Liberals Are Neurotic and Conservatives Are Antisocial

An awful lot of cyberink has been spilled over the liberal-conservative EEG study published online in Nature Neuroscience a few days ago. The Neurocritic is not an expert in social psychology or personality, so to be fair in the sequel to The Error of Prognosticating Political View by Brain Wave, I decided to read [skim] the 2003 paper by Jost and colleagues, Political Conservatism as Motivated Social Cognition (PDF here). An obvious question for the uninitiated is whether there is any truth to the title of this post, other than the inference I made based on the error-related negativity literature: ¹

Liberals showed larger ERN waves than conservatives when mistakenly responding on No-Go trials. However, so do individuals with clinical diagnoses such as obsessive-compulsive disorder (Gehring et al., 2000) or major depressive disorder (Chiu & Deldin, 2007).

On the other hand, individuals with schizophrenia (Mathalon et al., 2002) or psychopathy (Munro et al., 2007) show smaller ERN waves than control participants. These findings extend to the normal population, i.e., people who do not fit the criteria for a clinical diagnosis, but who score higher or lower on certain traits. For example, people who score high on negative affect have bigger ERNs (Hajcak et al., 2004), while individuals with "externalizing psychopathology" have smaller ERNs (Hall et al., 2007). Does this mean that liberals are neurotic and conservatives are antisocial? Since these were not assessed along with political orientation, we can only hazard a guess...

Actually, we may not need to hazard a guess, because such measures may have been already obtained from these subjects, as stated in the Supplementary Methods:

A measure of political attitudes was embedded in a larger set of personality and attitudes surveys completed at the every [sic] beginning of the experimental session.

So a paper about neurotic liberals with large ERNs and antisocial conservatives with small ERNs may yet appear in a journal near you. This begs the question,

Perhaps there were any other correlations? I wonder what the odds were of a stastically [sic] significant finding given the number of personality and attitude surveys.

But back to the 2003 paper. I do remember that it raised a big stink in the media at the time, not surprising given a press release like this:

Disparate conservatives share a resistance to change and acceptance of inequality, the authors said. Hitler, Mussolini, and former President Ronald Reagan were individuals, but all were right-wing conservatives because they preached a return to an idealized past and condoned inequality in some form. Talk host Rush Limbaugh can be described the same way, the authors commented in a published reply to the article.

Here's the abstract of the paper (Jost et al., 2003), which really is all about conservatism: ²

Analyzing political conservatism as motivated social cognition integrates theories of personality (authoritarianism, dogmatism–intolerance of ambiguity), epistemic and existential needs (for closure, regulatory focus, terror management), and ideological rationalization (social dominance, system justification). A meta-analysis (88 samples, 12 countries, 22,818 cases) confirms that several psychological variables predict political conservatism: death anxiety (weighted mean r=
.50); system instability (.47); dogmatism–intolerance of ambiguity (.34); openness to experience (–.32); uncertainty tolerance (–.27); needs for order, structure, and closure (.26); integrative complexity (–.20); fear of threat and loss (.18); and self-esteem (–.09). The core ideology of conservatism stresses resistance to change and justification of inequality and is motivated by needs that vary situationally and dispositionally to manage uncertainty and threat.

OK then, "resistance to change" appears to extend to a lowered ability to inhibit habitual responding and a diminished brain response to such mistakes (Amodio et al., 2007). It's still not clear to me, however, how brain systems responsible for personality constructs like intolerance of ambiguity and needs for order, structure, and closure overlap with brain systems responsible for not pressing a key to a letter presented 20% of the time.

Now back to the 2007 NN article again. I hate to belabor the point, but it's only fair to examine the paper on its merits, not on the ideologies of the authors, no matter how much I might agree with them. But really, this blog comment sums it up:

It is useless to try to infer anything from this study. The experimenter has 26 liberals and 7 conservatives. Not exactly equal sample sizes, and not a big enough sample of conservatives to gain any inference about the range of responses here, even if you buy into the non-sequiter introduction set out by the authors. [NOTE: the following objections were addressed by the first author.] A thought experiment: would the correlation hold up if the two biggest outliers were excluded. Doesn't look like it. No mention of possible sex differences etc. usually discussed in these papers. The authors fail to address these confounds even in the supplementary info. A sad commentary on the state of science when a journal with this level of impact publishes a study of this low quality.

Posted by: John Broussard | September 11, 2007 6:48 PM

Huh. So this would imply that the brain wave data shown in Fig 1b of Amodio et al. (2007) were averages from 7 conservatives and ~26 liberals!

And a very important bit of data -- mean accuracy rates for conservatives and liberals -- didn't appear anywhere in the paper [someone correct me if I'm wrong], but was published in this newspaper article:

In the 400 easy trials, just about everyone got it right.

But in the 100 tough trials, when students saw the letter that meant they shouldn't press a button, self-described conservatives pressed the button anyway nearly half the time - an error rate of 44 out of 100.

Liberals fumbled about a third of the time, with an error rate of 34 out of 100.

Neurophilosophy reported slightly different figures [not sure where he got them]:

It was found that those who considered themselves to be conservatives made more response errors when upon presentatin of the infrequent letters than those who considered themselves as liberals (respectively, 47% and 37% of the time).

Have any of you ever published papers in less prestigious journals without including mean accuracy and reaction time values for your comparison populations?? There was absolutely no information about RTs at all, so we don't know whether there was a speed-accuracy trade-off in the conservatives (a "reckless" and disinhibited response style) or whether they were "conscientious" (RT comparable to [or slower than] liberals), but just couldn't stop themselves from pressing the key on No-Go trials.

Enough already with the ranting.

Peace. Shana Tova.


Footnotes

¹ See previous post for a list of those references.

² This paper doesn't discuss the psychological variables that predict liberalism, so in the end we don't know if liberals are neurotic; the incidence of antisocial traits in conservatives was not reported.

References

Amodio DM, Jost JT, Master SL, Yee CM. (2007). Neurocognitive correlates of liberalism and conservatism. Nature Neurosci. Published online 9 September 2007.

Jost JT, Glaser J, Kruglanski AW, Sulloway FJ. (2003). Political conservatism as motivated social cognition. Psychol Bull. 129:339-75.

