Representations of Value in the Brain: An Embarrassment of Riches?

Over the past two decades, neuroscientists have increasingly turned their attention to the question of how the brain implements decisions between differently valued options. This emerging field, called neuroeconomics, has made quick progress in identifying a plethora of brain areas that track or are modulated by reward value. However, it is still unclear how and where in the brain value coding takes place. A primate study by Strait and colleagues in this issue of PLOS Biology finds overlapping signals of value coding in two brain regions central to the valuation process: the ventromedial prefrontal cortex and the ventral striatum. This finding reconciles the primate and rodent literatures, provides valuable insight into the complexity of value computation, and helps set the agenda for future work in this area.     

Embodied economics: how bodily information shapes the social coordination dynamics of decision-making

To date, experiments in economics are restricted to situations in which individuals are not influenced by the physical presence of other people. In such contexts, interactions remain at an abstract level, agents guessing what another person is thinking or is about to decide based on money exchange. Physical presence and bodily signals are therefore left out of the picture. However, in real life, social interactions (involving economic decisions or not) are not solely determined by a person''s inference about someone else''s state-of-mind. In this essay, we argue for embodied economics: an approach to neuroeconomics that takes into account how information provided by the entire body and its coordination dynamics influences the way we make economic decisions. Considering the role of embodiment in economics—movements, posture, sensitivity to mimicry and every kind of information the body conveys—makes sense. This is what we claim in this essay which, to some extent, constitutes a plea to consider bodily interactions between agents in social (neuro)economics.     

Consciousness meets neuroeconomics: what is the value of stimulus awareness in decision making?

An important question in neuroeconomics is how consciousness affects decision making. In this issue of Neuron, Pessiglione et al. take an initial step toward addressing this question by showing that humans learn to make optimal choices in the absence of explicit knowledge about key parameters of the decision-making problem.     

Identity economics and the brain: uncovering the mechanisms of social conflict

Social contexts can have dramatic effects on decisions. When individuals recognize each other as coming from the same social group, they can coordinate their actions towards a common goal. Conversely, information about group differences can lead to conflicts both economic and physical. Understanding how social information shapes decision processes is now a core goal both of behavioural economics and neuroeconomics. Here, we describe the foundations for research that combines the theoretical framework from identity economics with the experimental methods of neuroscience. Research at this intersection would fill important gaps in the literature not addressed by current approaches in either of these disciplines, nor within social neuroscience, psychology or other fields. We set forth a simple taxonomy of social contexts based on the information content they provide. And, we highlight the key questions that would be addressed by a new 'identity neuroeconomics'. Such research could serve as an important and novel link between the social and natural sciences.     

Choosing the greater of two goods: neural currencies for valuation and decision making

To make adaptive decisions, animals must evaluate the costs and benefits of available options. The nascent field of neuroeconomics has set itself the ambitious goal of understanding the brain mechanisms that are responsible for these evaluative processes. A series of recent neurophysiological studies in monkeys has begun to address this challenge using novel methods to manipulate and measure an animal's internal valuation of competing alternatives. By emphasizing the behavioural mechanisms and neural signals that mediate decision making under conditions of uncertainty, these studies might lay the foundation for an emerging neurobiology of choice behaviour.     

Neuroeconomics in parasitoids: computing accurately with a minute brain

In the so‐called ‘patch problem’, at any given moment, the forager must decide whether to leave the current patch or to remain there and continue foraging. Optimal foraging theory and subsequent theoretical works have identified theoretical optimal policies governing this decision. In a stochastic environment, the Bayesian framework has proved to be effective. A set of mechanistic proximal mechanisms explaining how parasitoid wasps may take decisions has been proposed. These mechanisms are based in on changes in the degree of motivation to continue foraging during a particular foraging episode. Using a simple, straightforward model, we show here that the psychological mechanism proposed mimics precisely the theoretical Bayesian solution, provided that motivation displays exponential decay, rather than the linear pattern of decay initially assumed. Changes in motivation thus function as a sort of analogue computer, and may be seen as more than purely heuristic rules of thumb. This link between psychological processes and ultimate optimisation places foraging theory in the domain of neuroeconomics.     

The European bitterling: a model for oviposition decision

For oviparous species, oviposition decisions can have significant fitness consequences. The European bitterling ( Rhodeus sericeus ) is a cyprinid fish that lays its eggs on the gills of freshwater mussels. Because bitterling use a discrete spawning site that can be readily manipulated, they are unusually amenable to field and laboratory studies aimed at understanding the adaptiveness and consequences of oviposition decisions. Here I present data demonstrating the adaptiveness of oviposition decisions by female bitterling, and link these decisions, using game‐theory models, with bitterling population dynamics. I explain the proximate cues used by females in making oviposition choices, and how these respond to environmental variables. I also show how the oviposition decisions of males relate to the risk of sperm competition in mussels, and propose that oviposition choices may represent an inter‐sexual conflict in bitterling. Finally, I present behavioural and genetic data from mesocosm experiments to show the implications of global and local male densities for female oviposition opportunities, and consider the consequences for bitterling population dynamics.     

