The impact of misinformation tends to last long. In other words wrong facts stick to the memory - no amount of subsequent corrections helps, researchers say. But it certainly helps perhaps to understand how human memory works.
The study by Assistant Professor Ullrich Ecker, Professor Stephan Lewandowsky and David Tang, School of Psychology, University of Western Australia, was first published last year in Memory & Cognition journal and is featured this month in another journal Scientific American
Professor Ecker said information that was initially thought to be correct, but later retracted or corrected, often continued to influence memory and reasoning.
"It occurs even if the retraction or correction is well remembered and is often referred to as 'the continued influence effect of misinformation'," Professor Ecker said.
"Our study investigated whether the continued influence of misinformation can be reduced by explicitly warning people at the outset that they may be misled."
The researchers found that a specific warning - giving detailed information about the continued influence effect - succeeded in reducing the continued reliance on outdated information but did not eliminate it.
"A more general warning - reminding people that facts are not always properly checked before information is disseminated - was even less effective," Professor Ecker said.
"While people have some ability to prevent undue reliance on misinformation, it still continues to affect their reasoning. So while such warnings could be routinely given to jurors in court, for example, or could be part of media education, they do not eliminate the effects of misinformation.
"Our memory is constantly connecting new facts to old and tying different aspects of a situation together, so that we may still automatically draw on facts we know to be wrong to make decisions later."
If eternal vigilance is the price of liberty it is also perhaps a safeguard against misleading information with all its undesirable consequences.