Meet The Neuro Doubters

Meet the “neuro doubters.” The neuro doubter may like neuroscience but does not like what he or she considers its bastardization by glib, sometimes ill-informed, popularizers.

A gaggle of energetic and amusing, mostly anonymous, neuroscience bloggers — including Neurocritic, Neuroskeptic, Neurobonkers and Mind Hacks — now regularly point out the lapses and folly contained in mainstream neuroscientific discourse. This group, for example, slammed a recent Newsweek article in which a neurosurgeon claimed to have discovered that “heaven is real” after his cortex “shut down.” Such journalism, these critics contend, is “shoddy,” nothing more than “simplified pop.” Additionally, publications from The Guardian to the New Statesman have published pieces blasting popular neuroscience-dependent writers like Jonah Lehrer and Malcolm Gladwell. The Oxford neuropsychologist Dorothy Bishop’s scolding lecture on the science of bad neuroscience was an online sensation last summer.

from Neuroscience: Under Attack
By ALISSA QUART
Published: November 23, 2012

Thanks to author Alissa Quart for mentioning The Neurocritic in her New York Times Opinion piece, along Neuroskeptic, Neurobonkers, Mind Hacks, and Dorothy Bishop.¹ Ms. Quart opens her salvo against bad neuroscience, and its misrepresentation in the popular press, with an easy target: Naomi Wolf and her Vagina: A New Biography. Several of the Neuro Doubters wrote popular, well-received posts that were critical of Ms. Wolf's grasp of neuroscience.²

Another specific target is Chris Mooney's book, The Republican Brain. I have not read this book (or any excerpts) and therefore cannot offer an opinion on it. However, the "Political Brain" has been the topic of flawed studies, bad press releases, and even an ill-conceived op-ed in a famous newspaper, so I'll use this as an example of the varieties of Neuro Doubt.

Flawed studies - One study concluded that Liberals Are Neurotic and Conservatives Are Antisocial, another that Conservatives Are Neurotic and Liberals Are Antisocial. OR perhaps Atheists Are Neurotic and Religious Zealots Are Antisocial.

Bad press releases - The title of this spoof press release says it all: New research provides fresh evidence that bogus press releases may depend largely on our biological make-up. This well-deserved parody covered an unpublished study on the purported differences between the brains of Democrats vs. Republicans. The timing? Right before Election Day. It was a university press office's attempt at positive publicity that backfired, in my view.

Ill-conceived op-eds (in the New York Times) - This is Your Brain on Politics presented the results of a neuroimaging study on swing voters in the Opinion Pages of the NYT (rather than in a professional journal).  A peer-review drubbing of sorts took place in a Letter to the Editor: Politics and the Brain.


The Seductive Allure of Neuroscience Explanations



One problem with the ubiquity of pop neuroscience is that pretty colorful pictures of brains can sway people to believe that some outlandish statement is true. This was shown by McCabe and Castel (2008) in "Seeing is believing: the effect of brain images on judgments of scientific reasoning." Another aptly-titled article, "The seductive allure of neuroscience explanations," provided verbal descriptions of brain scans to convince people that a bogus scientific argument was valid (Weisberg et al., 2008).


The Rise of Neurobollocks and Neuromania

It's actually very trendy these days to bash neuroscience. In fact it's so fashionable that I've considered starting a backlash against the backlash - The Neurocomplimenter (e.g., "That was a fantastic study! Good show!"). I am, after all, a working neuroscientist so I don't want to see my field go down in flames. But are we at risk for that? Is neuroscience really under attack? The most potent form of attack would be financial. I haven't noticed a specific decrease in federal funding for neuroscience; the downturn in the U.S. has affected research in general. What I have noticed is an increase in anti-neuroscientism punditry:

An intellectual pestilence is upon us. Shop shelves groan with books purporting to explain, through snazzy brain-imaging studies, not only how thoughts and emotions function, but how politics and religion work, and what the correct answers are to age-old philosophical controversies. The dazzling real achievements of brain research are routinely pressed into service for questions they were never designed to answer. This is the plague of neuroscientism – aka neurobabble, neurobollocks, or neurotrash – and it’s everywhere.

My response to such alarmist hype was to call it the Journomarketing of Neurobollocks. Yes, it's true that the neurorelationship self-help cottage industry (for instance) tries to sell books by claiming to be scientific. And that any knowledge of the brain is completely unnecessary for take-home messages that include the benefits of mindfulness meditation and tips for attaining goals.

According to Quart:

Neuroscience has joined company with other totalizing worldviews — Marxism, Freudianism, critical theory — that have been victim to overuse and misapplication. 

[NOTE: I never suspected my discipline was self-aware enough to have a totalizing worldview...]

But interestingly, I would guess that critical theorists are among those leading the charge against neuroscientism in academia, in a repudiation of overly biological and reductionist explanations for human behavior. ³


Footnotes

¹ Thanks also to Time writer Maia Szalavitz, who recommended my blog to Ms. Quart.

² And her odd declarations, such as "dopamine is the ultimate feminist chemical in the female brain." See Feminist Dopamine, Conscious Vaginas, and the Goddess Array, Naomi Wolf's "Vagina" is full of bad science about the brain, and Mind Hacks author Dr. Vaughan Bell's pre-Vagina post on Naomi Wolf, porn and the misuse of dopamine. And don't miss the posts by our kindred science writers.

³ See Neuroetiquette and Neuroculture and Post-Antipsychiatry.

Atheists Are Neurotic and Religious Zealots Are Antisocial

"Religion is the Xanax of the people" (Inzlicht et al., 2009).

The clever quote above is from the latest paper to garner the _______ Are Neurotic and _______ Are Antisocial style of sensationalistic headline, a study that claims to reveal the Neural Markers of Religious Conviction. I was all prepared to hate the paper, but the authors are not unreasonable in their hypotheses and predictions.

But first, a little background. A year and a half ago, Amodio et al. (2007) published an eye-catching article in Nature Neuroscience that reported on supposed "hard-wired" differences in the brains of liberals and conservatives. The typical media feeding frenzy ensued, complete with simplistic headlines (and some interpretive stretching on the part of the authors).

As we recounted in The Error of Prognosticating Political View by Brain Wave,¹ there were:

...overblown quotes:

Are We Predisposed to Political Beliefs?