The Joy Before Cooking: Preparing Ourselves to Write a Risk Research Recipe

Rather than the conventional practice of compiling a list of interesting research projects and then attempting to make the case that each represents a high priority, I will attempt an approach rooted in decision analysis. The information of greatest value, according to decision theory, is that which most enables us to make more reliable, transparent, and cost-effective decisions. Therefore, I begin with a brief discussion of how and why typical decisions relying on cancer dose-response information can fall short, in an attempt to assess where and how this aspect of risk assessment is “broken” before generating a list of research projects to “fix” it. I discuss the problem of model uncertainty in dose-response assessment, and conclude it is impossible to gauge how valuable it might be to know the correct model until we agree on guidelines for how to make decisions given imperfect information in this regard. After discussing four broad research areas that arguably represent particularly high priorities given this framework, I conclude by identifying three overarching areas of risk assessment and management that, if not given commensurate attention, threaten to render even perfect dose-response information of dubious value.     

MAOA-L carriers are better at making optimal financial decisions under risk

Genes can affect behaviour towards risks through at least two distinct neurocomputational mechanisms: they may affect the value assigned to different risky options, or they may affect the way in which the brain adjudicates between options based on their value. We combined methods from neuroeconomics and behavioural genetics to investigate the impact that the genes encoding for monoamine oxidase-A (MAOA), the serotonin transporter (5-HTT) and the dopamine D4 receptor (DRD4) have on these two computations. Consistent with previous literature, we found that carriers of the MAOA-L polymorphism were more likely to take financial risks. Our computational choice model, rooted in established decision theory, showed that MAOA-L carriers exhibited such behaviour because they are able to make better financial decisions under risk, and not because they are more impulsive. In contrast, we found no behavioural or computational differences among the 5-HTT and DRD4 polymorphisms.     

Patients with multiple needs for healthcare and priority to the worse off

There is a growing body of literature which suggests that decisions about healthcare priority setting should take into account the extent to which patients are worse off. However, such decisions are often based on how badly off patients are with respect to the condition targeted by the treatment whose priority is under consideration (condition‐specific severity). In this paper I argue that giving priority to the worse off in terms of condition‐specific severity does not reflect the morally relevant sense of being worse off. I conclude that an account of giving priority to the worse off relevant for healthcare priority setting should take into account how badly off patients are when all of their conditions are considered (holistic severity).     

THE WINDOW OF OPPORTUNITY: DECISION THEORY AND THE TIMING OF PROGNOSTIC TESTS FOR NEWBORN INFANTS

In many forms of severe acute brain injury there is an early phase when prognosis is uncertain, followed later by physiological recovery and the possibility of more certain predictions of future impairment. There may be a window of opportunity for withdrawal of life support early, but if decisions are delayed there is the risk that the patient will survive with severe impairment. In this paper I focus on the example of neonatal encephalopathy and the question of the timing of prognostic tests and decisions to continue or to withdraw life‐sustaining treatment. Should testing be performed early or later; and how should parents decide what to do given the conflicting values at stake? I apply decision theory to the problem, using sensitivity analysis to assess how different features of the tests or different values would affect a decision to perform early or late prognostic testing. I draw some general conclusions from this model for decisions about the timing of testing in neonatal encephalopathy. Finally I consider possible solutions to the problem posed by the window of opportunity. Decision theory highlights the costs of uncertainty. This may prompt further research into improving prognostic tests. But it may also prompt us to reconsider our current attitudes towards the palliative care of newborn infants predicted to be severely impaired.     

Biophysics of risk aversion based on neurotransmitter receptor theory

Decision under risk and uncertainty has been attracting attention in neuroeconomics and neuroendocrinology of decision-making. This paper demonstrated that the neurotransmitter receptor theory-based value (utility) function can account for human and animal risk-taking behavior. The theory predicts that (i) when dopaminergic neuronal response is efficiently coupled to the formation of ligand-receptor complex, subjects are risk-aversive (irrespective of their satisfaction level) and (ii) when the coupling is inefficient, subjects are risk-seeking at low satisfaction levels, consistent with risk-sensitive foraging theory in ecology. It is further suggested that some anomalies in decision under risk are due to inefficiency of the coupling between dopamine receptor activation and neuronal response. Future directions in the application of the model to studies in neuroeconomics of addiction and neuroendocrine modulation of risk-taking behavior are discussed.     

Language analysis in the United Kingdom's refugee status determination system: seeing through policy claims about ‘expert knowledge’

This paper examines claims made about the role of ‘expert knowledge’ in analysing the language of individuals seeking asylum in the UK. I treat policy as a type of power and seek to understand how this policy uses the language of science to further the British government's stated interest to provide ‘secure borders’ and a ‘safe haven’ for refugees. I look at how the Home Office defines, shapes and implements the policy, and at how the policy has influenced judicial decisions. In short I unmask UKBA's claim that it relies upon expert, scientific knowledge to assess asylum claims.     

