Researchers find hormones affect voting behavior

Researchers from Rice University, the University of Nebraska at Omaha (UNO) and the University of Nebraska-Lincoln have found that hormone levels can affect voter turnout.

John Alford photo courtesy Jeff Fitlow/Rice University

As witnessed by recent voter turnout in primary elections, participation in U.S. national elections is low, relative to other western democracies. In fact, voter turnout in biennial national elections ranges from only 40 to 60 percent of eligible voters.

The study, published in Physiology and Behavior, reports that while participation in electoral politics is affected by a host of social and demographic variables, there are also biological factors that may play a role. Specifically, the paper points to low levels of the stress hormone cortisol as a strong predictor of actual voting behavior, determined via voting records maintained by the secretary of state.

“Politics and political participation is an inherently stressful activity,” said the paper’s lead author, Jeff French, the Varner Professor of Psychology and Biology at UNO and director of UNO’s neuroscience program. “It would logically follow that those individuals with low thresholds for stress might avoid engaging in that activity, and our study confirmed that hypothesis.”

“Finding a relationship between high cortisol levels and nonvoting raises the interesting possibility that changes that reduce voting stress, including convenient, familiar early voting locations, and less daunting ballots and voting machines, might help increase turnout by reducing the stress of voting in the high-cortisol population,” said John Alford, associate professor of political science at Rice.

To reach their conclusion, researchers collected the saliva of over 100 participants who identified themselves as highly conservative, highly liberal or disinterested in politics altogether and analyzed the levels of cortisol found.

Cortisol was measured in saliva collected from the participants before and during activities designed to raise and lower stress. These data were then compared against the participants’ earlier responses regarding involvement in political activities (voting and nonvoting) and religious participation.

“Not only did the study show, expectedly, that high-stress activities led to higher levels of cortisol production, but that political participation was significantly correlated with low baseline levels of cortisol,” French said. “Participation in another group-oriented activity, specifically religious participation, was not as strongly associated with cortisol levels. Involvement in nonvoting political activities, such as volunteering for a campaign, financial political contributions, or correspondence with elected officials, was not predicted by levels of stress hormones.”

According to the study, the only other factor that was predictive of voting behavior was age; older adults were likely to have voted more often than younger adults. Research from other groups has also pointed to education, income and race as important predictors of voting behavior.

In explaining why elevated cortisol could be linked with lower rates of participation in elections, French cited previous experiments in which high levels of afternoon cortisol are linked to major depressive disorder, social withdrawal, separation anxiety and enhanced memory for fearful stimuli.

“High afternoon cortisol is reflective of a variety of social, cognitive and emotional processes and may also influence a trait as complex as voting behavior,” French suggested.

“The key takeaway from this research, I believe, is that while social scientists have spent decades trying to predict voting behavior based on demographic information, there is much to be learned from looking at biological differences as well,” French said. “Many factors influence the decision to participate in the most important political activity in our democracy, and our study demonstrates that stress physiology is an important biological factor in this decision. Our experiment helps to more fully explain why some people engage in electoral politics and others do not.”

About David Ruth

David Ruth is director of national media relations in Rice University's Office of Public Affairs.