. . .

"In the past, people thought that…[political leanings were]…all environmentally influenced, a combination of biological dispositions as well as cultural shaping," says David Amodio, an assistant professor of psychology at New York University. However, a new study, led by Amodio, indicates that political bent "is not just a choice people have, but it seems to be linked to fundamental differences in the way people process information."

And the baseless assertion of innate differences between the brains of liberals and conservatives:

brain neurons of liberals and conservatives fire differently [sic] when confronted with tough choices, suggesting that some political divides may be hard-wired, according a study released Sunday.

That study is quite relevant here because Inzlicht and colleagues used the same neural measure as Amodio et al. (2007). Both experiments used EEG recordings, specifically event-related potentials. The ERP brain waves reflect electrophysiological activity recorded remotely from the scalp. While it's great for determining the temporal parameters of neural activity, it's not so great at determining where the activity is located in the brain.

The brain wave of interest is the error-related negativity (ERN), recorded at the time that people make mistakes in a task:

The ERN is evident as a large negative polarity peak in the event-related brain potential waveform that occurs when people make errors in reaction time tasks. It begins at the moment of the error and reaches a maximum about 100 milliseconds later (see Gehring et al., 1993, PDF). It is largest at fronto-central scalp locations and appears to come from an area of the brain called the anterior cingulate cortex...

There is some disagreement about what the ERN wave represents: a direct response to the mismatch between the intended action and the actual one, a more generic response to conflict in general, or an emotional response to f***ing up. And because EEG is recorded from the scalp, one cannot say for certain that the anterior cingulate is the sole origin.

What does all this have to do with that old time religion? Inzlicht et al. review the neuropsychology of anxiety and how religion serves to quell the angst:

XANAX OF THE PEOPLE

One of religion’s primary functions may be to help people cope with existential uncertainty. In the words of St. Ambrose (ca. 390 AD), ‘‘amid the agitations of the world, the Church remains unmoved; the waves cannot shake her. While around her everything is in a horrible chaos, she offers to all the shipwrecked a tranquil port where they will find safety’’ (quoted in Durant, 1950, p. 79). Religion provides people with a meaning system that helps them navigate through and understand an infinitely complex and uncertain world (Peterson, 1999). It meets the fundamental need to comprehend the deepest problems of existence. Scholars of religion, from James (1902/2002) to Durkheim (1912/1954), have noted that religion imbues life with motivation, purpose, and meaning.

What does anxiety have to do with the ERN wave?? It's larger in those with anxiety disorders, as Hajcak et al. (2004) have noted. And the hypothesis of the present paper?

How is it that religion can bring about both peace of mind and zealous conviction? We suggest that religious conviction buffers against anxiety by providing relief from the experience of uncertainty and error, and in so doing, strengthening convictions and narrowing attention away from inconsistencies. We hypothesize that this muted response to uncertainty and error is evident neurophysiologically such that religious conviction is associated with reduced activity in the anterior cingulate cortex (ACC), a cortical system involved in a form of attention that serves to regulate both cognitive and emotional processing...

Although it's simplistic of them to say the ERN reflects only ACC activity, they did avoid some of the pitfalls of Amodio et al.'s paper by taking into account personality factors that can influence this brain wave (hence, the "neurotic" and "antisocial" title).

We measured the amplitude of each participant’s ERN during the Stroop task and correlated these values with participants’ self-reported religious zeal (Study 1) and self-reported belief in God (Study 2). In both studies, we also measured other psychological variables to control for their impact on the hypothesized correlation between religious conviction and ACC activity. We expected greater religious conviction to predict lower ERN amplitudes in both studies, even after controlling for important personality traits and cognitive capacities.

And that's what they found.


Fig. 1C (Inzlicht et al., 2009). The relation between religious zeal and anterior cingulate cortex activity: event-related potentials (ERPs) at electrode Cz for error-related negativities (ERNs) for people high and low in religious zeal.

The Religious Zeal scale was used to assess ardent religious conviction. Items included ‘‘I aspire to live and act according to my religious beliefs,’’ ‘‘My religious beliefs are grounded in objective truth,’’ and ‘‘I would support a war that defended my religious beliefs.’’ Behavioral inhibition, behavioral activation, self-esteem, and the need for cognitive closure were also assessed.

However, they repeat some of the drawbacks from Amodio's paper by reporting correlations but only showing a median split (presumably) in the figure (and we don't know if this group difference is significant). We also don't know anything about the reaction times, other than the odd finding that greater religious zealotry was associated with a larger Stroop interference effect (slower for BLUE than for RED) but fewer errors.

In Experiment 2 with a different group of subjects, the self-report measures were belief in God, political conservatism à la Amodio, and the Big Five personality inventory. Here, too, they found that greater religious belief correlated with smaller ERN responses to errors (and personality did not account for this).

Unexplained loose ends? I see at least two of them. First, the estimated localization of the ERN response within the ACC was centimeters apart in the two groups of subjects. Granted, estimated source localization for ERP is tenuous at best (especially with only 32 electrodes), but these two spots are in different functional regions of the ACC.


Fig 1D (top) and Fig 2D (bottom) - illustration of the generator for the ERN (in anterior cingulate cortex), as determined by source localization.

More critically, this experiment failed to replicate Amodio's finding: there was absolutely no correlation between self-assessed conservatism and the ERN wave! [as in this figure] I don't have a high need for cognitive closure, but it appears to be a glaring omission that this was not even mentioned in the paper. I'm feeling a very large error-related negativity at the moment. Maybe I need a Xanax. Or a religious experience...

Footnote

¹ For more on the same study, see Liberals Are Neurotic and Conservatives Are Antisocial, as well as David Amodio Responds to his neurocritics.

References

Amodio DM, Jost JT, Master SL, Yee CM. (2007). Neurocognitive correlates of liberalism and conservatism. Nature Neurosci. 10:1246-1247.

Hajcak G, McDonald N, Simons RF. (2004). Error-related psychophysiology and negative affect. Brain Cogn. 56:189-97.



