Of Mind, Brain, and Politics

• April 9, 2021
• Neuroscience, Politics

1. Introduction

Have you ever heard of the term—“neuropolitics”? I know; it sounds like I just made it up. But in fact, neuropolitics, or otherwise known as political neuroscience, is an emerging field of study at the forefront of political science and social cognition neuroscience that has become popular in the last two decades.

The poet JJ Bola once said in an interview, “Our existence is political — the choices that we make, where we decide to eat, where we buy our clothes, what school we go to, what languages we speak and where we speak them, how we speak…” (1) and I couldn't agree more. Politics is the play of power and influence on decision-making (2), and it does, in fact, play a role in everything that we do in life. Our behavior as a human, a creature of society, is deeply entangled in our own political reality. As an aspiring neuroscientist, I find this very interesting. How is it that the intricate connectivities of billions of tiny cells in our brain and their activities translate to opinions and beliefs that result in collective behavior out in society? Further, how is it influenced by social interactions and societal events?

Historically, there always has been deep philosophical opposition to the union of politics and the brain. The early philosophers like Aristotle, Plato, and Locke embraced dualism—the idea that the mind and the body are two distinct entities (3). This prevented, to an extent, the foray into exploring the material basis of the mind. However, over the last 70 or so years, the field of neuroscience has grown in leaps and bounds. Our understanding of the brain has reached levels unforeseen. With it has come new insight into decision making, belief formation, social behavior (4–6). All of which provide us with an opportunity to examine the connection between politics and the brain. In this essay, I shall attempt to discuss some of the current progress in neuropolitics and the future of this emerging field.

2. Politics on my Mind

Born from the intersection of political psychology, sociobiology, and cognitive neuroscience, the field of neuropolitics aims to study how political information is processed in the brain and is used to make decisions (7). One of the early experiments in this field was a simple one. The researchers presented faces of prominent personalities such as Adolf Hitler and Richard Nixon in split-brain patients to assess the difference in response to political stimulus between the two sides of the brain (8). Based on their results, they proposed that each hemisphere can independently code at least some degree of preference towards political figures. The study was not perfect. It lacked nuance and made many logical jumps, but it was a start.

The actual process of consolidating this field began in the early 2000s when scholars from many academic fields started to recognize the potential of applying understanding from cognitive neuroscience to the study of politics. An idea emerged that political and social cognition are deeply intertwined concepts, and understanding one could dramatically improve the understanding of the other (9–12). Researchers in social cognition such as Darren Schrieber, John Jost, and John T Cacioppo were some of the significant proponents of this idea. Schreiber went on further to make evolutionary arguments for the idea that human brains are “built for politics” based on neural studies of humans and primates (13). 

This concept has been dubbed the “Machiavellian Intelligence” or the “social brain” hypothesis after Machiavelli, the rather infamous author of “The Prince” (14). Nicholas Humphrey, a British neuropsychologist, once explained the gist of this argument with a straightforward example. In Defoe’s masterpiece, Robinson Crusoe’s survival on the desert island was technically challenging. But, the really hard problems come from the arrival of Man Friday (15). In essence, social interactions require the most complex form of information processing. The same might have been the primary driving force behind the expanding human behavioral repertoire and evolution of the complex brain we see today. After the initial conception of these ideas, they have been elaborated on by a multitude of researchers from diverse backgrounds in the past years (16). 

With advances in neuroimaging methods like EEG, structural and functional MRI, it has become a lot more accessible to look at brain connections and activity during a large number of tasks (17). Insight into the function of circuits in the brain involved in decision-making, reward processing, and social cognition would not have been possible without these methods. They have made it possible to examine the neural basis of political cognition. Ingrid Haas, a professor of neuropolitics at the University of Nebraska-Lincoln, broadly divides the study of the interaction of the brain and politics into three major categories: (a) the neural basis of political ideology (b) understanding how people evaluate other people in a political context, and lastly (c) neural factors that influence one’s political participation (7). Let’s take a look at them one by one.

2. The Neural Basis of Political Ideology

Social creatures as we are, Humans have a tendency to associate ourselves with categorized communities of people with similar beliefs (18). In the political world, no categorization is considered more influential than the apparent dichotomy of Liberals and Conservatives. Would not understanding its basis be the holy grail of Neuropolitics? But of course, it is one of the most prominent and controversial questions in this field. Many studies have attempted to find biological differences between liberal and conservatives. However, the results are weak and often contradictory.

