Unintended Consequences

It's always kinda funny to learn that something people do in order to achieve a certain effect not only fails to do that but in fact turns out to have the opposite one. Here are a couple examples... From an article titled "Persistence of Myths Could Alter Public Policy Approach" by Shankar Vedantam in the Washington Post:

The federal Centers for Disease Control and Prevention recently issued a flier to combat myths about the flu vaccine. It recited various commonly held views and labeled them either "true" or "false." Among those identified as false were statements such as "The side effects are worse than the flu" and "Only older people need flu vaccine." When University of Michigan social psychologist Norbert Schwarz had volunteers read the CDC flier, however, he found that within 30 minutes, older people misremembered 28 percent of the false statements as true. Three days later, they remembered 40 percent of the myths as factual. Younger people did better at first, but three days later they made as many errors as older people did after 30 minutes. Most troubling was that people of all ages now felt that the source of their false beliefs was the respected CDC. The psychological insights yielded by the research, which has been confirmed in a number of peer-reviewed laboratory experiments, have broad implications for public policy. The conventional response to myths and urban legends is to counter bad information with accurate information. But the new psychological studies show that denials and clarifications, for all their intuitive appeal, can paradoxically contribute to the resiliency of popular myths.

The article suggests that this phenomenon may play a role in commonly-believed misinformation like Saddam Hussein was directly involved in planning 9/11, that the destruction of the WTC was a controlled demolition and not the work of Arab terrorists; that 4,000 Jews working there had been warned to stay home that day, that the Pentagon was struck by a missile rather than a plane, etc. The explanation:

...repetition seems to be a key culprit. Things that are repeated often become more accessible in memory, and one of the brain's subconscious rules of thumb is that easily recalled things are true.

The experiments...illustrate another basic property of the mind -- it is not good at remembering when and where a person first learned something. People are not good at keeping track of which information came from credible sources and which came from less trustworthy ones, or even remembering that some information came from the same untrustworthy source over and over again. Even if a person recognizes which sources are credible and which are not, repeated assertions and denials can have the effect of making the information more accessible in memory and thereby making it feel true...

...for a substantial chunk of people, the "negation tag" of a denial falls off with time.

What to do?

...rather than deny a false claim, it is better to make a completely new assertion that makes no reference to the original myth. Rather than say, as Sen. Mary Landrieu (D-La.) recently did during a marathon congressional debate, that "Saddam Hussein did not attack the United States; Osama bin Laden did," Mayo said it would be better to say something like, "Osama bin Laden was the only person responsible for the Sept. 11 attacks" -- and not mention Hussein at all. The psychologist acknowledged that such a statement might not be entirely accurate -- issuing a denial or keeping silent are sometimes the only real options. So is silence the best way to deal with myths? Unfortunately, the answer to that question also seems to be no. Another recent study found that when accusations or assertions are met with silence, they are more likely to feel true

The second example is from an article titled "'Baby Einstein': a bright idea?" by Amber Dance in the LA Times:

For every hour a day that babies 8 to 16 months old were shown such popular series as "Brainy Baby" or "Baby Einstein," they knew six to eight fewer words than other children, the study found.

Christakis said children whose parents read to them or told them stories had larger vocabularies. "I would rather babies watch 'American Idol' than these videos," Christakis said, explaining that there is at least a chance their parents would watch with them - which does have developmental benefits.