Differences between conservative and liberal brain

According to Ryota Kanai's study, conservatives have larger amygdalas (shown in red)

Kanai's study shows liberals have larger anterior cingulate cortexes (shown in red)

Several studies have sought to find differences between the structure or functions of people's brains who identify as conservatives and liberals. This distinction is still fairly unclear, according to studies, and gives no explanation for socially liberal, fiscally conservative or apolitical people.^[1]

Structural differences

Nature Neuroscience in 2007 reported a study^[2] by scientists at New York University and UCLA that showed that political orientation is related to differences in how the brain processes information. According to UCLA neurologist Dr. Marco Iacoboni, the study showed "there are two cognitive styles -- a liberal style and a conservative style."^[3] The article "Neurocognitive correlates of liberalism and conservatism"^[2] published in Nature Neuroscience "found that greater liberalism was associated with stronger conflict-related anterior cingulate activity, suggesting greater neurocognitive sensitivity to cues for altering a habitual response pattern."^[2]

According to a 2011 study^[4] by cognitive neuroscientist Ryota Kanai's group^[5] at University College London published in Current Biology, people with different political views have different brain structures.^[6] The scientists performed MRI scans on 90 volunteer young adult people's brains.^[7] According to ABC, "Scans revealed that the liberal students tended to have a larger region of the brain that processes conflicting information. That, say the authors, might make for tolerance to uncertainty in more liberal views. The conservatives tended to have a larger part of the brain that processes fear and identifies threats. They might be more inclined to integrate conservative views into their politics." The results of the study showed that conservatives had a larger amygdala,^[8] an almond-shaped structure of brain that processing and memory of emotional reactions.^[9] Liberals had increased grey matter in the anterior cingulate cortex,^[8] a comma-shaped structure of the brain that plays a role in a wide variety of autonomic functions, such as regulating blood pressure and heart rate, as well as rational cognitive functions, such as reward anticipation, decision-making, empathy^[10] and emotion.^[11][12] As a result of these structural differences, liberals may be more efficient at managing conflicting information, while conservatives may be more efficient at recognizing threats.^[7][13][14] The researchers concluded, "It's very unlikely that actual political orientation is directly encoded in these brain regions." Kanai also warned: "More work is needed to determine how these brain structures mediate the formation of political attitude."^[7][14]

In an earlier fMRI study published in Social Neuroscience, three different patterns of brain activation were found to correlate with individualism, conservatism, and radicalism.^[15] In general, fMRI responses in several portions of the brain have been linked to viewing of the faces of well-known politicians.^[16] Others believe that determining political affiliation from fMRI data is overreaching.^[17]

Amygdala size differences

According to some studies, the amygdala is larger in males than in females.^[18]

Enlargement of the amygdala has been associated with bipolar disorder.^[19][20]

There is evidence that the structure of the amygdala plays some role in Autism spectrum disorders, but in terms of the size of the amygdala evidence is conflicting, with some studies showing a positive correlation between amygdala size and autism and others showing a negative correlation.^[21]

Reduced amygdala size is associated with psychopathy.^[22]

The amygdala has been associated with discrimination of faces by race, with it showing "greater responses to unfamiliar than familiar neutral face stimuli."^[23]

Activity in the amygdala has also been associated with interest in politics in general.^[24]

Anterior cingulate cortex size differences

Autism disorders have been associated with decreased activity in the anterior cingulate cortex.^[25]

Size of the cortex has been associated with higher IQ and faster reaction time.^[26]

A study showed that boys with callous-unemotional conduct problems, thought to be antecedents to psychopathy, exhibited an increased amount of gray matter in the anterior cingulate cortex.^[27]

Political genome studies

A Genome-Wide Analysis of Liberal and Conservative Political Attitudes by Peter K. Hatemi et al traces DNA resaerch involving 13,000 subjects. The study identifies several genes potentially connected with political positions.^[28]

Functional assays

According to the ASA, IQ data from the "Add Health" survey averaged 106 for adolescents identifying as "very liberal", versus 95 for those calling themselves "very conservative".^{[29][30][31][32][33][34][35]} An unrelated study in 2009 found that among students applying to U.S. universities, conservatism correlated negatively with SAT, Vocabulary, and Analogy test scores though there was a greater correlation with economic differences.^[36]

In a survey of the perceived severity of moral transgressions, conservatives were more affected by the taste of a bitter drink than liberals.^[37] "...taste perception significantly affected moral judgments, such that physical disgust (induced via a bitter taste) elicited feelings of moral disgust. Further, this effect was more pronounced in participants with politically conservative views".

Persistance of patterns

A study by scientists at New York University and the University of California, Los Angeles found differences in how self-described liberal and conservative research participants responded to changes in patterns.^[38][39] Participants were asked to tap a keyboard when the letter 'M' appeared on a computer monitor and to refrain from tapping when they saw a 'W.' The letter 'M' appeared four times more frequently than W, conditioning participants to press the keyboard on almost every trial. Liberal participants made fewer mistakes than conservatives when they saw the rare W, indicating to the researchers that these participants were better able to accept changes or conflicts in established patterns.

