Spee Kosloff, a visiting assistant professor of psychology at Michigan State University, and colleagues suggest people are most likely to accept falsehoods -- consciously and unconsciously -- when subtle clues remind them that Obama is different from them due to race, social class or ideological differences.
Kosloff says these judgments are irrational.
"Careless or biased media outlets are largely responsible for the propagation of these falsehoods, which catch on like wildfire," Kosloff says in a statement. "And then social differences can motivate acceptance of these lies."
Kosloff and colleagues began their study prior to the 2008 presidential election. For the conscious trials, participants were shown false blog reports saying Obama, a Christian, is a Muslim or a socialist, or that 74-year-old Sen. John McCain, R-Ariz., who ran for president in 2008, is senile. The unconscious trials involved gauging how rapidly study subjects identified smear-relevant words such as "Muslim" or "turban" after Obama's name was presented subliminally.
The study, published in the Journal of Experimental Psychology: General, finds participants who supported McCain said there was a 56 percent likelihood Obama is a Muslim but once asked to fill out a form on their race, the likelihood jumped to 77 percent. Meanwhile, participants undecided about the candidates said there was a 43 percent chance McCain was senile, but that number jumped to 73 percent once they listed their own age on a card.
"In America, many people dislike Muslims so they'll label Obama as Muslim when they feel different from him," Kosloff says.