The St. Petersburg Paradox is a famous economic and philosophical puzzle that has generated numerous conflicting explanations. To shed empirical light on this phenomenon, we examined subjects' bids for one St. Petersburg gamble with a... more
The St. Petersburg Paradox is a famous economic and philosophical puzzle that has generated numerous conflicting explanations. To shed empirical light on this phenomenon, we examined subjects' bids for one St. Petersburg gamble with a real monetary payment. We found that bids were typically lower than twice the smallest payoff, and thus much lower than is generally supposed. We also examined bids offered for several hypothetical variants of the St. Petersburg Paradox. We found that bids were weakly affected by truncating the gamble, were strongly affected by repeats of the gamble, and depended linearly on the initial "seed" value of the gamble. One explanation, which we call the median heuristic, strongly predicts these data. Subjects following this strategy evaluate a gamble as if they were taking the median rather than the mean of the payoff distribution. Finally, we argue that the distribution of outcomes embodied in the St. Petersburg paradox is so divergent from t...
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Humans may be patient when it comes to money, but chimpanzees are willing to wait longer than humans for food, suggesting patience is neither innate nor uniquely human.
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Abstract Functional magnetic resonance imaging (fMRI) and single unit physiology are two of the most widely-used methods in cognitive neuroscience and neuroeconomics. Despite the fact that practitioners of both methods share a common... more
Abstract Functional magnetic resonance imaging (fMRI) and single unit physiology are two of the most widely-used methods in cognitive neuroscience and neuroeconomics. Despite the fact that practitioners of both methods share a common goal–understanding the mechanisms underlying behavior and cognition–their efforts are rarely directly linked. Here we consider some of the reasons for apparent discrepancies between findings of fMRI and electrophysiological studies. We examine these problems through the lens of two case ...
Attention can facilitate visual processing, emphasizing specific locations and highlighting stimuli containing specific features. To dissociate the mechanisms of spatial and feature-based attention, we compared the time course of visually... more
Attention can facilitate visual processing, emphasizing specific locations and highlighting stimuli containing specific features. To dissociate the mechanisms of spatial and feature-based attention, we compared the time course of visually evoked responses under different attention conditions. We recorded from single neurons in area V4 during a delayed match-to-sample task that controlled both spatial and feature-based attention. Neuronal responses increased when spatial attention was directed toward the receptive field and were modulated by the identity of the target of feature-based attention. Modulation by spatial attention was weaker during the early portion of the visual response and stronger during the later portion of the response. In contrast, modulation by feature-based attention was relatively constant throughout the response. It appears that stimulus onset transients disrupt spatial attention, but not feature attention. We conclude that spatial attention reflects a combina...
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Efficiently shifting between tasks is a central function of cognitive control. The role of the default network - a constellation of areas with high baseline activity that declines during task performance - in cognitive control remains... more
Efficiently shifting between tasks is a central function of cognitive control. The role of the default network - a constellation of areas with high baseline activity that declines during task performance - in cognitive control remains poorly understood. We hypothesized that task switching demands cognitive control to shift the balance of processing toward the external world, and therefore predicted that switching between the two tasks would require suppression of activity of neurons within the posterior cingulate cortex (CGp). To test this idea, we recorded the activity of single neurons in CGp, a central node in the default network, in monkeys performing two interleaved tasks. As predicted, we found that basal levels of neuronal activity were reduced following a switch from one task to another and gradually returned to pre-switch baseline on subsequent trials. We failed to observe these effects in lateral intraparietal cortex, part of the dorsal fronto-parietal cortical attention n...
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The core feature of an economic exchange is a decision to trade one good for another, based on a comparison of relative value. Economists have long recognized, however, that the value an individual ascribes to a good during decision... more
The core feature of an economic exchange is a decision to trade one good for another, based on a comparison of relative value. Economists have long recognized, however, that the value an individual ascribes to a good during decision making (i.e., their relative willingness to trade for that good) does not always map onto the reward they actually experience. Here, we show that experienced value and decision value are represented in distinct regions of ventromedial prefrontal cortex (VMPFC) during the passive consumption of rewards. Participants viewed two categories of rewards-images of faces that varied in their attractiveness and monetary gains and losses-while being scanned using functional magnetic resonance imaging. An independent market task, in which participants exchanged some of the money that they had earned for brief views of attractive faces, determined the relative decision value associated with each category. We found that activation of anterior VMPFC increased with increasing experienced value, but not decision value, for both reward categories. In contrast, activation of posterior VMPFC predicted each individual's relative decision value for face and monetary stimuli. These results indicate not only that experienced value and decision value are represented in distinct regions of VMPFC, but also that decision value signals are evident even in the absence of an overt choice task. We conclude that decisions are made by comparing neural representations of the value of different goods encoded in posterior VMPFC in a common, relative currency.
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Research Interests: Science, Multidisciplinary, Synaptic Plasticity, Cats, Space perception, and 15 moreVisual Cortex, Brain Mapping, Humans, Animals, Retina, Neuronal Plasticity, Receptive Field, Neurons, Cortical Plasticity, Spatial Perception, Time Dependent, Time Factors, SYNAPSES, Action Potentials, and Normal Distribution
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Research Interests: Neuroscience, Physiology, Cognitive Science, Psychophysics, Molecular Biology, and 24 moreAnimal Behavior, Behavior, Peru, Systems Neuroscience, Nature, Shame, Learning, Memory, Seasonality, Computation, Model, Humans, Animals, Functional Imaging, Cortex, Nature Neuroscience, Profitability, Attitude, Tropical rainforest, Economic Model, Macaca Mulatta, Fruit Ripening, Neurosciences, and Choice Behavior
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Research Interests: Decision Making, Animal Studies, Animal Cognition, Behavioral Economics, Risk assessment, and 16 moreAdolescent, Biological Sciences, Reward, Humans, Risk Aversion, Gambling, Female, Male, Young Adult, Cultural difference, Beverages, Adult, Risk Preference, Risk Assessment, Reference Values, and Choice Behavior
Although still in the early stages, neuroeconomics—the union of ethology, economics, and neuroscience—offers a potentially powerful way to study the neural mechanisms underlying reward, punishment, and decision making, as well as the... more
Although still in the early stages, neuroeconomics—the union of ethology, economics, and neuroscience—offers a potentially powerful way to study the neural mechanisms underlying reward, punishment, and decision making, as well as the dysfunction of these systems in pathological conditions such as addiction. These neural processes interact in important ways with systems evaluating social context and uncertainty, and their study may lead to potent insights and testable predictions relevant to the neurobiology of addiction. ...