Neuroeconomics and the Governance of Choice in Time
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Social Studies of Science 41(4) 515–538 The shortsighted brain: © The Author(s) 2011 Reprints and permission: sagepub. Neuroeconomics and the co.uk/journalsPermissions.nav DOI: 10.1177/0306312710397689 governance of choice in time sss.sagepub.com Natasha Dow Schüll Program in Science, Technology & Society, MIT, Cambridge, MA, USA Caitlin Zaloom Department of Social & Cultural Analysis, NYU, New York, NY, USA Abstract The young field of neuroeconomics converges around behavioral deviations from the model of the human being as Homo economicus, a rational actor who calculates his choices to maximize his individual satisfaction. In a historical moment characterized by economic, health, and environmental crises, policymakers have become increasingly concerned about a particular deviation for which neuroeconomics offers a biological explanation: Why do humans value the present at the expense of the future? There is contentious debate within the field over how to model this tendency at the neural level. Should the brain be conceptualized as a unified decision-making apparatus, or as the site of conflict between an impetuous limbic system at perpetual odds with its deliberate and provident overseer in the prefrontal cortex? Scientific debates over choice-making in the brain, we argue, are also debates over how to define the constraints on human reason with which regulative strategies must contend. Drawing on ethnographic and archival research, we explore how the brain and its treatment of the future become the contested terrain for distinct visions of governmental intervention into problems of human choice-making. Keywords economics, epistemology, governance, liberalism, neuroeconomics, neuroscience, policy, rationality An undergraduate in jeans and a ponytail doffs her winter parka and climbs onto the bed of an fMRI [functional magnetic resonance imaging] machine. Joseph Kable, neuroscience postdoctoral researcher and economics neophyte, helps position the student’s head and body so that she will be able to keep absolutely still through the hundreds of choice trials she will Corresponding author: Natasha Dow Schüll, Program in Science, Technology, and Society, Massachusetts Institute of Technology, 77 Massachusetts Avenue, E51-185, Cambridge, MA 02139, USA. Email: [email protected] Downloaded from sss.sagepub.com at Bobst Library, New York University on October 17, 2015 516 Social Studies of Science 41(4) undergo over the next hour and a half. He hands the young woman earplugs from a half-empty industrial-size box and positions a mirror above her eyes to reflect a computer screen placed at the back of the machine. Kable leaves the room and shuts the door. The lights go out and the machine begins its roar. Outside the magnet room, where we watch through a glass panel alongside Kable, another screen flashes the first choice presented to the student inside the scanner: $212 in six months or $53 in two. Her answer is marked with a check: $212 six months from now. The next choice: $20 today or $50 in two months. Her answer: $20 today. (Authors’ fieldnotes, 2006) Since the late 1990s, a new space of scientific expertise has been emerging in the labo- ratories of elite universities, at the meetings of scientists and their public policy col- leagues, in Science and Nature and other academic journals, and in the popular media. Located at the intersection of neuroscience, economics, and psychology, the field of neuroeconomics converges around behavioral deviations from the model of the human being as Homo economicus, a rational actor who calculates his choices to maximize his individual satisfaction. Neuroeconomists look to the biological substrate of the brain for clues to the puzzles of consumer action – why people often make decisions to buy, sell, invest, and trade in ways that seem to go against their best interest. Going a step farther than behavioral economists, who argue that policy designers need to take seemingly ‘irrational’ choices into account, neuroeconomists insist that they need to understand how such choices get made in the brain. In this article we focus on neuroeconomic research into ‘future discounting’, or the tendency forego future well-being for immediate gratification.1 This particular puzzle, a longstanding concern of liberal governance, has become a flash point for the young field. In experiments such as Kable’s, above, neuroeconomists design tasks that can isolate and make legible the brain’s evaluations of rewards in and over time, operationalizing the future in the form of ‘inter-temporal choice’, or a choice between something now and something later. Inside the scanner, the subject weighs her preferences. How long is she willing to wait for a given amount of cash? As she trades off the value of money against time, the scanner takes pictures of her brain activity. In these images, neuroeconomists attempt to discern the neural mechanisms by which human beings value – and often undervalue – the future. In a historical moment when American policymakers increasingly link the short- sightedness of citizens’ microeconomic decisions to urgent problems – from individual conditions such as addiction and obesity to collective conditions such as the credit crisis and even global warming – there are high stakes to probing the neurobiological mecha- nisms underlying humans’ calculations (and miscalculations) about the future.2 Why do Americans spend today when the financial demands of retirement require saving for the future? Why do they keep reaching for candy bars and fried food when they know that heart disease can result from high calorie diets? Ongoing crises of economy, health, and environment challenge the notion that individuals can be expected to comport themselves according to the tenets of rational action; the model of human beings as prudent choice makers conflicts too starkly with the actual behavior that has triggered contemporary calamities. Although policymakers continue to encourage citizens to pursue their own self- interests as a path to maximizing collective well-being, they have begun to look to Downloaded from sss.sagepub.com at Bobst Library, New York University on October 17, 2015 Schüll and Zaloom 517 neuroeconomics for a model of the human being that can lend conceptual support to economic, social, and health policies designed to address a subject different from the traditional rational actor. By arming themselves with an understanding of citizens as fundamentally calculating, but also neurologically ill-suited to the contemporary land- scape of choice, lawmakers from Washington’s heights to the corridors of state agen- cies hope to design policy interventions that can accommodate both the capacities and limitations of human decision-making. But how exactly should these capacities and limitations be modeled? Within the field of neuroeconomics, there is heated debate around the mechanisms of future discounting, and the kind of model of the brain that best represents those mechanisms. Does future discounting reflect the constitutional myopia of a single value system within the brain, or an inner contest between impulsive and rational brain systems? In other words, should the brain be conceptualized as a unified decision-making apparatus, or as the site of conflict between an impetuous limbic system at perpetual odds with its deliberate and provident overseer in the prefrontal cortex? Does the problem lie with the brain as a whole, or in the balance between opposed neural systems? Although this debate does not neatly divide the field into its constituent disciplines, with all neuroscientists taking one side and all economists the other, it does fracture along epistemological lines: neurosci- entists trained in the experimental methods of natural science tend to favor a ‘single system’ model that can accommodate the complex morphological and functional con- straints of the brain, while economists’ strong theoretical tradition leads them to favor a ‘dual systems’ model that can reduce the brain and its functions into mathematically manageable formulae.3 As it turns out, each model of the biology underlying future dis- counting endorses a different vision of the human actor, different sites of accountability, and, potentially, different kinds of governance and remediation. When the neuroeconomics of future discounting is drawn into policy debates, what becomes of its impassioned internal debate? How do differing models of the brain influ- ence thinking about how, and whether, the government should regulate citizens’ choices in the long-term interest of individuals and the nation? Does it matter to policy whether choices derive from a unified or split valuation system? In other words, do epistemologi- cal politics bear any relationship to wider governmental politics, and if so, what kind of a relationship is it? These queries extend longstanding discussions among social scientists regarding the relationship between science and the broader social and political environment in which it is practiced. In the late 1970s, historians and sociologists of science argued that contexts of political insecurity and the clashing of rival beliefs in society at large could create conditions for novel and sometimes controversial scientific ideas to emerge, and that these ideas could loop back into public debate. Steven Shapin, for instance, showed how social and political concerns and values were debated and sometimes reconfigured in the so-called ‘phrenology disputes’ of 19th century brain science (Shapin, 1979). Our own