Study of voters' hormones may help to understand aggressive behavior

The presidential election, viewed through social media and media reports, generated bickering among friends and rallying to partisan platforms. Did your blood boil? Maybe our hormones were raging and led to aggressive behaviors, says a University of Oregon researcher.

Pranjal MehtaPranjal Mehta, an assistant professor of psychology, brought in voters to his lab — including some who were undecided until casting their ballots — before, during and after the Nov. 6 election. He's now analyzing their testosterone and cortisol levels for clues in their election-related behaviors and social interactions. And whether understanding such knowledge might help predict outcomes.

Mehta is pursuing his study under a newly awarded $75,200 grant (No. 1303743) from the National Science Foundation. He says his main hypothesis is that the strength of people's psychological bonds to their groups can be tapped to predict variability in neuroendocrine responses when they witness a "dominance contest" such as an election where contestants are seeking to obtain power.

"There has been research that has examined hormonal changes in individuals witnessing a dominance contest, but there are no empirical studies that have addressed the behavioral consequences of these hormone changes," Mehta says. "I am pursuing the idea that testosterone and cortisol may interact to modulate subsequent changes in aggressive behaviors and sociability."

Dominance contests can include physical confrontations such as fights, sporting events and wars. Non-physical competitions are school exams, job interviews and formal presentations. "Very little is known about biosocial processes involved in large-scale societal dominance contests such as democratic election," Mehta says.

Storage bags full of hormone samples in deep freezeIn the study, participants provided baseline hormone information through saliva samples taken in the lab. They continued to gather samples using kits at home.

Each subject also wore an electronically activated recorder that collected snippets of each wearer's behavior at regular intervals and self-report their moods in a booklet they had been provided. To remind participants to make entries in their booklets, they received automated text messages. Many of the participants also allowed Mehta's team to access three weeks of their social media activity, including interactions on Facebook.

In the summary of his NSF grant, Mehta writes: "While previous work has shown that observers' steroid hormone levels fluctuate after witnessing a victory or defeat, no empirical studies have examined the behavioral consequences of observers' hormone changes, and little is known about the psychological factors that explain variability in these hormone responses. The proposed work also addresses the onset and trajectories of hormonal and behavioral changes before, during, and after a high-stakes societal dominance contest."

The research also may have implications for theories of individual and group-based dominance hierarchies across multiple fields and for public policy issues. Ultimately, Mehta says, the findings may lead to new interventions to curb aggression and violence in such environments, and decrease stress and improve health in individuals and groups who perceive themselves as low status.

As a final crosscheck on the study participants, Mehta says his team will consult public voting information to confirm that they actually did cast ballots. All had reported that they were registered voters and intended to vote.

In the end, Mehta says, the research may be able to say whether hormones and social factors can predict voter turnout.

(Story by Jim Barlow)