Here is the original research article from Nature Neuroscience:Exploring the neurobiology of politics, scientists have found that liberals tolerate ambiguity and conflict better than conservatives because of how their brains work.
Scientists at New York University and the University of California, Los Angeles, showed through a simple experiment to be reported today in the journal Nature Neuroscience that political orientation is related to differences in how the brain processes information.
Previous psychological studies have found that conservatives tend to be more structured and persistent in their judgments, whereas liberals are more open to new experiences. The latest study found those traits are not confined to political situations but also influence everyday decisions.
The results showed "there are two cognitive styles - a liberal style and a conservative style," said UCLA neurologist Dr. Marco Iacoboni, who was not connected to the latest research.
Participants were college students whose politics ranged from "very liberal" to "very conservative." Scientists instructed them to tap a keyboard when an M appeared on a computer monitor and to refrain from tapping when they saw a W.
M appeared four times more frequently than W, conditioning participants to press a key in knee-jerk fashion whenever they saw a letter.
Each participant was wired to an electroencephalograph that recorded activity in their anterior cingulate cortex, the part of the brain that detects conflicts between a habitual tendency (pressinga key) and a more appropriate response (not pressing the key). Liberals had more brain activity and made fewer mistakes than conservatives when they saw a W, researchers said. Liberals and conservatives were equally accurate in recognizing M.
Researchers obtained the same results when they repeated the experiment in reverse, asking another set of participants to tap when they saw W.
Frank Sulloway, a researcher at the Institute of Personality and Social Research, at the University of California, Berkeley, who was not involved in the study, said results "provided an elegant demonstration that individual differences on a conservative-liberal dimension are strongly related to brain activity."
Analyzing the data, Sulloway said liberals were 4.9 times more likely than conservatives to show activity in the brain circuits that deal with conflicts and were 2.2 times more likely to score in the top half of the distribution for accuracy.
Based on the results, Sulloway said, liberals could be expected to more readily accept new social, scientific or religious ideas.
Lead author David Amodio, an assistant professor of psychology at NYU, cautioned that the study looked at a narrow range of human behavior and it would be a mistake to conclude that one political orientation was better than another. The tendency of conservatives to block distracting information could be a good thing depending on the situation, he said.
http://www.nature.com/neuro/journal/vao ... n1979.html
Political scientists and psychologists have long noted differences in the cognitive and motivational profiles of liberals and conservatives in the USA and elsewhere. Across dozens of behavioral studies, conservatives have been found to be more structured and persistent in their judgments and approaches to decision-making, as indicated by higher average scores on psychological measures of personal needs for order, structure and closure1. Liberals, by contrast, report higher tolerance of ambiguity and complexity, and greater openness to new experiences on psychological measures. 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 lifespan2, 3, we hypothesized that political orientation may be associated with individual differences in a basic neurocognitive mechanism involved broadly in self-regulation.
Behavioral research suggests that psychological differences between conservatives and liberals map onto the widely-studied self-regulatory process of conflict monitoring4. Conflict monitoring is a general mechanism for detecting when one's habitual response tendency is mismatched with responses required by the current situation, and this function has been associated with neurocognitive activity in the anterior cingulate cortex (ACC)5. For example, in the Go/No-Go task used in our study, participants must quickly respond to a frequently presented Go stimulus, such that the 'Go' response becomes habitual. However, on a small proportion of trials, a No-Go stimulus appears, signaling that one's habitual response should be withheld. Hence, a No-Go stimulus conflicts with the prepotent Go response tendency. Such response conflict is typically associated with enhanced ACC activity, measured using functional magnetic resonance imaging or event-related potentials (ERPs)6, 7. We proposed that differences in conservatives' and liberals' responsiveness to complex and potentially conflicting information relates to the sensitivity of this general mechanism for monitoring response conflict.
To test the hypothesis that political liberalism (versus conservatism) would be associated with greater conflict-related ACC activity, we recorded electroencephalographs from 43 right-handed subjects (63% female) as they performed the Go/No-Go task. Subjects reported their political attitudes confidentially on a -5 (extremely liberal) to +5 (extremely conservative) scale. This single-item measure has been found to account for approximately 85% of the statistical variance in presidential voting intentions in American National Election studies between 1972 and 2004 (ref.. Among participants in the present study who reported voting in the 2004 presidential election, a more liberal (versus conservative) ideological orientation strongly predicted voting for John Kerry versus George Bush (r(21) = 0.79, P < 0.001).
