Joe Pierre has posted two pieces about the psychology of conspiracy theories (and theorists) at Psychology Today Blogs, derived from a radio interview in which he participated. They are worth a look.
Here’s a bit from Part One (emphasis added):
How has the internet affected the spread of conspiracy theories? Do you think the internet promotes the spread of conspiracy theories?
There’s little question that the internet can help spread false beliefs including conspiracy theories. And research has shown that misinformation tends to spread faster and more widely than factual information. So the internet is clearly a fertile breeding ground for conspiracy theories.
That said, there is not good evidence that conspiracy theories are necessarily more common now than they have been at other points in history. . . .
What is somewhat unique to the internet is the way it’s very design — through a click-based revenue model along with the creation of filter bubbles — can foster echo chambers and confirmation bias that strengthens conviction in our pre-existing beliefs. As I like to say, searching for information online is often like “confirmation bias on steroids.”