The participants were also wired to an electroencephalograph that recorded activity in their anterior cingulate cortex, the part of the brain that detects conflicts between a habitual tendency and a more appropriate response. Liberals were significantly more likely than conservatives to show activity in the brain circuits that deal with conflicts during the experiment, and this correlated with their greater accuracy in the test.

References

1. ^ Liberal or Conservative? Research finds a difference in the brain | God Discussion
2. ^ ^{a b c} David M Amodio, John T Jost, Sarah L Master & Cindy M Yee, Neurocognitive correlates of liberalism and conservatism, Nature Neuroscience. Cited by 69 other studies
3. ^ Study finds left-wing brain, right-wing brain - latimes.com
4. ^ R. Kanai et al. (2011-04-05). "Political Orientations Are Correlated with Brain Structure in Young Adults". Curr Biol 21 (8): 677–80. doi:10.1016/j.cub.2011.03.017. PMID 21474316. 
5. ^ Is Your Brain Liberal or Conservative? - FoxNews.com
6. ^ Left brain, right brain: researchers link neurology to political orientation
7. ^ ^{a b c} Liberal vs. Conservative: Does the Difference Lie in the Brain? – TIME Healthland
8. ^ ^{a b} Political Orientations Are Correlated with Brain Structure in Young Adults Ryota Kanai, Tom Feilden, Colin Firth and Geraint Rees. Science Direct
9. ^ Amunts K, Kedo O, Kindler M, Pieperhoff P, Mohlberg H, Shah N, Habel U, Schneider F, Zilles K (2005). "Cytoarchitectonic mapping of the human amygdala, hippocampal region and entorhinal cortex: intersubject variability and probability maps". Anat Embryol (Berl) 210 (5-6): 343–52. doi:10.1007/s00429-005-0025-5. PMID 16208455. 
10. ^ Zimbardo begins Heroic Imagination Project, Stanford Daily, Jan 7, 2011
11. ^ Decety, J., & Jackson, P.L. (2004). The functional architecture of human empathy. Behavioral and Cognitive Neuroscience Reviews. 3. pp. 71–100. 
12. ^ Jackson P.L., Brunet E., Meltzoff A.N., Decety J. (2006). "Empathy examined through the neural mechanisms involved in imagining how I feel versus how you feel pain: An event-related fMRI study". Neuropsychologia 44: 752–61. doi:10.1016/j.neuropsychologia.2005.07.015. 
13. ^ The liberal brain? Scans show liberals and conservatives have different brain structures - New York Daily News
14. ^ ^{a b} Politics on the Brain: Scans Show Whether You Lean Left or Right | Political Psychology | Liberals & Conservatives | LiveScience
15. ^ Zamboni G, Gozzi M, Krueger F, Duhamel JR, Sirigu A, Grafman J (2009). Individualism, conservatism, and radicalism as criteria for processing political beliefs: a parametric fMRI study. 4. pp. 367–83. doi:10.1080/17470910902860308. PMID 19562629.  Zamboni G, Gozzi M, Krueger F, Duhamel JR, Sirigu A, Jordan Grafman. National Institutes of Health, Bethesda, MD, USA
16. ^ Kristine Knudson et al. (2006-03). Politics on the Brain: An fMRI Investigation. PubMed preprint (Soc Neurosci). PMC 1828689. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1828689. 
17. ^ Aue T, Lavelle LA, Cacioppo JT (July 2009). Great expectations: what can fMRI research tell us about psychological phenomena?. 73. pp. 10–6. doi:10.1016/j.ijpsycho.2008.12.017. PMID 19232374. 
18. ^ Sex differences: summarizing more than a century of scientific research Lee Ellis, CRC Press, 2008 972 pages page 62
19. ^ Bipolar Disorder: Clinical and Neurobiological Foundations Lakshmi N. Yatham, John Wiley and Sons, 2010 522 pages, page 125
20. ^ Understanding Bipolar Disorder: A Developmental Psychopathology Perspective David J. Miklowitz, Dante Cicchetti, Guilford Press, 2010 572 pages, page 265
21. ^ Autism spectrum disorders: psychological theory and research Dermot M. Bowler, John Wiley and Sons, 2007 308 pages, page 172
22. ^ Localization of Deformations Within the Amygdala in Individuals With Psychopathy Yaling Yang, Adrian Raine, Katherine L. Narr, Patrick Colletti, MD, Arthur W. Toga, Arch Gen Psychiatry. 2009;66(9):986-994
23. ^ Differential response in the human amygdala to racial outgroup vs ingroup face stimuli Allen J. Hart,1,CA Paul J. Whalen,2 Lisa M. Shin,3 Sean C. McInerney, HaÊkan Fischer4 and Scott L. Rauch; BRAIN IMAGING NEUROREPORT 0959-4965 page 3
24. ^ Interest in politics modulates neural activity in the amygdala and ventral striatum† Marta Gozzi1, Giovanna Zamboni1, Frank Krueger, Jordan Grafman, Human Brain Mapping Volume 31, Issue 11, pages 1763–1771, November 2010 "In addition, individuals interested in politics showed greater activation in the amygdala and the ventral striatum (ventral putamen) relative to individuals uninterested in politics when reading political opinions in accordance with their own views. This study shows that having an interest in politics elicits activations in emotion- and reward-related brain areas even when simply agreeing with written political opinions."
