"the more liberal-minded volunteers were better able to avoid the knee-jerk reaction."
This one of the conclusions from a study by David Amodio of New York University (summarized here at Scientific American Mind).
In the test, liberals and conservatives were asked to hit a button every time they saw M but not W. Given that M appeared about 80% of the time, hitting the button became a reflex. Liberals were more able to suppress this reflex when faced with the wrong stimulus. (Past studies have indicated that liberals are more comfortable with ambiguity and conservatives need structure. I look around my office and suspect that I need to hire a conservative office assistant.)
There are certainly exceptions to this general tendency. George Will stands out as someone who seems to generally think before making pronouncements. Huckabee, Ron Paul, and John McCain seem comfortable defying some of the typical conservative stereotypes. But after watching Republicans shout "tax cut" in response to every situation they face - including massive deficits and the expenses of war - this indictment sounds pretty spot on to me: conservatives are more likely to give the right response in the wrong situation.
In fact, coming from a family of conservatives, I can say that they often don't even need a stimulus to provide their canned responses. Like a back seat driver continually shouting "Turn right!" whether or not there is even an intersection, conservatives will eventually wonder why it is the country has tuned them out.
[Thanks to my daughter Jordan, the cog sci major, for this odd and interesting tip.]