We study the principles of human social behavior. As a social cognition lab, we are especially interested in the ways we process information about social groups. We study cognitive, physiological, and behavioral processes that are more "automatic" (fast, uncontrollable, unintended, or non-conscious). We ask questions such as: "How do my physiological responses to threats change when I have my 'people' around me?" and "When and how are my judgments of people biased by the social groups to which they belong?"

​A few of the main topics we have studied in the last several years include police officers' deadly force decisions, "Power Poses," and how coalitions manage outgroup threats.

Read below for more detailed descriptions of our ongoing research projects.

Video of police officer engaged in immersive shooting simulator. Insert in lower right shows the projected video being watched by officer during the task.

​In this line of research, we study the impact that  race and social class have on the decision to use deadly force.

We answer these questions using a range of methods, including an immersive shooting simulator. Participants watch first-person videos and make decisions to shoot firing a modified handgun. (See the video to the left for an example.)


In order to understand the underlying decision dynamics, we model responses as a drift diffusion process. This allows us to model three parameters of interest: starting bias (beta; e.g., people may be inclined to shoot when they see black targets); threshold level (alpha; e.g., people may require less evidence to make a decision for black targets); and rate of evidence accumulation (delta; e.g., people may accumulate evidence more quickly in dangerous neighborhoods). Hierarchical Bayesian modeling is used for parameter estimation.

It is critical to study this decision with actual experts trained to make these judgments. Thus we go beyond collecting data with untrained undergraduates and work directly with police officers. We have collected data with nearly 1,000 police officers across 5 different police departments in the Midwest. Reports of these studies are forthcoming.

Relevant Publications:

In addition to these controlled laboratory studies, we also analyze data from real-world shootings.


Relevant Publications:

Shooting Bias

​​Social interactions are influenced by the automatic (fast, uncontrollable, unconscious, unintended) responses that are activated upon encountering others. This line of research investigates the nature of automaticity at the cognitive, physiological, and behavioral levels.


Building on our earlier research, we start with the understanding that the perception of others initiates self-regulatory responses designed to prepare the body for effective interactions. Automatic responses are proposed to be the output of a computational assessment of what a person can and cannot do in response to the target, with current contingencies serving as input into this calculation. This framework is consistent with the understanding that the brain evolved as a computational organ to follow decision-making rules based on informational input from relevant sources, in the service of preparing the body for effective action.


Relevant Publications:



​​​​​Can holding "Power Poses" improve your life?
Please see this webpage summarizing our Power Pose research for more detailed information.

Much has been made recently of the possibility that holding expansive "power Poses" might have positive, life-transforming effects through a direct link between expansiveness and power. For example, a recent TED talk proclaims that holding power poses "can significantly change the outcomes" of the lives of low-status people.

We have instead understood the effects of physical pose as being one (and only one) input into a person's assessment of what they can and cannot do in a given situation and in response to another person. (For example, knowledge about whether you are subordinate or dominant should strongly dictate behavioral options.) If physical pose is only one input, then other inputs may be more important and override any effects of physical pose. This suggests that past claims about the incredible effects of holding power poses may be overstated if these other, competing variables are more relevant and sufficiently salient .

Relevant Publications:






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Michigan State University

East Lansing, MI 48824

This material is based upon work supported by the National Science Foundation under Grants 1230281 and 1756092. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.


The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of Michigan State University.