A difference that has been seen between the two political groups is the relative size and the activity of three brain regions—the ACC, the insula, and the amygdala. Multiple studies have reported that the ACC and insula, areas of the brain involved in detecting and processing conflicting information or beliefs, are larger and more sensitive in Liberals than conservatives (19–22). This increased sensitivity has been further associated with a preference for social equality and social change (22). On the other hand, studies show that conservatives have a larger and more active amygdala, the brain’s emotion and motivation center (19). This has further been linked to a tendency to justify the status quo (23–26). A recent study has found that anterior insular activation is linked to the tendency of conservatives to classify Black and White mixed-race individuals as Black (27). Another study found that the brains of conservatives and liberals have highly polarised responses in the DLPFC in response to discussions of immigration policies and is supported by recent fMRI, EEG and lesion studies. (28–31).

One fascinating study done by the Schreiber Lab in 2013 found that in a task that assesses risk-taking behavior, Liberal-leaning Democrats and Conservative-leaning Republicans seem to perform similarly when it comes to the outcome. However, the activity in their brains as they make decisions is different, with conservatives having more amygdala activity and liberals having more insular activity (32). This led to an exciting hypothesis that even when conservatives and liberals make the same decision, the thought process behind them is dramatically different.  Other studies have tried to link general ideological principles to activity in the brain. For example, studies have found that insular activation is linked to egalitarian beliefs (33), the opposite response is associated with right-wing authoritarianism (34), and greater connectivity between amygdala and BNST relates to economic conservatism (35). 

But at the same time, many attempts to replicate similar results have been met with failures (22,36). Two recent studies found no evidence of a direct link between brain activity and self-reported liberalism/conservatism (37,38). They suggest that there might be a dependence on other social and political factors which may not have been considered earlier such as age and geopolitical context. As most such studies have come out of the US and have not been explored thoroughly in the international context, the concern is valid.

While these results are pretty interesting, one has to be careful with interpretation because it can be a really slippery slope. Being a conservative does not mean you are inherently more emotional; Being a liberal does not make you a genius logician. Most current results in this field are correlations, and the causality hasn’t been tested. What does that mean? It means that understanding the neural basis of liberalism and conservatism is right now a “chicken and egg problem” (39). Neither the structure nor the behavior of the tiny neurons in the brain is absolute; both change with time and experience (40). With short-term experiments and the current technology available, it is impossible to say whether the brain’s innate structure led to a person’s political ideology or whether it is the person’s experiences over their lifetimes that made their brain look and behave that way.

3. Interpersonal Evaluation in a Political Context

The most common question that political neuroscientists face from the public is often a very straightforward question. Can you tell who people will vote for from their brain activity? While the ethics of being able to do that is somewhat questionable, it is a rather intriguing question. In a 2006 study, Spezio and colleagues performed a simple experiment. They simulated a ‘mini election’ where the participants would be presented with just the images of two unfamiliar politicians in rapid succession and asked to vote for one of them (41). When looking at the candidate they did not vote for, the participant’s ACC and insula showed more significant activity associated with a feeling of a personal threat. Another study suggested that looking at preferred candidates triggers activity in the brain’s reward processing center, the ventral striatum, indicating that people see them as ‘rewarding’ (42).

Now the big question is: Are these rapid, reflexive responses actually reflective of the outcome of actual elections? There is evidence to suggest so (43,44). A study published in PNAS showed that participant’s beliefs after rapid exposure to images of US gubernatorial candidates were enough to predict the actual election outcomes (43). This prediction was actually better than when the participants were allowed to think and decide. Surprising, isn’t it? Guess what’s more. One would expect that they would need to have the conscious memory of the candidates’ policies to choose a candidate aligned with their own ideologies, right? Researchers have found that patients suffering from damage in the brain’s memory centers which caused anterograde amnesia could choose a candidate with the same political-leaning as them, despite severe memory impairment (45). They did this as accurately as neurologically unaffected people. This suggested that the conscious memory of policy might be inconsequential to voting choices. 

If that is so, what is the driving factor for voting choices? Many political scientists have suggested that partisanship can be one such factor. Some neurological studies have found that exposure to a candidate from a different party triggers activity in the brain’s circuits that have been associated with cognitive control of negative emotions (42,46). This has been suggested to provide a possible neural basis for the “us vs. them” mentality. Another fascinating experiment discovered that when participants are faced with information that is incongruent with their own beliefs, people who are more resistant to the counterarguments show more robust activation in their emotion centers (47–49). This suggests that the political decisions of a person might be constrained by their emotional response.

Often researchers in this field have a tendency to focus on the politics of the state, i.e., the politics concerning voting, elections, and government policies. However, neuropolitics can also provide us further insight into understanding other interpersonal, political evaluations such as racial and ethnic attitudes (50,51). In fact, these studies were at the forefront of the field when the transition from cognitive neuroscience to social/political cognition first began (52). 

