really just looking at changes in blood flow. The presumption is that changes in blood flow correlate with higher neuronal activity. But how do we know what it means when the brain lights up in one area? It doesn't mean the brain has a module dedicated to that particular task." That hasn't stopped people from trying to map the neural pathways of such intangibles as ethics and love. Helen Fisher, the Rutgers anthropologist, believes that romantic love has three phases, lust, attraction and attachment, each one with a distinct pattern of brain activity. Initially she had a difficult time finding a collaborator in neuroscience to help her test her theory. "It's amazing how scientists don't regard depression or anxiety as a mystery but want to relegate romantic love to the realm of the supernatural," she said. When she first approached Lucy Brown, a brain scientist at the Albert Einstein College of Medicine at Yeshiva University, Ms. Brown was skeptical of the project. "It seemed rather frivolous," said Ms. Brown, whose own research focuses on Huntington's disease and the basal ganglia. "I thought it was too big a question to ask right now of neuroscience." Ultimately, Ms. Brown agreed to join Ms. Fisher's team. They are now in the process of investigating love's attraction phase by running infatuated subjects through an M.R.I. machine. While Ms. Brown "got a lot of flak" from her colleagues, neuroscientists at University College in London have been more enthusiastic, recently completing a study similar to Ms. Fisher's. They asked 17 subjects whom they deemed "truly and madly" in love to stare at photographs of their beloveds as well as photographs of three friends of a similar age and sex, using an M.R.I. to record the subjects' brain activity. When they stared at their beloveds, their brain activity was mostly restricted to the medial insula, the anterior cingulate cortex and the striatum — regions also associated with positive emotional states like sexual arousal and the euphoria induced by cocaine. "We have for the first time, localized the areas of the human brain involved in evoking one of the most overwhelming of all affective states, that of romantic love," the researchers wrote in a summary of their findings. They plan to present their work next month at the Society for Neuroscience's annual meeting in New Orleans. Consciousness — philosophy's signature subject — has also become popular among researchers trying to distinguish the way people say they experience the world from the way their brains automatically process what's going on around them. "`Consciousness' used to be the bad `C' word," says Frank Tong, a Princeton neuroscientist who studies the visual cortex. "It was too soft, not scientific. Now you can write a grant application with the word `consciousness' in it and actually get funding." This is not the first time a new technology has captivated scholars. In the late 1970's, points out Anne Harrington, a historian of science at Harvard and co-director of the university's seven-year-old Mind, Brain, Behavior Interfaculty Initiative, researchers were convinced that the computer would revolutionize the conception of the human mind. Descriptions of the brain as a data- processing center whose workings could be depicted in flow charts filled scientific journals. "It took 15 years to extricate ourselves from that model," she said. "The latest fascination is with seeing things light up in the brain." Still, Ms. Harrington is excited about the potential value of brain scan research. "Neuroscience has fantastic tools and methodology; I'm not sure we're using them to ask the most exciting questions. By asking appropriate questions, humanists can help brain scientists take these tools out for a real test drive." Two years ago Princeton threw its institutional weight behind brain research in the humanities by becoming the first nonmedical academic institution to finance an M.R.I. facility. To get the $2 million, 10-ton scanner into the basement of Green Hall, a 1927 neo- gothic pile that houses the university's new Center for the Study of Brain, Mind and Behavior, engineers had to lower it through a huge hole in the building's courtyard. "I wouldn't have come to Princeton if they hadn't promised me a scanner and with it the opportunity to collaborate with people in the humanities and social sciences in addition to neuroscientists," said Jonathan Cohen, who left a post in psychology at Carnegie Mellon to direct the center. When Mr. Greene, the philosophy graduate student, walked into his office looking for help with his moral reasoning problem, Mr. Cohen was thrilled: "I thought: `This is great. This project is why I came here.' " Mr. Greene wondered whether an M.R.I. study might shed some light on a conundrum known in philosophical circles as the Trolley Problem. In essence, the Trolley Problem asks why most people find it morally acceptable to flip a switch that would sacrifice one life in order to save five others, but morally unacceptable to push a person to his death in order to save those same five lives. The challenge for philosophers has been to come up with a single moral principle that justifies both responses. Perhaps one reason they have been unsuccessful, Mr. Greene speculated, is that as far as the brain is concerned, the two dilemmas are not that similar after all. In other words, what is lumped together under the term "moral reasoning" might turn out to be a set of distinct mental processes involving, in some cases, the brain regions associated with abstract reasoning and, in others, those associated with emotional responses. A brain scan study, he reasoned, might be a good way to test this theory. With the help of Mr. Cohen and another psychology professor, John Darley, Mr. Greene administered brain scans to nine undergraduates. For two hours each student lay on his or her back in the M.R.I. machine staring at a small mirror. One by one, a series of 60 different moral dilemmas, including some modeled on the Trolley Problem, were projected onto the mirror. After reading each, the student responded by pressing either a "yes" or "no" button on a handset attached to a wrist. The prediction was that different areas of the students' brains would light up depending on what kind of dilemma they were asked to solve. Mr. Greene said he could not discuss the findings because the study was under consideration for publication in a major scientific journal, but he described them as promising. "When a technology comes along that allows us not just to ask questions but to answer them, it's crazy not to use it," Mr. Greene said. "If I'd known more about brain imagining, I might have gone into neuroscience instead of philosophy." By EMILY EAKIN Copyright 2000 The New York Times Company http://www.nytimes.com/2000/10/28/arts/28BRAI.html janet paterson 53 now /44 dx cd / 43 onset cd /41 dx pd / 37 onset pd TEL: 613 256 8340 URL: http://www.geocities.com/janet313/ EMAIL: [log in to unmask] SMAIL: POBox 171 Almonte Ontario K0A 1A0 Canada