25. ^ Researching the Autism Spectrum: Contemporary Perspectives By Ilona Roth, Payam Rezaie, Cambridge University Press, 2011 - Medical - 418 pages page 127
26. ^ Handbook of developmental cognitive neuroscience By Monica Luciana, MIT Press, 2001 - Medical - 685 pages page 139
27. ^ Size matters: Increased grey matter in boys with conduct problems and callous–unemotional traits Stéphane A. De Brito1, Andrea Mechelli, Marko Wilke, Kristin R. Laurens, Alice P. Jones, Gareth J. Barker, Sheilagh Hodgins, Essi Viding, Brain (2009) 132 (4): 843-852. doi: 10.1093/brain/awp011
28. ^ Genome-Wide Analysis of Liberal and Conservative Political Attitudes Peter K. Hatemi United States Studies Centre, University of Sydney and Queensland Institute of Medical Research, Nathan A. Gillespie Virginia Institute for Psychiatric and Behavioral Genetics, Lindon J. Eaves Virginia Institute for Psychiatric and Behavioral Genetics, Brion S. Maher Virginia Institute for Psychiatric and Behavioral Genetics, Bradley T. Webb Virginia Institute for Psychiatric and Behavioral Genetics, Andrew C. Heath Washington University St. Louis, Sarah E. Medland Queensland Institute of Medical Research, David C. Smyth Queensland Institute of Medical Research, Harry N. Beeby Queensland Institute of Medical Research, Scott D. Gordon Queensland Institute of Medical Research, Grant W. Montgomery Queensland Institute of Medical Research, Ghu Zhu Queensland Institute of Medical Research, Enda M. Byrne Queensland Institute of Medical Research, Nicholas G. Martin Queensland Institute of Medical Research, The Journal of Politics, Vol. 73, No. 1, January 2011, Pp. 1–15 ISSN 0022-3816 "The under-standing that we cannot yet accurately map howgenes influence brain processes and biological mech-anisms which in turn interact with our upbringing,social life, personal experience, the weather, diet, etc,to somehow be expressed in part as a Conservative-Liberal orientation, is the exact reason that genome-wide analyses are valuable and necessary for politicalscience.
29. ^ "Intelligent People Have "Unnatural" Preferences and Values That Are Novel in Human Evolutionary History". American Sociological Association press release. 2010-02-23. http://www.asanet.org/press/20100223/Evolution_and_Intelligence.cfm. 
30. ^ Satoshi Kanazawa (2010). "Why Liberals and Atheists Are More Intelligent". Social Psychology Quarterly. doi:10.1177/0190272510361602. http://spq.sagepub.com/cgi/content/abstract/0190272510361602v1. 
31. ^ "Liberals and Atheists Smarter? Intelligent People Have Values Novel in Human Evolutionary History, Study Finds". ScienceDaily. 2010-02-24. http://www.sciencedaily.com/releases/2010/02/100224132655.htm. 
32. ^ Elizabeth Landau (2010-02-26). "Liberalism, atheism, male sexual exclusivity linked to IQ". CNN. http://www.cnn.com/2010/HEALTH/02/26/liberals.atheists.sex.intelligence/index.html?section=cnn_latest. 
33. ^ John Cloud (2010-02-26). "Study: Are Liberals Smarter Than Conservatives?". Time Magazine. http://www.time.com/time/health/article/0,8599,1968042,00.html?xid=rss-topstories. 
34. ^ "Higher IQ linked to liberalism, atheism". UPI. 2010-03-02. http://www.upi.com/Health_News/2010/03/02/Higher-IQ-linked-to-liberalism-atheism/UPI-68381267513202/. 
35. ^ Nicole Baute (2010-03-01). "Are liberals and atheists smarter? Psychologist links teen IQ levels with adult views on religion, politics and family". Toronto Star. http://www.thestar.com/living/article/773018--are-liberals-and-atheists-smarter. 
36. ^ Larry Stankov (2009-05). "Conservatism and cognitive ability". Intelligence 37 (3): 294–304. doi:10.1016/j.intell.2008.12.007. 
37. ^ Eskine KJ, Kacinik NA, Prinz JJ (March 2011). A bad taste in the mouth: gustatory disgust influences moral judgment. 22. pp. 295–9. doi:10.1177/0956797611398497. PMID 21307274. 
38. ^ "Brains of Liberals, Conservatives May Work Differently". Psych Central. 2007-10-20. http://psychcentral.com/news/2007/09/10/brains-of-liberals-conservatives-may-work-differently/1691.html. 
39. ^ "Study finds left-wing brain, right-wing brain". Los Angeles Times. 2007-09-10. http://www.latimes.com/news/obituaries/la-sci-politics10sep10,0,2687256.story. 

External links

• healthland.time.com
• abcnews.go.com