Biology and political orientation
One 2011 study, for instance, found that subjects with right-wing (or conservative in the United States) political views have larger amygdalae,[2] areas of the brain associated with emotional responses such as fear, anxiety, and aggression.
[3][4] However, there is considerable disagreement among experts as to whether biological explanations for differences in political orientation are methodologically sound, and many studies which purport to demonstrate a connection have not been replicated.
[2] The researchers performed MRI scans on the brains of 90 volunteer students who had indicated their political orientation on a five-point scale ranging from "very liberal" to "very conservative".
[2][7] Students who reported more conservative political views were found to have larger amygdala,[2] a structure in the temporal lobes whose primary function is in the formation, consolidation and processing of memory, as well as positive and negative conditioning (emotional learning).
[20][21] The anterior cingulate cortex becomes active in situations of uncertainty,[22] and is postulated to play a role in error detection, such as the monitoring and processing of conflicting stimuli or information.
Conservatives are more likely to report larger social networks, greater happiness and self-esteem than liberals, are more reactive to perceived threats and more likely to interpret ambiguous facial expressions as threatening.
[41] A 2018 study of 15,001 participants in the United States looking at levels of cognitive reflection (the tendency to favour analytic reasoning over instinctive or "gut" responses) found that those who voted for Donald Trump in the 2016 US presidential election had lower levels of cognitive reflection than Hillary Clinton voters or third-party voters.
Holding right-wing views was also associated with a stronger startle reflex as measured by strength of eyeblink in response to unexpected noise.
[44][45] In an fMRI study published in Social Neuroscience, three different patterns of brain activation were found to correlate with individualism, conservatism, and radicalism.
[51][52] A twin study in 2005 by Alford et al. examined the attitudes regarding 28 different political issues such as capitalism, unions, X-rated movies, abortion, school prayer, divorce, property taxes, and the draft.
[53][54] However, Jonathan Kaplan argued that the role of individual genes is often extremely small due to many human physical traits being polygenic and may be overstated,[55] observing that the study by Alford et al. made a case for the role of the 5-HTTLPR region being involved in numerous psychological and personality traits, yet Border et al. (2019) found that multiple associations with 5-HTTLPR were spurious and underpowered.
[56] Jost et al. wrote in a 2011 review that "Many studies involving quite diverse samples and methods suggest that political and religious views reflect a reasonably strong genetic basis, but this does not mean that ideological proclivities are unaffected by personal experiences or environmental factors.
"[1] In 2014, a study was performed on genomic data from 12,000 twin pairs from Australia, the USA, Denmark, Sweden and Hungary to examine genetic influences on political ideology.
The study's genome-wide association analysis did not provide any definitive evidence of a specific genetic marker related to ideology.
[57] "A Genome-Wide Analysis of Liberal and Conservative Political Attitudes" by Peter K. Hatemi et al. traces DNA research involving 13,000 subjects.
Evan Charney publishing in Perspectives on Politics argues that Alford et al.'s research is methodologically flawed, their data does not support their conclusions, and the creation of 'liberal' and 'conservative' 'phenotypes' is untenable.
