Pain sensitivity predicts support for political opponents

The idea that certain traits make someone more likely to be politically conservative or liberal has received a good deal of attention. Now, Spike W.S Lee and Cecilia Ma at the University of Toronto report finding an individual difference that is linked not to a person's own political affiliation, but to their level of support for some of the moral and political attitudes of their ideological opponents. 

This difference is sensitivity to physical pain. Across a series of studies on more than 7,000 Americans, Lee and Ma consistently found that liberals who were more sensitive to pain reported greater endorsement of some typically conservative stances. Those who were less sensitive, conversely, were less likely to be moved by conservative ideology. 

The researchers used the well-validated Pain Sensitivity Questionnaire (PSQ) in their research. This questionnaire describes 17 commonplace experiences, such as 'You burn your tongue on a very hot drink', and asks participants to rate how painful they imagine that would be on a 10-point scale. 

In three initial studies, participants completed the PSQ and rated their political orientation on a scale from extremely liberal to extremely conservative. They also completed measures of disgust sensitivity, emotional reactivity, anxiety, anger proneness, and empathy, all of which have been linked to moral attitudes. 

Finally, they completed the Moral Foundations Questionnaire. This questionnaire assesses the extent to which people prioritise five domains in moral decision-making. Two of these domains, care/harm and fairness/cheating, are generally thought to be more important for liberals than conservatives, though not all the findings on this are clear-cut. Work also suggests that the other three domains — loyalty/betrayal, authority/subversion, and sanctity/degradation —  are prioritised more by conservatives than liberals.

In all three studies, Lee and Ma found that higher pain sensitivity predicted greater endorsement of the three 'conservative' moral foundations. Interestingly, this association was stronger among liberals than among conservatives. It also predicted stronger support for the two 'liberal' moral foundations more strongly among conservatives than liberals (without undermining levels of support for the moral foundations typically linked to the participant's own political affiliation). 

These findings held even when the team controlled for scores on the other measures known to relate to moral attitudes, such as disgust sensitivity. Their analysis also showed that people who were more sensitive to pain were no more likely to be politically moderate, so variations in the strength of their political affiliation could not explain the findings, either.

In further studies, the team found that participants who were more sensitive to pain reported stronger support for a range of contentious political attitudes that are typically held by their ideological opponents. 

Some of the more pain sensitive participants reported greater support for opposition politicians — and were even more likely to vote for the ideologically opposed candidate in the US 2020 presidential election. However, the researchers stress, the key phrase here is "some of". Not all highly pain sensitive liberals voted for Donald Trump; far from it. Still, pain sensitivity (or at least factors associated with it) did seem to draw some people towards voting that way. 

A fresh study explored the researcher's hypothesis for why it might play a role. In this study, of more than 1,600 people, Lee and Ma found that people who are more sensitive to pain perceived that more harm would result from violations of the moral foundations typically associated with their ideological opponents. (For example, a highly pain-sensitive conservative would have been more likely than a less pain-sensitive conservative to feel that cheating would be harmful.) This finding is important for understanding the results as a whole, the researchers believe.

Both physical and social pain (resulting from exclusion, for example) share some neural bases, and research shows that there is overlap in the way our brains represent our own pain and someone else's pain. "This suggests that individuals with higher sensitivity to their own physical pain may be more sensitive not only to their own social pain but also to others' physical and social pain," the researchers write. And this is why, compared to less pain sensitive people, they might feel that violations of moral foundations other than those typically associated with their political views would cause more harm — leading them to place a greater value on these moral foundations (and on political attitudes in which these moral concerns play a role). 

As the researchers put it, for a liberal, if their ideology and media diet already tell them that racism, sexism, and inequality are immoral, their level of pain sensitivity is unlikely to influence their perceptions of the levels of harm caused by these things. But it could influence their perceptions of harm from violations of more 'conservative' moral beliefs. 

There are limitations to the conclusions we can draw from the study, however. The findings might fit with the researchers' interpretation of what is going on, but there could be other explanations. As they acknowledge, more work is needed to tease apart the influences of physical and social pain sensitivity, and to explore the precise nature of the role of harm perception in the effects. Still, the consistent evidence that someone's degree of pain sensitivity relates to their support for political opponents' views is certainly interesting. 

Read the paper in full: https://doi.org/10.1037/pspa0000355