Michael Inzlicht, Ian McGregor, Jacob B. Hirsh, Kyle Nash (2009). Neural Markers of Religious Conviction Psychological Science DOI: 10.1111/j.1467-9280.2009.02305.x

Studious Nerds Are Neurotic and Party Animals Are Antisocial

From the authors who brought you "Religion is the Xanax of the people" (aka Neural Markers of Religious Conviction) comes the finding that college students with lower grades are similar to religious zealots on a specific neural response to making an error. Meanwhile, students with high GPAs resemble atheists on the same neural marker. However, the new paper by Hirsh and Inzlicht (2009) did not draw a parallel to their previous study (Inzlicht et al., 2009). In fact, the two findings were interpreted in very different terms. In the new article:

A greater ability to monitor performance and engage cognitive-control mechanisms when needed thus appears associated with improved real-world performance.

Meanwhile, in the prior paper:

...religious conviction is marked by reduced reactivity in the anterior cingulate cortex (ACC), a cortical system that is involved in the experience of anxiety and is important for self-regulation. ... These results suggest that religious conviction provides a framework for understanding and acting within one's environment, thereby acting as a buffer against anxiety and minimizing the experience of error.

So the religious people were not utter failures at engaging cognitive control mechanisms, instead they were less anxious. And the smart students were not neurotic, they were better able to monitor their task performance. Hmm.

Before going any further, let's look at the experimental design and the neural measures. Both experiments used EEG recordings, specifically event-related potentials. The ERP brain waves reflect electrophysiological activity recorded remotely from the scalp. While it's great for determining the temporal parameters of neural activity, it's not so great at determining where the activity is located in the brain.

The brain wave of interest is the error-related negativity (ERN), recorded at the time that people make mistakes in a task:

The ERN is evident as a large negative polarity peak in the event-related brain potential waveform that occurs when people make errors in reaction time tasks. It begins at the moment of the error and reaches a maximum about 100 milliseconds later (see Gehring et al., 1993, PDF). It is largest at fronto-central scalp locations and appears to come from an area of the brain called the anterior cingulate cortex...

The task used in both studies was the ever-popular Stroop task, in which color words are presented in font colors that either match or conflict with the printed word. Subjects are told to name the color and ignore the word. The Stroop interference effect (slower for BLUE than for RED) arises because reading is a more automatic process than color naming. Thus, subjects are prone to make errors on this task, and that's what the authors were interested in studying.

The participants were 31 undergraduates who consented to having their transcripts released. Their EEG was measured while they performed the Stroop task, and the ERN was calculated from the response-locked averages on all error trials. The results are illustrated below. Simply put, students with high GPA had a larger ERN response than those with low GPA.


Figure 2 (Hirsh & Inzlicht, 2009). The relation between academic success and the ERN. (A) Event-related potentials at Fz on error trials for individuals with high and low Grade Point Averages, as derived from a tertiary split of the sample. (B) Spatial distribution of the ERN, quantified as the peak minimum voltage deflection occurring between 50 and 150 ms after an error. (C) Headmap of correlations between GPA and ERN magnitude. (D) Source localization indicates an anterior cingulate generator for the ERN.

What might this mean? There is some disagreement about what the ERN wave represents: a direct response to the mismatch between the intended action and the actual one, a more generic response to conflict in general, or an emotional response to f***ing up. The authors opted to impose two different interpretations, so it's not surprising that the ERN can mean different things to different researchers. Or to the same researchers in different contexts. In the present context,

As predicted by models of self-regulation and cognitive control, academic performance was correlated with ERN magnitude, with better grades being associated with stronger (more negative) ERN responses, r= -.40.

"Cognitive control" (a sometimes murky concept) was evaluated by looking at post-error slowing, i.e. how much a person slows down on the trial immediately after making a mistake. If a subject has slowed down a lot, that means he's reined in the overly fast reaction time that led to the error in the first place (by responding more cautiously on the next trial). In the present study, a greater degree of post-error slowing was associated with larger ERN amplitudes and higher grades -- and viewed as an exemplar of greater cognitive control. This was taken to have sweeping implications for the rest of their lives:

Academic performance is a gateway to many important life outcomes, influencing the career options that are available to a student. At the broader societal level, achievement in academic domains plays a vital role in sustaining cultural and scientific innovation. The current study suggests that individuals who are better able to monitor their performance and engage cognitive control mechanisms when needed enjoy greater success in undergraduate programs.

How does this relate to smaller ERNs in highly religious persons? Do religious zealots have poor cognitive control? Or does it mean that lower grades are the Xanax of the people (Inzlicht et al., 2009)?

How is it that religion can bring about both peace of mind and zealous conviction? We suggest that religious conviction buffers against anxiety by providing relief from the experience of uncertainty and error, and in so doing, strengthening convictions and narrowing attention away from inconsistencies. We hypothesize that this muted response to uncertainty and error is evident neurophysiologically such that religious conviction is associated with reduced activity in the anterior cingulate cortex,¹ a cortical system involved in a form of attention that serves to regulate both cognitive and emotional processing.

Read more in Atheists Are Neurotic and Religious Zealots Are Antisocial.



Footnote

¹ However, one cannot say for certain that the anterior cingulate is the sole origin of the ERN, because EEG is recorded from the scalp and not inside the brain.

References

Hirsh, J., & Inzlicht, M. (2009). Error-related negativity predicts academic performance Psychophysiology. DOI: 10.1111/j.1469-8986.2009.00877.x

Inzlicht M, McGregor I, Hirsh JB, Nash K (2009). Neural Markers of Religious Conviction. Psychological Science 20:385-92.

Conservatives Are Neurotic and Liberals Are Antisocial

Since turnabout is fair play, we can no longer say that Liberals Are Neurotic and Conservatives Are Antisocial.

In fact, it's opposite day! But why?


It's because of a new Science article by Oxley et al. (2008). I'm sure you've seen the deluge of articles in the popular press saying that social conservatives¹ are great big scaredy cats when it comes to loud noises and aversive pictures. The headlines are ranked in order of most to least sensationalistic:



Newsweek: Spiders, Maggots, Politics

...in the conservative mind, illegal immigrants may =spiders = gay marriages = maggot-filled wounds = abortion rights = bloodied faces.

Wired Science: Conservatives Scare More Easily Than Liberals, Say Scientists

Deep-seated political differences aren't simply moral and intellectual: They're also biological.

