Could neuroscience explain what Trump voters are thinking?

Political scientists are using neuroimaging to look directly at voters’ brain activity. Here’s what that research can tell us about the 2016 election.

As Donald Trump emerges as the Republican candidate for president, the 2016 election has more people than ever wondering what American voters are thinking and why. Enter the field of political neuroscience, which uses neuroimaging to bring research in biology, psychology, and political science together to see how the way our brains work affects our political behavior. We asked Ingrid Haas, director of the University of Nebraska’s Political Attitudes and Cognition Lab, what insights research in this growing field might give us about the 2016 election and the baffling rise of Donald Trump. 

ResearchGate: Does neuroimaging show that conservative and liberal voters’ brains work differently?

Ingrid Haas: Yes. There are only a handful of political neuroscience studies using MRI that have examined differences between liberals and conservatives, but the existing work does suggest that there are both structural and functional brain differences between these groups. Structural MRI can be used to measure the size and shape of specific brain regions, and work using that technique has shown differences between liberals and conservatives in the size of the amygdala, insula, and anterior cingulate—all areas involved in emotional processing and decision making. Beyond structural differences, research on how the brain functions uses what is called functional MRI, or fMRI to examine how the brain processes information by scanning people while they are doing a computerized task. This has also shown differences between Democrats and Republicans. So yes, there is some evidence that liberals and conservatives differ both in terms of how their brains are structured and how they function, but it is worth noting that this research is still very new. There's a lot we don't know yet!

Figure from a study on partisan differences in brain function. When performing a risk-taking task, Republicans more strongly activate their right amygdala. Democrats have higher activity in their left posterior insula. CC BY Schreiber et al., PLOS ONE 8(2), February 2013.
Figure from a study on partisan differences in brain function. When performing a risk-taking task, Republicans more strongly activate their right amygdala. Democrats have higher activity in their left posterior insula. CC BY Schreiber et al., PLOS ONE 8(2), February 2013.


RG: How do liberal and conservative brains differ? And how do they react to controversial statements—like building a wall, banning Muslims—that frame foreign citizens and domestic minorities as dangerous outsiders?


Haas: Research in psychology and neuroscience has shown that conservatives are more likely than liberals to respond to group boundaries and that they prefer clear distinctions between “insiders” and “outsiders.” Another set of studies has shown that conservatives are also more responsive to negative emotions, like fear or disgust, than liberals are. And, neuroscience work suggests that both ingroup-outgroup processing and negative emotional responses are related to automatic processing in emotion-related regions like the amygdala. So, for some conservatives at least, Trump's statements about reinforcing group boundaries and protecting the group from external threats are likely to resonate. And these messages are more likely to resonate with conservatives than they would with liberals.

RG: Now that he’s the likely candidate, many initially skeptical Republicans are warming up to Donald Trump. What hints can neuroscience give us about that process?

Haas: People can and do change their attitudes about political candidates when they receive new information, but this is more likely to happen when their existing attitudes are not very strong or they aren't certain how they feel about the candidate. However, if Republicans are motivated to win the election, it makes sense for them to support the party's nominee, and that may shape their feelings about Trump as a candidate. Neuroscience work has shown that motivation and goals can influence even automatic evaluations, decisions about whether something is good or bad, liked or disliked. Research also suggests that people often engage in “motivated reasoning” when they do have a strong opinion about something, meaning they are more likely to accept information that fits with their existing ideas, while rejecting conflicting information.

“When we dislike something, our brain gives a clear negative signal.”


RG: Both Clinton and Trump are historically unpopular candidates. How do voters’ brains react to candidates they dislike?

Haas: Our brains react to disliked political candidates in the same way we respond to other people that we dislike, and in some ways the signal is similar to how we think about disliked objects as well. When we dislike something, our brain gives a clear negative signal. We are also less able to think about the underlying causes of behavior in people we dislike, and this effect extends to political candidates.

RG: How might this reaction affect voting behavior?

Haas: Negative reactions not only make it less likely someone will vote for a candidate, but can also motivate people to go out and vote against a candidate they dislike. This is most likely if the negative emotion in question is anger. Anger is a powerful motivating force, because it is a strong negative emotion and leads to what psychologists call “approach behavior,” going out and taking action. On the other hand, if the reaction is related to other negative emotions, or to conflicted emotions, people may just be less likely to vote, and we might see decreased turnout.

RG: Would you say political neuroscience crosses a divide in research between social and natural sciences?

Haas: Historically, there has been a divide between the “social sciences" like political science and natural or human sciences like psychology, biology, and neuroscience, but increasingly we are seeing those walls or disciplinary boundaries start to fade. There has been a lot of interest in doing interdisciplinary work in recent years, and I think that interest will continue to grow. In terms of politics, there are now multiple subfields that focus on integrating politics and science: political psychology, bio-politics, political neuroscience. Political neuroscience helps to break down some of these boundaries by combining all of these fields, as psychology and biology are often integral to understanding and interpreting the results of studies that use neuroscientific methods to study political attitudes and behavior.

“There is still a lot of work to be done before we can really predict voting behavior based on brain data”


RG: Do you know of any current neuroscience studies based on the current election? What future studies do you expect to come out of it?

Haas: I don't know of any specific studies focused on the current election, but I would be surprised if no one is working on this. While there are still a relatively small number of people doing this type of research, there were a number of political MRI studies that focused on previous presidential elections, and I think work in that area will continue to grow. Studying political decision making during elections can help illustrate some of the basic principles guiding how people perceive candidates and how emotion and social attachments influence voting decisions. There is still a lot of work to be done before we can really predict voting behavior based on brain data. Still, I think we'll increasingly see progress in that area, especially research connecting functional brain data to real-world outcomes like voting using larger, more representative samples.

RG: Neuroscience seems very promising for political scientists in research settings, but it’s also being marketed as a strategic tool for campaigns. What do you think of this trend?

Haas: I think this is certainly an interesting trend and may turn out to be useful in the future, but in many cases it is an expensive alternative to more traditional, cost-effective methods of gathering information that work just as well, if not better. Neuroscience, and MRI in particular, can be a very effective tool for examining how people make decisions and the underlying brain processes behind them. But if you just want to know what people think about candidates or issues, that can often be gathered through traditional survey methods. I think at this point it's unlikely that campaigns would really need to spend the money collecting neuroimaging data, although it may become more useful in the future as we develop a better understanding of what those underlying processes are, and how they predict real-world outcomes.

Featured image: The amygdala, shown here as bright red, is one of the areas of the brain most commonly observed in political neuroscience. Courtesy of Tracy Abildskov