With the presidential elections just two short months away, new research discovered people tend to ignore political information that challenges their beliefs.

During the 2008 presidential campaign, researchers instructed participants to observe a variety of advertisements for Republican presidential candidate, John McCain and Democratic presidential candidate, Barack Obama. It was discovered participants only reacted strongly to their preferred candidate and rarely responded to the advertisement of the rival candidate.

The study comprised of college students who were hooked up to electrodes that measure physiological response such as heart rate, skin conductance and muscle movement in the cheek bone and around the eyebrows. Researchers stated skin conductance, such as sweating, is related to how stimulated and alert an individual may or may not be.

Participants observed 12 campaign ads: six for Obama and six for McCain. The physiological responses demonstrated how each participant reacted emotionally to the content of the ad. Researchers stated a physiological response such as a lower heart is associated to an individual who is more attentive to the information in the ad, whereas a higher rate suggested the viewer is not focused.

According to lead study author Zheng Wang, assistant professor of communication at Ohio State University, partisan participants were inattentive to ads featuring the candidate they opposed. "If people are exposed to information in ads regarding a candidate they oppose, they respond by basically tuning out," Wang said.

Wang and colleagues used the dynamical feedback model to observe how ad factors interact with an individual's physiological reactions. If the individual support the particular candidate their positive feeling are intensified.

"At any one time, ad viewers' reactions are affected not just by what they are seeing at that exact moment, but also by what came before in the ad," Wang said. "The dynamical feedback model puts it all together to see how people react in a real-time, real-world way."

Additionally, research suggests individuals tend to be selective about what they are exposed to. Individuals are more likely to expose themselves to information that reinforces existing opinions.

Wang believes how people react to ads is a very complex process.

The study was published in the journal Communication Research.