BBC News: Political views 'all in the mind'

...people who are sensitive to fear or threat are likely to support a right wing agenda.

EurekAlert! (Rice University press release): Political attitudes are predicted by physiological traits

Is America's red-blue divide based on voters' physiology? A new paper in the journal Science, titled "Political Attitudes Are Predicted by Physiological Traits," explores the link.

Scientific American: Are you more likely to be politically left or right if you scare easily?

Here's a fun trick: scare someone you don't know, then guess whether they favor the death penalty and the war in Iraq based on how freaked out they got.²

People with stronger startle reactions are more likely to support ideologies associated with conservative American politics, including the Patriot Act, obedience and biblical truth — and less likely to favor gun control, foreign aid, abortion rights, gay marriage and pornography, according to research published in today's Science. Those who are slower to scare are more likely to harbor traditionally liberal politics.

NSF press release: Some Political Views May be Related to Physiology

People who react more strongly to bumps in the night, spiders on a human body or the sight of a shell-shocked victim are more likely to support public policies that emphasize protecting society over preserving individual privacy.

Before I add my $0.02 (which is worth even less now), I'd like to draw your attention to two critiques in the blogosphere. For a good discussion of behavior genetics and heritability issues, read Gene Expression on Conservatives Have More Fear:

By heritability, I mean that you can predict an X proportion of the variation on trait Y from the variation of genes. Does this mean that there was selection for conservatism and liberalism in the past? Does this mean that there are genes for conservatism and liberalism? NO!!! That's just plain retarded.

For another excellent critique, I highly recommend A spider on your face won't stop me from criticizing this article by John Hawks. He provides a list of 7 erroneous assumptions and methodological flaws:

1. Sampling: By going from a sample of over 1310 down to 46 individuals, the authors were in a position to cull the sample in many ways that might influence their outcome. ...

That was my number one question as well. There is nothing in the main paper or the supporting online material (PDF) about whether the authors excluded (or included) subjects with things like anxiety disorders, for instance. How they settled on the final n=46 is murky.

2. Presentation of results: The methods employed are multiple regressions, using the dependent as a continuous variable. Yet the graphs in the paper show the dependent as a dichotomous variable. The graphs are designed to show the result to be as visually large as possible, but in so doing, they don't report the actual results, which are visually much weaker (while still statistically significant).

I won't go through the list point by point, but other objectionable aspects include lumping together the moderates and the conservatives, having a "made-up category" as the dependent variable ("has the look of a fishing expedition"), and not controlling for religious attitudes (!!).

The only thing I can add to the conversation is a brief discussion of the published literature on startle and personality. But first let's return to the beginning with the inversion of this post's title. In a famous study from last year, David Amodio and colleagues showed that an EEG wave related to making mistakes in a speeded reaction time task (called the error-related negativity or ERN) was larger in liberals than it was in conservatives. The authors also wanted to relate the ERN wave to conflict monitoring to conclude that liberals were more flexible in their thinking:

...greater liberalism was associated with stronger conflict-related anterior cingulate activity, suggesting greater neurocognitive sensitivity to cues for altering a habitual response pattern.

OK, then. After questioning whether the ERN was even related to conflict monitoring, I reviewed the literature on ERN and psychopathology.³ Briefly, liberals and individuals with clinical diagnoses such as obsessive-compulsive disorder or major depressive disorder have larger ERN waves, while conservatives and individuals with schizophrenia or psychopathy show smaller ERN waves than control participants.

These findings extend to the normal population, i.e., people who do not fit the criteria for a clinical diagnosis, but who score higher or lower on certain traits. For example, people who score high on negative affect have bigger ERNs, while individuals with "externalizing psychopathology" have smaller ERNs. Does this mean that liberals are neurotic and conservatives are antisocial?

Well, no, if you look at startle response, it's the reverse. Although the difference was not statistically significant,⁴ conservatives high supporters of socially protective policies had a larger eyeblink startle response to random loud bursts of white noise than liberals.


Fig. 3 (Oxley et al., 2008). Mean blink amplitude in response to all seven startling noises for high supporters and low supporters of socially protective politics. Bars are mean blink amplitudes (in millivolts). Difference of means tests for overall means: t = 1.64, P = 0.10.

But is the startle reflex comparable to the ERN brain wave? Hajcak and Foti (2008) say they're related:

We found that (a) the defensive startle response was larger following errors than following correct responses, and (b) the magnitude of the ERN predicted the degree of startle potentiation following errors.

And what about the skin conductance response to aversive vs. neutral pictures? The SCR was recorded in another experiment that showed the participants pictures of bunnies and bloody faces. The conservatives' SCRs to aversive images were larger than those in the liberals, but the two groups were comparable for the nonthreatening images. How is the SCR related to the ERN? Hajcak (et al., 2004) again:

An enhanced ERN has consistently been observed in anxious subjects and there is some suggestion that the ERN is related to general negative affective experience (NA). The ERN has been source localized to the anterior cingulate cortex-a structure implicated in the regulation of affective, response selection, and autonomic resources. Thus, the findings that autonomic measures and affective distress are related to response monitoring are consistent with anterior cingulate cortex function. ... Results indicate that high NA was associated with significantly greater ERN and error-related SCR...

The only way to reconcile the findings from Oxley et al. (2008) and Amodio et al. (2007) is to postulate that the conservatives in the latter study were unaware of making errors in a very very simple task. Oh, OK, the other explanation is that the group classification schemes used by the two labs are not related.⁵

I do have a final question on the choice of physiological measures. It appears to be commonplace in the literature for studies to examine how prior presentation of aversive pictures affects the startle response. For example, unlike controls, psychopaths (Justus & Finn, 2007) do not show an enhanced startle to aversive pictures (compared to neutral pictures), while those with borderline personality disorder (Hazlett et al., 2007) show an exaggerated response.

Yet, Oxley et al. looked at these two measures separately. Why? Being more fearful (of certain things) does indeed come with being a xenophobic supporter of socially protective policies, but I would have liked to have learned how the startle response was affected by various pictures, not only of spiders and maggots, but also of undocumented immigrants and gay wedding scenes. But, I think we already know the answer to that question...



