Political Leanings May Show in Brain
Scientists See Differences in Brain Scans of Liberals and Conservatives During Conflict Test
Sept. 10, 2007 -- Liberals and conservatives may handle mental conflict
differently, according to new research on the brain.
The finding comes from researchers including David Amodio, PhD, a research
scientist in New York University's psychology department. They scanned the
brains of 43 adults during a conflict test.
As part of a confidential personality survey, participants rated their
political orientation on a scale ranging from -5 (for extremely liberal) to +5
(for extremely conservative).
After finishing the survey, they donned stretchy caps studded with
electrodes to scan their brains during the conflict test.
The test had nothing to do with candidates, votes, or prickly political
Participants watched a computer screen that displayed the letter "M"
or "W" for a split second in rapid succession.
The researchers asked half of the group to press a computer key whenever
they saw "M" but not "W." The other half of the group got the
opposite assignment -- press the button for "W" but not
Most of the time, participants saw the letter that was supposed to prompt
them to press the computer key. But 20% of the time, they saw the other letter
and were supposed to refrain from pushing the computer key.
Compared with conservatives, liberals were more likely to refrain from
pressing the computer key when the wrong letter appeared. Liberals also showed
more activity in a brain area called the anterior cingulate cortex, which is
involved in monitoring conflicting information, note Amodio and colleagues.
"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,"
write the researchers.
The study appears in the advance online edition of the journal Nature
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