In our study, conflict-related ACC activity was indexed by two ERP components. ERPs are scalp-recorded voltage changes reflecting the concerted firing of neurons in response to a psychological event. The response-locked error-related negativity (ERN), which peaks at approximately 50 ms following an incorrect behavioral response9, 10, 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)11. We also examined 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 trials7. Relationships between political orientation and these neurocognitive indices were examined using correlation analyses (two-tailed).
Political orientation was strongly correlated with ERN amplitudes (r(41) = 0.59, P < 0.001; Fig. 1a), as well as with No-Go N2 amplitudes (r(41) = 0.41, P < 0.01). Specifically, liberalism (versus conservatism) was associated with significantly greater conflict-related neural activity when response inhibition was required (that is, on No-Go trials; Fig. 1b). ERPs associated with correct Go responses, scored to correspond to the ERN and No-Go N2, were not related to political orientation (P's > 0.37). Supplementary source localization analyses confirmed that the ERN and the N2 originated from activity in the dorsal ACC (accounting for 90% and 91% of signal variance, respectively; Fig. 1c, see also Supplementary Fig. 1 and Supplementary Methods online), which is consistent with previous results7, 10.
Figure 1. The relation between political orientation and a neurocognitive index of conflict monitoring.
(a) Political liberalism was associated with larger No-Go error-related negativity (ERN) amplitudes, as indicated by more negative scores, suggesting greater neurocognitive sensitivity to response conflict. (b) ERP waveforms corresponding to No-Go errors, with the waveform for correct Go responses subtracted, are shown for both liberal and conservative participants (response made at 0 ms; ERN peaked at 44 ms postresponse), with the inset showing the voltage map of the scalp distribution of the ERN. (c) Source localization indicates a dorsal anterior cingulate generator for the ERN, computed at peak amplitude (red line in panel b).
Full Figure and legend (45K)
Larger average ERN amplitudes corresponded to better behavioral accuracy on No-Go trials (r(41) = 0.49, P < 0.001), but were unrelated to accuracy on Go trials. No-Go N2 amplitudes were not related to behavior. In addition, stronger liberalism was correlated with greater accuracy on No-Go trials (r(41) = 0.30, P < 0.05). This association suggests that a more conservative orientation is related to greater persistence in a habitual response pattern, despite signals that this response pattern should change (for example, on No-Go trials). This behavioral finding is consistent with the relationship that we observed between political orientation and neurocognitive sensitivity to response conflict. However, a partial correlation analysis revealed that the relation between political attitudes and the ERN remained strong after covarying behavioral accuracy (r(40) = 0.53, P < 0.001), suggesting that liberalism (versus conservatism) is associated with greater neurocognitive sensitivity to cognitive conflict, beyond what was observed from behavioral performance alone.
Taken together, our results are consistent with the view that political orientation, in part, reflects individual differences in the functioning of a general mechanism related to cognitive control and self-regulation1, 2, 3. Stronger conservatism (versus liberalism) was associated with less neurocognitive sensitivity to response conflicts. At the behavioral level, conservatives were also more likely to make errors of commission. Although a liberal orientation was associated with better performance on the response-inhibition task examined here, conservatives would presumably perform better on tasks in which a more fixed response style is optimal.
The study of personality variables that accompany differences in political opinions goes back more than fifty years12. Although recent work has demonstrated neural correlates of political information processing and candidate preferences13, 14, this is the first study connecting individual differences in political ideology to a basic neurocognitive mechanism for self-regulation. These findings may serve to promote the integration of theorizing in the traditionally disparate fields of political psychology and cognitive neuroscience. More broadly, this research demonstrates how integration across multiple levels of analysis can begin to elucidate how abstract, seemingly ineffable constructs, such as ideology, are reflected in the human brain.
Somewhat gimmicky. Characteristically American.