Footnotes

¹ Oxley et al. (2008) expressly stated that they did not want to use the labels "liberal" or "conservative" -- preferring to describe the more easily startled group as those who

advocate policies that protect the existing social structure from both external (outgroup) and internal (norm-violator) threats.

² The SciAm article does ask the question:

But what comes first: biology or politics? "It could be working either way," says study author John Alford...

³ See that post for a full list of references, which were removed here for brevity.

⁴ Or more precisely:

Although the difference was not significant in the bivariate analysis, when the sociodemographic controls were added to better specify the model, the coefficient for blink amplitude was again in the predicted (positive) direction, sizable (standardized regression coefficient = 0.286), and statistically significant (P = 0.03).

⁵ Amodio et al. simply asked subjects to rate their political attitudes on a -5 (extremely liberal) to +5 (extremely conservative) scale.

References

Amodio DM, Jost JT, Master SL, Yee CM. (2007). Neurocognitive correlates of liberalism and conservatism. Nature Neurosci. 10:1246-7.

Hajcak G, Foti D. (2008). Errors are aversive: defensive motivation and the error-related negativity. Psychol Sci. 19:103-8.

Hajcak G, McDonald N, Simons RF. (2004). Error-related psychophysiology and negative affect. Brain Cogn. 56:189-97.

Hazlett EA, Speiser LJ, Goodman M, Roy M, Carrizal M, Wynn JK, Williams WC, Romero M, Minzenberg MJ, Siever LJ, New AS. (2007). Exaggerated affect-modulated startle during unpleasant stimuli in borderline personality disorder. Biol Psychiatry 62:250-5.

Justus AN, Finn PR. (2007). Startle modulation in non-incarcerated men and women with psychopathic traits. Pers Individ Dif. 43:2057-2071.

D. R. Oxley, K. B. Smith, J. R. Alford, M. V. Hibbing, J. L. Miller, M. Scalora, P. K. Hatemi, J. R. Hibbing (2008). Political Attitudes Vary with Physiological Traits. Science, 321 (5896), 1667-1670 DOI: 10.1126/science.1157627

The Error of Prognosticating Political View by Brain Wave

Figure 1. Liberals and conservatives in the study of Amodio et al. (2007) voted primarily for Kerry and Bush, respectively, in 2004. Brain wave recordings adapted from Mathalon et al. (2002).

You've seen the headlines:

Brains of liberals, conservatives may work differently, study finds

. . .

In a study likely to raise the hackles of some conservatives, psychologist David Amodio and others found that a specific region of the brain’s cortex is more sensitive in people who consider themselves liberals than in self-declared conservatives.

The brain region in question helps people shift gears when their usual response would be inappropriate, supporting the notion that liberals are more flexible in their thinking.

And the overblown quotes:

Are We Predisposed to Political Beliefs?

...

"In the past, people thought that…[political leanings were]…all environmentally influenced, a combination of biological dispositions as well as cultural shaping," says David Amodio, an assistant professor of psychology at New York University. However, a new study, led by Amodio, indicates that political bent "is not just a choice people have, but it seems to be linked to fundamental differences in the way people process information."

And the baseless assertion of innate differences between the brains of liberals and conservatives:

brain neurons of liberals and conservatives fire differently [sic] when confronted with tough choices, suggesting that some political divides may be hard-wired, according a study released Sunday.

But perhaps you've read a critical analysis of the leaps of logic made in the study (and if you haven't read it, you should):

Liberal and Conservative Anterior Cingulate Cortices

. . .

Let's face it, the intro to this paper, which is necessarily short because it's only a "brief communication," is terrible. I have no idea why they hypothesized a relationship between, say, tolerance for uncertainty and conflict monitoring. That hypothesis feels about as non sequitur as this:

Given that these associations between political orientation and cognitive styles have been shown to be heritable, evident in early childhood, and relatively stable across the lifespan, we hypothesized that political orientation may be associated with individual differences in a basic neurocognitive mechanism involved broadly in self-regulation. (p. 1)

Well alrighty, then. Eye color is heritable, evident in early childhood, and relatively stable across the lifespan, but I've never seen someone associate it with self-regulation.

The Neurocritic has another ax to grind, a problem with attributing the observed results to political viewpoint and not to other factors. First, let's start out with the measures of brain activity reported in the paper. The study used EEG recordings, specifically event-related potentials. The ERP brain waves reflect electrophysiological activity recorded remotely from the scalp. While it's great for determining the temporal parameters of neural activity, it's not so great at determining where the activity is located in the brain.

One brain wave of interest here is

the No-Go N2 component, which is believed to reflect conflict-monitoring activity associated with the successful inhibition of the prepotent Go response on No-Go trials.

Another brain wave of interest is the error-related negativity (ERN), recorded at the time that people make mistakes in a task:

The response-locked error-related negativity (ERN), which peaks at approximately 50 ms following an incorrect behavioral response, reflects conflict between a habitual tendency (for example, the Go response) and an alternative response (for example, to inhibit behavior in response to a No-Go stimulus).

However, it's not at all clear that ERN reflects conflict-monitoring (Carbonnell & Falkenstein, 2006). Thus, based on a smaller-sized ERN in conservatives, one cannot conclude that they are "less responsive to conflict." In fact, if one wants to apply the logic of conflict monitoring to political viewpoint, one could say that conservatives might be more freaked out by ambiguity and conflict, since it violates their simplistic world view.

Anyway, back to the experiment. The participants in the study performed a Go/No-Go task that involved rapid responses to the letter "M" on 80% of the trials, and withholding a response to the letter "W" on 20% of the trials. The ERN was recorded when people incorrectly responded to W, and N2 was recorded when people correctly refrained from responding to W.

What were the results? Liberals showed larger ERN waves than conservatives when mistakenly responding on No-Go trials. However, so do individuals with clinical diagnoses such as obsessive-compulsive disorder (Gehring et al., 2000) or major depressive disorder (Chiu & Deldin, 2007).

Figure 2. ERN waves for liberals versus conservatives (left; adapted from Fig. 1b of Amodio et al.) and for OCD versus control participants (right; adapted from Fig. 1 of Gehring et al.).

