Laurie Santos - US grants

This project explores the evolutionary basis of human irrational decision-making. In the past few decades, behavioral economics has observed that people demonstrate a number of systematic decision-making biases in both the laboratory and the field. To date, however, very little research has explored the origins of such biases. Do economic biases reflect learned behaviors that result from particular market experiences, or are these biases the result of more ingrained tendencies, ones that result from evolved and possibly innate mechanisms? This proejct investigates the evolutionary origins of human economic behaviors, including persistent biases such as gain-loss asymmetry and reference dependence. To do so, this project conducts a series of economic studies with a novel set of subjects, non-human primates. Although non-human primates lack market conditioning, they too face a variety of distinctly economic problems, such as coping with the scarcity of goods, assigning the limited resources necessary to acquire them, and managing risks inherent in their native ecology.

It is possible, then, that certain aspects of economic decision-making will follow from evolutionarily-specialized mechanisms designed to deal with primitive resource conditions that foreshadowed modern economies. This project introduces a fiat currency and trade to a captive group of primates and then verifies the results of these market experiments. The project then uses this method in a series of studies to explore primate preferences over a range of economic problems typically used to extract data describing human decision-making. These studies will be the first of their kind to determine whether human-like standards of rationality are present in our close primate relatives and, if so, whether homologous psychological architectures can explain rational choice in both species. Demonstrating that primates either do or do not share economic biases with humans will have implications for which policy interventions are likely to overcome such biases in human markets and can be used to develop new behavioral measures for future neuroscientific and clinical investigations of human economic biases.

The broad goal of this REU Site is to provide students with joint training in comparative and developmental psychology research. Students will gain experience investigating the origins of human social cognition from two different but related perspectives: developmental studies testing human children's social understanding and comparative examining social cognition in non-human primates, specifically capuchin monkeys. The REU site's 10-week program will host a diverse group of undergraduate students to work jointly in the Comparative Cognition and Social Cognitive Development Labs at Yale University. The REU students participate in all aspects of the research process: research design, subject recruitment, stimulus generation, data collection, data entry, coding, and statistical analysis. In addition, students have the opportunity to interact as colleagues: participating in weekly lab meetings, reading current literature, contributing to theoretical discussions regarding the comparative and developmental origins of social cognition, and attending a professional development series focusing on topics such as applying to graduate school, getting the most out of their undergraduate career, etc. Students meet weekly with a graduate student mentor, and the PI and co-PI attend bi-monthly social events. A primary objective of this REU site is to include students who have fewer research opportunities, including those attending non-Research universities and students from underrepresented groups and first generation college students. In this way, the PIs aim to increase the odds that these students will be competitive in applying to graduate school in psychology or a related field.

Intellectual Merit. The REU students will join a vibrant and collaborative research environment at Yale, one that emphasizes both undergraduate teaching and mentoring, but also cutting-edge research. Both labs have a history of running internship programs in which students actively participate in collaborating on and publishing exciting scientific research. These programs include students who do not have the financial ability to pay for the internship program themselves. In addition to being an ideal environment for undergraduate research, the topics explored in these labs are unique. This REU site is one of the few locations in the world where students can learn to study one topic (social cognition) from many perspectives including a comparative approach, a developmental approach and an adult social psychological approach.

Broader Impacts. The REU and the associated research have considerable broader impacts. The participants in this program represent a wide-swath and often excluded group of researchers including members of underrepresented groups, first-generation college students and students attending non-Research I universities. Aside from the broad impact on the professional development of the personnel involved, the students' research will focus on important social topics, spanning such important social issues as the origins and development of prejudice and discrimination, justice and morality, helping and altruism. In this way, this REU site provides broader impacts both in terms of student development and in terms of socially-relevant research findings.

This project is funded from the Research Experiences for Undergraduates (REU) Sites program in the SBE Directorate. The REU program has both scientific and societal benefits integrating research and education. The broad goal of the Comparative and Developmental Origins of Social Cognition REU Site is to provide students from under-represented backgrounds with joint training in comparative and developmental psychology research. Students will gain experience investigating the origins of human social cognition from two different but related perspectives: developmental studies testing human children?s social understanding and comparative studies examining social cognition in domesticated dogs. REU students will have a rare opportunity to participate in all aspects of the research process: research design, subject recruitment, stimulus generation, data collection, data entry, coding, and statistical analysis. In addition, students will have the opportunity to interact as colleagues: participating in weekly lab meetings, reading current literature, contributing to theoretical discussions regarding the comparative and developmental origins of social cognition, and attending a professional development series focusing on topics such as applying to graduate school, getting the most out of your undergraduate career, etc. Students will meet weekly with a graduate student mentor, and the PI and co-PI will attend bi-monthly social events.

A primary objective of this REU site is to include students who have fewer research opportunities, including those attending non-Research I universities and students from underrepresented groups and first-generation college students. In this way, this REU proposal aims to increase the odds that its undergraduates will be competitive in applying to graduate school in psychology or a related field. In addition, this REU site will be one of the few locations in the world where students can to learn study one topic (social cognition) from many perspectives including a comparative approach, a developmental approach and an adult social psychological approach.

This award was provided as part of NSF's Social, Behavioral and Economic Sciences Postdoctoral Research Fellowships (SPRF) program. The goal of the SPRF program is to prepare promising, early career doctoral-level scientists for scientific careers in academia, industry or private sector, and government. SPRF awards involve two years of training under the sponsorship of established scientists and encourage Postdoctoral Fellows to perform independent research. NSF seeks to promote the participation of scientists from all segments of the scientific community, including those from underrepresented groups, in its research programs and activities; the postdoctoral period is considered to be an important level of professional development in attaining this goal. Each Postdoctoral Fellow must address important scientific questions that advance their respective disciplinary fields. Under the sponsorship of Dr. Laurie Santos and Dr. Julian Jara-Ettinger at Yale University, this postdoctoral fellowship award supports an early career scientist investigating how humans and non-human primates understand the minds of others. As humans, understanding what other people think, feel, desire, and believe is central to successfully navigating our social world. However, we still know little about the extent to which our ability to represent others’ mental states is shared with other animals, impeding our understanding of human cognitive evolution and slowing the development of treatments for mental disorders involving deficits in these skills.

Deficits in theory of mind (ToM) are core components of developmental and neuropsychiatric disorders including autism spectrum disorder, antisocial personality disorder, and schizophrenia, and have profound effects on social relationships, effective communication, and moral reasoning. Animal models have recently advanced our understanding of the neurophysiological mechanisms underlying diseases that affect social decision-making (e.g., Parkinson’s disease) and approaches for their treatment. However, outstanding questions about the cognitive mechanisms underlying primates’ ToM judgments have impeded the development of an animal model of ToM. This project draws on computational methods developed for modeling human ToM to overcome these challenges. By computationally modeling non-human primate (NHP) ToM for the first time, this project will elucidate which cognitive mechanisms humans and NHPs share when making judgments about others’ mental states. Additionally, the fellow will computationally identify new experimental designs that can powerfully distinguish between competing representational hypotheses about NHP ToM and will test free-ranging rhesus macaques to empirically evaluate these designs. This work will (1) contribute to our fundamental understanding of the evolution of ToM and the cognitive mechanisms that guide social behavior and (2) advance a NHP model of human ToM which will aid in our understanding and treatment of ToM-related mental disorders.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.