With the 2008 presidential election only a year away, the merits of each candidate are becoming a common topic of conversation. But how do our brains, after hearing so many different opinions, gauge the popularity of each one? New research findings suggest that we judge a viewpoint's prevalence by how familiar it is—regardless of whether we have heard it five times from one person or once each from five different people.
Kimberlee Weaver, a psychologist at Virginia Polytechnic University, and her colleagues gave volunteers records of opinions from a fictional focus group that had supposedly met to discuss the preservation of open space in New Jersey. In some cases, multiple people expressed the viewpoints; in others, the same person repeated an opinion many times. Based on these records, they asked the subjects to estimate how the focus group, and the population in general, felt about the matter.