Political Passion: Brain Injuries Reveal the Circuitry of Political Intensity
- Lidi Garcia
- Apr 11
- 3 min read
A study of veterans who have suffered brain injuries has shown that certain areas of the brain can influence how much a person engages with politics. Damage to regions linked to decision-making and self-reflection increased this engagement, while damage to areas linked to emotions reduced it. This has nothing to do with being left or right, but with the intensity of political interest. The study helps to understand how the brain can affect our social behaviors and even our political engagement.
Have you ever wondered why some people become deeply involved in politics, participating in debates, going to demonstrations or closely following the news, while others prefer to stay away? And could something in our brains influence this more “intense” political behavior? Science is beginning to explore this intriguing idea.
A new study looked at war veterans who suffered severe brain injuries to understand whether certain areas of the brain are linked to how much a person engages politically, regardless of their ideological beliefs.
The results offer fascinating clues about how specific parts of the brain can influence our interest and engagement with politics.
Researchers at Harvard Medical School, USA, have discovered that a person's degree of political involvement, that is, how actively they engage with political issues, may be related to specific regions of the brain that process emotions and complex thoughts.
To investigate this, scientists studied 124 male U.S. military veterans who suffered penetrating brain injuries (when something pierces the skull and damages brain tissue) about 40 to 45 years ago.
These men are now middle-aged and participated in a study in which they were asked about their current political behavior and how involved they remember being in politics before the injury.
The researchers compared the injured areas in the participants’ brains with a large database of brain connectivity data from healthy people (with data from 1,000 individuals). This allowed them to identify which brain networks were functionally linked to the damaged areas. They looked at three main topics:
Intensity of political involvement (how involved the person is);
Political ideology (whether the person tends to be more liberal or conservative);
Party affiliation (which political party the person identifies with).
The most important finding was that the intensity of political involvement was linked to a specific brain circuit, while ideology and political party showed no direct relationship to brain areas.
People who had lesions connected to the left dorsolateral prefrontal cortex (a region associated with decision-making and behavioral control) and the posterior precuneus (an area linked to self-reflection and self-awareness) tended to be more intensely involved in politics.
This pattern was evident both in the overall sample and especially among participants with more conservative leanings.
Veterans with lesions connected to the amygdala (important in processing emotions) and the anterior temporal lobe (involved in memory and social recognition) tended to be less engaged with politics. This was especially true among participants with liberal leanings.
These results were confirmed by statistical validation tests, which reinforces confidence in the findings.
This study offers a new perspective on how our brains can influence our level of engagement with politics, not just our beliefs, but how much we engage emotionally and cognitively with these issues.
Furthermore, it shows that changes in the activity of certain brain regions, whether due to injury or other factors, can affect complex social behaviors such as political engagement.
In addition to advancing our understanding of the human mind, the results may also help doctors and mental health professionals better understand how brain injuries can affect patients’ social and emotional behavior, including their interest in politics.
READ MORE:
Effects of focal brain damage on political behaviour across different political ideologies Get access
Shan H Siddiqi, Stephanie Balters, Giovanna Zamboni, Shira Cohen-Zimerman, Jordan H Grafman
Brain, awaf101, 21 March 2025
Abstract:
Intense political behavior is associated with brain regions involved in emotional and cognitive processing. However, it remains unclear if this neuroanatomy is causal, compensatory, or otherwise correlated. We employed lesion network mapping in a cross-sectional study of 124 male military Veterans with penetrating head trauma. 40-45 years after the injury, participants reported current political behavior and recollection of political behavior pre-injury. Using a normative connectome database (n = 1000), we mapped the circuitry functionally connected to lesions associated with changes in intensity of political involvement, ideological polarity, and party affiliation. No significant neuroanatomical circuit was associated with political ideology or party affiliation, but a distinct circuit was associated with intensity of political involvement. Political involvement was more intense after lesions connected to the left dorsolateral prefrontal cortex and posterior precuneus, in the full sample and in conservative-leaning participants. Political involvement was less intense after lesions connected to the amygdala and anterior temporal lobe, in the full sample and in liberal-leaning participants. These effects survived cross-validation in the full sample (p=0.01) and in both conservative-leaning and liberal-leaning participants. These findings may inform cognitive mechanisms of political behavior as well as clinical assessment after brain lesions.
Comments