On the other hand, individuals with schizophrenia (Mathalon et al., 2002) or psychopathy (Munro et al., 2007) show smaller ERN waves than control participants. These findings extend to the normal population, i.e., people who do not fit the criteria for a clinical diagnosis, but who score higher or lower on certain traits. For example, people who score high on negative affect have bigger ERNs (Hajcak et al., 2004), while individuals with "externalizing psychopathology"¹ have smaller ERNs (Hall et al., 2007). Does this mean that liberals are neurotic and conservatives are antisocial? Since these were not assessed along with political orientation, we can only hazard a guess...


Footnote

¹ According to Hall et al. (2007):

Recent research examining patterns of diagnostic co-morbidity in community-epidemiological samples indicates that conduct disorder in children, antisocial behavior in adults, and substance-use disorders—along with personality traits related to behavioral disinhibition—are indicators of a common underlying vulnerability factor, labeled externalizing.

References

Amodio DM, Jost JT, Master SL, Yee CM. (2007). Neurocognitive correlates of liberalism and conservatism. Nature Neurosci. Published online 9 September 2007.

Political scientists and psychologists have noted that, on average, conservatives show more structured and persistent cognitive styles, whereas liberals are more responsive to informational complexity, ambiguity and novelty. We tested the hypothesis that these profiles relate to differences in general neurocognitive functioning using event-related potentials, and 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.

Carbonnell L, Falkenstein M. (2006). Does the error negativity reflect the degree of response conflict? Brain Res. 1095:124-30.

Chiu PH, Deldin PJ. (2007). Neural evidence for enhanced error detection in major depressive disorder. Am J Psychiatry 164:608-16.

Gehring WJ, Himle J, Nisenson LG. (2000). Action-monitoring dysfunction in obsessive-compulsive disorder. Psychol Sci. 11:1-6.

Hajcak G, McDonald N, Simons RF. (2004). Error-related psychophysiology and negative affect. Brain Cogn. 56:189-97.

Hall JR, Bernat EM, Patrick CJ. (2007). Externalizing psychopathology and the error-related negativity. Psychol Sci. 18:326-33.

Mathalon DH, Fedor M, Faustman WO, Gray M, Askari N, Ford JM. (2002). Response-monitoring dysfunction in schizophrenia: an event-related brain potential study. J Abnorm Psychol. 111:22-41.

Munro GE, Dywan J, Harris GT, McKee S, Unsal A, Segalowitz SJ. (2007). ERN varies with degree of psychopathy in an emotion discrimination task. Biol Psychol. 76:31-42.

ADDENDUM: Cognitive Daily has just posted another critique of this paper, The claim: Politically liberal brains are better at handling change

Liberals Are Conflicted and Conservatives Are Afraid

This sums up the basic conclusion of a new study on political orientation and brain structure by Ryota Kanai, Tom Feilden, Colin Firth and Geraint Rees in the journal Current Biology. Yes, that Colin Firth...

Colin Firth's Speech during the 2011 Academy Awards. Firth won Best Actor for The King's Speech.


Why are Colin Firth and Tom Feilden, both listed with BBC Radio 4 affiliations, authors on this paper? Let's go back to Tuesday, 28 December 2010 and two pieces that appeared on the BBC website.

Politics: Brain or background?

Science correspondent Tom Feilden: "What started out as a bit of fun has turned into quite a significant piece of science."

Scientific research commissioned by this programme on behalf of our guest editor, Colin Firth, has shown a strong correlation between the structure of a person's brain and their political views.

You can also listen to a brief audio clip of Feilden discussing the study at the link above. Firth actually commissioned Professor Geraint Rees at University College London to obtain structural MRI scans from two diametrically opposed politicians: conservative MP Alan Duncan (a member of the Conservative Party) and liberal MP Stephen Pound (a member of the Labour Party).

Feilden then asks a question that is unanswerable from studying brain structure in adults: "Are political beliefs learnt, the product of experiences in our environment, or 'hard wired' in the brain?" Since a comparison of n=1 liberal versus n=1 conservative is not scientifically valid, Rees went back to a database of MRI scans from UCL students and asked these participants about their political beliefs. Feilden then discussed the results before the paper had been formally submitted for publication [according to the journal website, the paper was received by Current Biology on 11 January, 2011]. Briefly, he said that the gray matter of the anterior cingulate cortex was thicker among the liberal or left wing participants while the amygdala was much larger in those who identified as conservative or right wing.

"But is it cause and effect?" asks an interviewer. Rightfully so. Correlation does not equal causation. Then there's the claim that the structural brain variation means the political differences are "hard wired". The observed anatomical differences prove no such thing. Any experience will change the brain in some way, and repeated patterns of behavior, whether it's learning to juggle or voting conservative due to a certain set of core beliefs, can alter the brain. Nonetheless, we have the following headline:

Are political beliefs hard-wired?

Tom Feilden| 08:10 UK time, Tuesday, 28 December 2010

"Give me the child until he's seven and I'll give you the man."
It's clear from their motto that the Jesuits are firmly in the acquired camp when it comes to whether our political beliefs and values are learned or hard wired from birth: the product of experience rather than genetics.
But is that true?

...along with the eventual admission:

Although the results do show that political belief is reflected in the physical structure of the brain it's not clear which comes first. Whether the structure of the brain shapes political belief or political belief leads to the differential development of brain structure.

All right, that was a media stunt, you say -- but how about the peer reviewed paper (Kanai et al., 2011)?

A total of 90 healthy middle-class to upper-class participants (mean age = 23.5 yrs) underwent MRI scanning and [later?] filled out a very brief questionnaire on their political views:

Participants were asked to indicate their political orientation on a five-point scale of very liberal (1), liberal (2), middle-of-the-road (3), conservative (4), and very conservative (5). ... Because none of the participants reported the scale corresponding to very conservative, the analyses were conducted using the scales of 1, 2, 3, and 4.

If I'm not mistaken, no special effort was made to recruit very conservative participants, because the study was conceived after the MRIs were obtained.

As reported by Feilden, being liberal was associated with a larger anterior cingulate whereas being conservative was associated with a larger right amygdala¹ (see Figure 1 below).


