Capuchin picture
Sarah F. Brosnan, Ph. D.



Brosnan Photo

Contact Information:

Mailing address:
Georgia State University
Department of Psychology
PO Box 5010
Atlanta, GA 30302-5010 USA

Email: sbrosnan@gsu.ed
Phone: 404-413-6301

Sarah and Galapagos Tortoise


Summary of research interests

I am currently an assistant professor in the Department of Psychology at Georgia State University and a member of the Neuroscience Institute . I direct the Comparative Economics and Behavioral Studies Laboratory (CEBUS Lab) and do research with nonhuman primates at both the Language Research Center of Georgia State University and the Michale E. Keeling Center for Comparative Medicine and Research of the UT/MD Anderson Cancer Center.

My research interests lie in the intersection of complex social behavior and cognition. More specifically, I am interested in mechanisms underlying cooperation, reciprocity, inequity, and other economic decisions in nonhuman primates from an evolutionary perspective. This includes, but is not limited to, questions of what decisions individuals make and how they make these decisions, how their social or ecological environments affect their decisions and interactions, and under what circumstances they can alter their behaviors contingent upon these inputs.

One of my current projects compares three species of nonhuman primates and humans in their response to a cooperative economic game.  Often, these studies are not comparable due to methodological differences, minimizing the effectiveness of the comparative approach and providing little insight into the evolution of the behaviors.  We are currently investigating whether these species will cooperate when given the opportunity to do so and how factors such as partner identity, equity in payoffs, and the context of the task affect their performance.  This research is being done jointly at the Language Research Center of GSU with Michael Beran and with Bart Wilson at the Economic Science Institute of ChapmanUniversity.

A second major interest of mine is the evolution of responses to inequity.  This requires animals to take in to account both their own and others’ rewards or procedures, and makes subjective assessments of their outcome based upon these changing parameters, and likely involves emotional responses as well as conscious decision making.  In the past I have demonstrated this phenomenon in both capuchin monkeys and chimpanzees, as well as demonstrating that subjects take account of both the rewards and their partners’ behaviors and that social context affects reactions.  I have also investigated the flip side of inequity, or how individuals respond when they are advantaged, to more fully integrate this research with the human literature.  Currently we are working on assessing how group dynamics affect the response, how control of the situation alters responses, and the relative impact of inequity towards the self versus inequity towards another, as well as extending this research to other species. 

Finally, I am interested in barter, or exchange, behavior in nonhuman primates.  I have investigated how capuchin monkeys and chimpanzees understand the barter interaction, and ongoing work assesses their abilities to utilize a barter efffectively.  The exchange paradigm can also be effectively used to investigate other behaviors such as inequity and endowment effects.  I currently have several ongoing projects investigating barter and using the paradigm as a tool to investigate other pheneomena.

Links to sites of interest:

Language Research Center, Georgia State University
Keeling Center for Comparative Medicine and Research, UTMDACC

Living Links Center of the Yerkes Primate Center
The Gruter Institute for Law and Behavioral Research
FIRST Fellowship Program of Emory University - This innovative NIH funded postdoctoral program emphasizes reserach while giving fellows an excellent background in teaching and experience teaching in local historically minority serving institutions.
American Society of Primatologists

Animal Behavior Society