It may be time to take the phrase "political viewpoint" literally. A new study suggests that liberals are more likely than conservatives to follow other people's eye movements.

People normally respond to "gaze cues," or the direction that another person is looking, by glancing to see what caught that person's attention. The new study, to be published in a forthcoming issue of the journal Attention, Perception & Psychophysics, finds that liberals respond much more strongly to such cues than conservatives. The finding is the latest in a series of clues that liberals and conservatives may be subtly different on a biological level, said study researcher Michael Dodd, a psychologist at the University of Nebraska, Lincoln. 

"Across a variety of tasks, we are beginning to find a consistent pattern where conservatives are more responsive to threat/disgust, more responsive to angry faces, and less sensitive to gaze cues than liberals," Dodd wrote in an e-mail to LiveScience. "Liberals, on the other hand, are proving to be more responsive to positive/appetitive stimuli, more responsive to happy faces, and more sensitive to gazes."

Eyes on the prize

In the current study, 72 undergraduate students sat at a computer screen displaying a drawing of a face. The volunteers were instructed to keep their eyes on the face, but were told that the face was irrelevant.

Initially, the face had no pupils, but shortly after the experiment began, pupils appeared and started moving left or right. Just after that, a target image showed up on either the left or right side of the screen, unrelated to the angle of the pupils. The volunteers' job was to press the spacebar key the instant they saw the target image appear.

Despite being told to ignore the face, the participants were generally 10 to 15 milliseconds faster at responding to the target if the pupils appeared to be looking at the spot where the target image would appear. That's a standard result and not so surprising, Dodd said. But when the researchers divided the students by their political beliefs, they found that liberals responded 20 milliseconds more quickly to gaze cues than did conservatives, who didn't show any indication that the face's gaze affected them.

Autonomy and influence

There are several possible explanations for the result, Dodd said. One possibility is that liberals are more empathetic and thus more responsive to others. Another theory is that conservatives are better at following instructions and were thus more likely to listen when the researchers said to ignore the face.

Dodd and his colleagues believe that a more likely explanation is that conservatives value personal autonomy more than liberals, making them less likely to be influenced by others.

The results are correlational, meaning there's no way to know whether your tendency to pay attention to others influences your political beliefs or whether political beliefs change behavior.

"Both possibilities exist," Dodd said. "I do tend to think that it is more likely that basic cognitive biases influence how you process the world, making you more or less likely to seek out liberal or conservative ideals."

The researchers are now analyzing data from a similar study done on a more diverse sample of volunteers. Nebraska leans conservative, Dodd said, so it remains to be seen whether the results will hold for areas that skew liberal.

"I think the important thing to take from this line of research is that it is another piece of evidence that biology can influence political temperament," Dodd said. "I don't think it is the sole influence, but it is another important piece of the puzzle that should not be ignored."

This article was reprinted with permission from LiveScience.

Related on LiveScience: