If there’s anything that cognitive psychology studies have made clear over the years, it’s that humans can be exceptionally gullible. With a little push, we’re prone to developing false beliefs not only about others, but about ourselves with equal prowess — and the results can be, well, hard to believe.
For example, a study in 2001 asked participants to rate the plausibility of having witnessed demonic possession as children and their confidence that they had actually experienced one. Later, the same participants were given articles describing how commonly children witness demonic possessions, along with interviews with adults who claimed to have witnessed possessions as children. After reading the articles, participants not only rated demonic possession as more plausible than they’d previously said, but also became more confident that they themselves had actually experienced demonic possession as children.
Another (less dramatic) study asked participants to rate the plausibility that they’d received barium enemas as children. As with the other study, participants were later presented with “credible” information about the prevalence of barium enemas among children, along with step-by-step procedures for administering an enema. And again, the participants rated the plausibility of having received a barium enema as children significantly higher than they had before.
A recent study in the journal Applied Cognitive Psychology wanted to determine the effect of prevalence information (information that establishes how commonly an event happens, making it seem more likely and therefore more self-relevant) on the development of false beliefs. Participants were asked to rate the plausibility of 10 events from 1 (not at all plausible) to 8 (extremely plausible), and how confident they were that they’d experienced each event from 1 (definitely did not happen) to 8 (definitely did happen). The events included a range of the highly plausible (I got lost in a shopping mall as a child) to the highly implausible (I was abducted by a UFO).
Two weeks later, participants were brought back and given information on four of the events they’d previously rated, all in the low-to-moderate plausibility range (no UFOs). The information included newspaper articles, third-person descriptions, and data from previous study subjects — all of which was designed to establish higher prevalence of the events.
The results: High prevalence information from all sources affected the development of false beliefs. In particular, participants given high prevalence information in false newspaper articles became more confident that they had actually experienced the events, testifying to the power of the printed word.
The takeaway here probably has a few prongs. First, we shouldn’t discount the possibility that we’re just as susceptible to developing false beliefs as anyone else walking around this planet. The brain is a superb miracle of errors and no one, except the brainless, is exempt. On the other hand, knowing that to be true is also the best preventative against chasing the make believe rabbit into his hole. A little error adjustment can go a long, long way.