Why Negative Campaigns Sometimes Win

Feb. 6, 2008 — -- When a politician apologizes for a nasty rumor he or she spread about an opponent, and asks people not to believe it, you can bet on one thing: More people will believe it's true. That's one of the reasons why negative campaigns so often work.

Cognitive scientists have even found evidence that people are predisposed to believe a statement is true, even if it obviously isn't. Humans' urge to affirm, rather than deny, is manifested even in body motions, according to the new study out of the University of Memphis and Cornell University.

"What our research suggests is your whole body seems to show this tendency," to want to believe, psychologist Rick Dale of the University of Memphis, said in an interview. Dale is co-author of a paper describing the research in the January issue of Psychological Science.

Dale and Michael J. Spivey of Cornell completed a project that was created by a computer scientist, Chris McKinstry, who took his own life while the research was underway.

The researchers found that participants in their study really wanted to confirm a question, especially if it was ambiguous.

"Specifically, we found that evaluating a proposition as false, exhibits more difficulty, compared with evaluating a proposition as true," they said in their report.

But that was a bonus prize. What the researchers set out to show was that, contrary to widespread beliefs, the brain shares its biases with the body, even before the cognitive processes are completed. That was revealed in the arm motions of 141 college-age participants, who were asked to decide if 11 questions were true or false.

The participants — 97 females and 44 males — were seated at a computer, and asked to move the cursor from the bottom center of the screen to one of two boxes at the top left and top right corner of the screen, if they believed a statement was true or false.

The statements, read randomly into headphones, had different levels of probability, ranging from "Should you brush your teeth everyday," an obvious yes, to "Is murder sometimes justifiable," maybe yes and maybe no, to "Is a thousand more than a billion," an obvious no.