Along the lines of a study on the effects of advertising that I mentioned earlier, a forthcoming University of Kent study suggests that people are more influenced by conspiracy theories than they think they are, and that this hidden influence may actually contribute to the tenacity of such theories:
After reading internet-based conspiracy theories about the death of Princess Diana, research participants agreed more strongly with statements such as ‘there was an official campaign by MI6 to assassinate Diana, sanctioned by elements of the establishment’. When asked how much they would have agreed with those statements prior to reading the conspiracy theories, they ‘revised’ their prior attitudes so that they were closer to their current attitudes – this made it appear as though their attitudes had changed less than they actually had.
…Our findings suggest that conspiracy theories may actually have a ‘hidden impact’, meaning that they powerfully influence people’s attitudes whilst people do not know it; outwardly they may deny the extent to which they have been influenced but in truth they tend to endorse the new information and pass it on to others.’
(Link via Cognitive Daily.)