Early studies by Elizabeth Phelps and Matthew Leiberman explored the underlying neural substrates that are involved in the evaluation of Black individuals by Caucasian participants (53,54). They found that amygdala activation correlated with the unconscious (implicit) but not the conscious (explicit) racial attitudes. Another study showed that exposure to Black faces in a pro-White biased individual has higher activation of the ACC and DLPFC than a person with less pro-White bias (55). ACC and DLPFC are both centers for conflict detection and modulation. This suggests a conflict of conscious egalitarian principles and subconscious pro-White biases. Building on this further, it was shown that people who prefer racial equality without external motivation had a more robust response in the ACC compared to their counterparts (56,57). 

A prevalent racial stereotype is that people find individuals from a different race to look the same.  Studies of the Fusiform Gyrus have shown that the FFA, a region implicated in face recognition, seems to respond stronger to faces of the same race than other races (58,59). This likely results in the homogenization of other race’s individual identity. Together, the FFA, Amygdala, ACC show how diverse racial attitudes might be reflected in the brain (60). It still remains to be discovered how the variation between the structure and behavior of these brain regions might influence actual decision-making in the real world. These results are not limited to just racial identity.

Chimpanzees often have large communal conflicts and annex territory driven by a biological drive towards a tribal organization (14). Famous author Robert Sapolsky has hypothesized that humans share this innate tendency to form strong associations with people close to them (61). This simultaneously drives conflict against the out-groups, possibly because of the activation of the same pathways as race. He then builds this idea to propose a neural theory of nationalism (62). Some other recent studies have discovered other brain regions, such as the PCC and OFC, where a greater cell density is associated with nationalism (63). This was also linked to less compassion and a feeling of superiority over others. The study even managed to distinguish between neural correlates of patriotism and nationalism. It is again important to note that almost all of these results are correlational and do not prove a causal effect. They are still educated guesses about how things might be. 

4. The Drive behind Political Participation

Research in neuropolitics has also tried answering an even more fundamental question—why do people even choose to participate in political decision-making? (7) Theories of social cognition like Schieber’s theory of a political brain (discussed earlier) are but a few of the attempts to answer this question (13).  Some studies even have tried and found genetic correlates of voter turnout (64,65). While these studies themselves might have many caveats, the number of citations they have received gives an idea about the interest in this question. 

Often asking such a broad ‘why’ question is a vast undertaking requiring insight that is not available yet. In such a scenario, maybe it is better to focus on a more specific question: What drives a person to vote during elections? Psychologists have long proposed that if the process of voting is rewarding to the voter, it increases the likelihood that they will end up voting (66). Is that really true? The answer to this question is likely linked to political interest. A study showed that people with a higher interest in politics have greater activation of the brains’ reward and emotion centers in response to political statements they agree with (67). This suggested that for some people, political participation itself might be a source of utility. 

Not all people vote with the same motives. Another study has found that the nature of the reward to the voter might also vary between people. They found that people with less altruistic tendencies have an activation of the reward pathway linked to immediate utility rather than a long-term expectation of utility under an uncertain scenario (68). There are many other ways of political participation such as protesting, making political donations, and even becoming a politician, the neural basis of which are yet to be explored. 

5. Conclusion

Neuropolitics is fascinating indeed, but with the excitement and grand nature of the questions asked, there comes a tendency to over-interpret results, make logical jumps without enough justification or evidence, and suggest causal relationships with raw correlational data. Sometimes the interpretations have, in fact, gone too far, triggering neuroscientists to distance themselves from the studies (69,70). Critics have further pointed out that “Neuroscience is just not there yet” (71). Proving causality is still a big hurdle in human studies (72,73). Some new studies have even suggested that functional MRI might not be as useful for understanding individual-level differences as previously thought (74). In essence, we do not yet have the technology or the intellectual capital to thoroughly understand the basis of social cognition. However, none of these setbacks mean that it is impossible to answer these questions or that we should give up.

We must recognize that neuroscience has made enormous progress in less than a century. Just 70 years ago, Hodkin and Huxley were still sticking electrodes into squids and figuring out how neurons work (75). Now, we have reached a point where we have sophisticated methods of observing, perturbing, and modeling nervous systems at a scale that would have been almost unimaginable then. With that in mind, who knows what we will be capable of doing 50 years from now?

Neuropolitics has a lot more to offer us. Like Schrieber wrote in a recent review, “the ‘friendship’ between neuroscience and politics is still in the acquaintance stage” (52). I would like to conclude this essay with a quote from Robert Heinlein that explains the potential this field has in one sentence: “Everything is theoretically impossible until it is done.”

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