Figure 1 (Kanai et al., 2011). Individual Differences in Political Attitudes and Brain Structure. (A) Regions of the anterior cingulate where gray matter volume showed a correlation with political attitudes are shown overlaid on a T1-weighted MRI... A statistical threshold of p < 0.05, corrected for multiple comparisons, is used for display purposes. The correlation (left) between political attitudes and gray matter volume (right) averaged across the region of interest (error bars represent 1 standard error of the mean, and the displayed correlation and p values refer to the statistical parametric map presented on the right) is shown. (B) The right amygdala also showed a significant negative correlation between political attitudes and gray matter volume. Display conventions and warnings about overinterpreting the correlational plot (left) are identical to those for (A).

The results were based on measurements of gray matter density in these two specific structures. How were they chosen? First, the anterior cingulate was selected based on the finding of Amodio et al. (2007) that...

...the amplitude of event-related potentials reflecting neural activity associated with conflict monitoring in the anterior cingulate cortex (ACC) is greater for liberals compared to conservatives. Thus, stronger liberalism is associated with increased sensitivity to cues for altering a habitual response pattern and with brain activity in anterior cingulate cortex.

I had issues with this interpretation of the Amodio et al. study in 2007, which I will summarize here. One problem was attributing the observed results to political viewpoint and not to other factors. The study used EEG recordings, specifically event-related potentials. The ERP brain waves reflect electrophysiological activity recorded remotely from the scalp. While it's great for determining the temporal parameters of neural activity, it's not so great at determining where the activity is located in the brain.

One brain wave of interest was the error-related negativity (ERN), recorded at the time that people make mistakes in a task:

The response-locked error-related negativity (ERN), which peaks at approximately 50 ms following an incorrect behavioral response, reflects conflict between a habitual tendency (for example, the Go response) and an alternative response (for example, to inhibit behavior in response to a No-Go stimulus).

However, it's not at all clear that ERN reflects conflict-monitoring (Carbonnell & Falkenstein, 2006). Thus, based on a smaller-sized ERN in conservatives, one cannot conclude that they are "less responsive to conflict." In fact, if one wants to apply the logic of conflict monitoring to political viewpoint, one could say that conservatives might be more freaked out by ambiguity and conflict, since it violates their simplistic world view. Although liberals did indeed show larger ERN waves than conservatives when making mistakes, so do individuals with clinical diagnoses such as obsessive-compulsive disorder (Gehring et al., 2000) or major depressive disorder (Chiu & Deldin, 2007). So we can't dismiss the possibility that the liberals might have been more depressed or obsessive compulsive than the conservatives.

Back to the present day, the specific ACC region of interest (ROI) was chosen from an fMRI study [not the EEG study, which has lower spatial resolution] entitled, "A midline dissociation between error-processing and response-conflict monitoring" (Garavan et al., 2003). Garavan and colleagues found that different locations in the medial frontal cortex responded preferentially to error processing (the ACC ROI selected by Kanai et al., 2011) and to conflict monitoring (a more posterior and dorsal region called the pre-SMA). However, Kanai and colleagues concluded:

Thus, it is conceivable that individuals with a larger ACC have a higher capacity to tolerate uncertainty and conflicts, allowing them to accept more liberal views. Such speculations provide a basis for theorizing about the psychological constructs (and their neural substrates) underlying political attitudes. However, it should be noted that every brain region, including those identified here, invariably participates in multiple psychological processes. It is therefore not possible to unambiguously infer from involvement of a particular brain area that a particular psychological process must be involved.

But it seems to me that if you want to say "a higher capacity for conflict correlates with a larger X brain region", based on Garavan et al. you'd have to choose the pre-SMA and not the ACC.

Although Kanai et al. did offer caveats, other issues with their paper were raised by Professor Martha Farah in a ScienceNOW article, Does Your Brain Bleed Red, White, and Blue?

It's an appealing story and a topic worth investigating, says cognitive neuroscientist Martha Farah of the University of Pennsylvania. But there's plenty of reason to be cautious, she says. For one, it's not clear what a bigger amygdala—or a bigger anything in the brain—actually means in terms of brain function and behavior. The research, she says, is unclear and often contradictory on this point.

Another problem is that most brain regions have multiple functions, Farah says: "Who says fear is the only function of the amygdala?" She notes that this brain region also responds to sexually arousing images and pictures of happy faces, and one recent study found a correlation between amygdala volume and the size of people's social networks. Likewise, the anterior cingulate cortex has been implicated in a long list of cognitive functions. By picking and choosing from the previous studies, "they're indulging in a bit of just-so storytelling," Farah says.

After all this criticism, I have to point out an impressive aspect of the paper, and that is the replication of results in an independent group of 28 participants. In the end, I don't doubt that there are differences between the brains of liberal and conservative people. But how they got that way, and what it means, are questions for further investigation.

Footnote

¹ Why only the right amygdala and not the left? The authors didn't provide an explanation.

Further Reading

Additional posts on the "political brain" by The Neurocritic:

The Error of Prognosticating Political View by Brain Wave

Liberals Are Neurotic and Conservatives Are Antisocial

David Amodio Responds

Conservatives Are Neurotic and Liberals Are Antisocial

References

Amodio DM, Jost JT, Master SL, Yee CM. (2007). Neurocognitive correlates of liberalism and conservatism. Nature Neurosci. 10:1246-7.

Carbonnell L, Falkenstein M. (2006). Does the error negativity reflect the degree of response conflict? Brain Res. 1095:124-30.

Chiu PH, Deldin PJ. (2007). Neural evidence for enhanced error detection in major depressive disorder. Am J Psychiatry 164:608-16.

Gehring WJ, Himle J, Nisenson LG. (2000). Action-monitoring dysfunction in obsessive-compulsive disorder. Psychol Sci. 11:1-6.

Garavan H, Ross TJ, Kaufman J, Stein EA. (2003). A midline dissociation between error-processing and response-conflict monitoring. Neuroimage 20:1132-9.

Ryota Kanai, Tom Feilden, Colin Firth, Geraint Rees (2011). Political Orientations Are Correlated with Brain Structure in Young Adults Current Biology : PMID: 21474316

Liberals Are Conflicted and Conservatives Are Afraid?

Senate Majority Leader Harry Reid (D-Nev.), left, and House Speaker John Boehner.
Harry Reid, John Boehner can't agree on why Congress can't agree to avert government shutdown