Neuroeconomics: opening the gray box

The long-run goal of neuroeconomics is to create a theory of economic choice and exchange that is neurally detailed, mathematically accurate, and behaviorally relevant. This theory will result from collaborations between neuroscientists and economists and will benefit from input from other fields, including computer science and psychology.     

The evolution of mate choice and the potential for conflict between species and mate-quality recognition

Understanding how individuals select mates becomes complex when high-quality conspecifics resemble heterospecifics. Individuals facing such a situation may be unable to effectively identify both conspecifics (species recognition) and high-quality mates that can confer fitness benefits to the choosy individual or its offspring (mate-quality recognition). Here I suggest when a conflict may occur between species and mate-quality recognition, discuss the evolutionary consequences stemming from this conflict, and present a model of mate-preference evolution in response to heterospecifics. Determining how species and mate-quality recognition interact to shape mate-choice decisions is important for understanding the diversification of sexually selected traits among closely related taxonomic groups, the use of complex sensory systems for detecting mates, and seemingly inappropriate mate-choice decisions.     

Power, blame, and accountability: Medicaid managed care for mental health services in New Mexico

I examine the provision of mental health services to Medicaid recipients in New Mexico to illustrate how managed care accountability models subvert the allocation of responsibility for delivering, monitoring, and improving care for the poor. The downward transfer of responsibility is a phenomenon emergent in this hierarchically organized system. I offer three examples to clarify the implications of accountability discourse. First, I problematize the public-private "partnership" between the state and its managed care contractors to illuminate the complexities of exacting state oversight in a medically underserved, rural setting. Second, I discuss the strategic deployment of accountability discourse by members of this partnership to limit use of expensive services by Medicaid recipients. Third, I focus on transportation for Medicaid recipients to show how market triumphalism drives patient care decisions. Providers and patients with the least amount of formal authority and power are typically blamed for system deficiencies.     

Wnt/PCP proteins regulate stereotyped axon branch extension in Drosophila

Branching morphology is a hallmark feature of axons and dendrites and is essential for neuronal connectivity. To understand how this develops, I analyzed the stereotyped pattern of Drosophila mushroom body (MB) neurons, which have single axons branches that extend dorsally and medially. I found that components of the Wnt/Planar Cell Polarity (PCP) pathway control MB axon branching. frizzled mutant animals showed a predominant loss of dorsal branch extension, whereas strabismus (also known as Van Gogh) mutants preferentially lost medial branches. Further results suggest that Frizzled and Strabismus act independently. Nonetheless, branching fates are determined by complex Wnt/PCP interactions, including interactions with Dishevelled and Prickle that function in a context-dependent manner. Branching decisions are MB-autonomous but non-cell-autonomous as mutant and non-mutant neurons regulate these decisions collectively. I found that Wnt/PCP components do not need to be asymmetrically localized to distinct branches to execute branching functions. However, Prickle axonal localization depends on Frizzled and Strabismus.     

Hispanic Farmers and Farmworkers: Social Networks, Institutional Exclusion, and Climate Vulnerability in Southeastern Arizona

ABSTRACT   In the U.S. Southwest, prolonged drought may force those most dependent on water to abandon their livelihoods. By focusing on Hispanic farmers and farmworkers, in this article I examine how ethnicity and other factors compound risk and create highly vulnerable groups. I use the concept of "social capital" to understand how the critically vulnerable access resources embedded in informal social networks of mutual aid to reduce their vulnerability. By contrasting their situation to that of Anglo farmers, I explore how social networks emerge as a result of diverse socioeconomic and ethnic contexts. Under a more permanent scenario of increased aridity, a better understanding of the risk management mechanisms deployed by vulnerable groups sheds light on how collective approaches build resilience and on the role of policy in promoting or inhibiting these approaches. I seek to contribute to discussions about the importance of sociocultural dynamics and policy decisions to improving society's adaptive capacity.     

‘Aching to be a boy’: A preliminary analysis of gender assignment of intersex persons in India in a culture of son preference

Intersexuality, particularly in the global South, remains an under-researched field of study. In my in-progress doctoral research project, I explore the cultural, social, and medical discourses that influence how key stakeholders such as healthcare providers make decisions about the sex and gender assignment of the intersex child in India. In this paper I interrogate some of these ideas around gender assignment of intersex people in India, paying particular attention to the context of son preference. I am interested in exploring how decisions of gender assignment by medical professionals are guided by ideas of son preference. Focusing on four qualitative, semi-structured, in-depth interviews across two cities with medical doctors from different specializations, this paper is a preliminary attempt to examine some of the factors that guide medical professionals in making decisions about gender assignment of intersex children and explore the dynamics of the decision-making process. Specifically, I explore the factors that inform doctors’ decision-making and locate these decision-making processes within the broader socio-cultural context of India.