Writing at Psychology Today Blogs, Jennifer Latson explores how exposure to constant repetition can wear down skepticism, cater to credulousness, and foster falsehoods, so that truth gets lost. Here’s a bit (emphasis added):
The marketing term “effective frequency” refers to the idea that a consumer has to see or hear an ad a number of times before its message hits home. Essentially, the more you say something, the more it sticks in — and possibly on — people’s heads. It doesn’t even have to be true — and that’s the problem. What advertisers call “effective frequency,” psychologists call the “illusory truth effect”: the more you hear something, the easier it is for your brain to process, which makes it feel true, regardless of its basis in fact.
In her piece, she goes on to explore other human tendencies that make us susceptible to such subterfuge, while also pointing out that, in these days of digital deluges of dubious diatribes and a blatherscape of blaring botnets, staying aware of facts and identifying falsity is increasingly important.
I suggest “Fox News Effect” as shorthand for this phenomenon.