This Washington Post article contains conclusions that PR professionals, journalists and an informed public need to know about what they consume from the media. For example:

• “The research also highlights the disturbing reality that once an idea has been implanted in people’s minds, it can be difficult to dislodge.”
• “Denials inherently require repeating the bad information, which may be one reason they can paradoxically reinforce it. Indeed, 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.”
• “Many easily remembered things, in fact, such as one’s birthday or a pet’s name, are indeed true. But someone trying to manipulate public opinion can take advantage of this aspect of brain functioning. In politics and elsewhere, this means that whoever makes the first assertion about something has a large advantage over everyone who denies it later.”
• “Furthermore, a new experiment by Kimberlee Weaver at Virginia Polytechnic Institute and others shows that hearing the same thing over and over again from one source can have the same effect as hearing that thing from many different people — the brain gets tricked into thinking it has heard a piece of information from multiple, independent sources, even when it has not.”