I have written often about paranoia, right from the start, and you can get more detail by entering that word on my search bar.
I have a new and interesting update. One of my claims is that the paranoia strikes the brain first - both in the psychotic illnesses and in the milder political forms of paranoia - and the human then goes in search of the explanation. Feeling precedes data. The paranoid is sure that "something is up," and tends to draw on whatever culture floats his way after that. Thus the focus of the paranoia can change, albeit very slowly, over time.
I have a favorite story about a patient who came in around 2007, complaining that everything had been going fine until the government implanted that chip in his head after the First Gulf War. I called his family and community providers to get some background information. His mother told me everything had been fine until the government had implanted that chip in his head after the First Gulf War.
That's when I knew it was going to be a long day.
The patient and his family were involved at the edges in a few paranoid causes - the Ed Brown Tax-Protest standoff, for example - but had been rejected by nearly all because he was just too crazy and threatening for them. When the people who are into colonics as an adjunct to their dentistry find you too ill...
His case is fascinating in itself, and I could disguise the information well enough to protect his confidentiality (far better than he protects it himself), but that's not my point. He was brought back to the hospital, accompanied by a different group of visitors who come in and mutter with him now. His mother is still part of the mix, but the rest of the crowd has changed. He is still paranoid, and has a theory about why he was brought in now, involving powerful forces arrayed against him that he is going to expose - but no more implanted chip. Now the story is that Special Forces subjected him to brain experiments while he was in Iraq, and the government has been trying to silence him with "state-sponsored terrorism" ever since. Similar, but not the same. There has been a migration in the delusion.
His mother has also dropped the chip idea. She now hears "them" talking about her son from all over America when she is on conference call every night. The other visitors come from categories of believing other paranoid things about the government* or other world forces, and have concluded that if my patient is being so persecuted, then he must be very near the center of this whole battle, and what he says must therefore be correct, and they should get involved with his battle against the state because clearly, important things ride on it.
That this is entirely circular they cannot accept. If you tell them that the patient's condition is not that uncommon, his symptoms not that unusual, and the whole thing rather small, they take it as proof that it is big - because clearly the hospital is trying to hide something. You can refresh your memory on anosognosia if you wish by throwing in that search term up top as well.
*The breakdown seems to be about one-third sounding rather right-wing/libertarian, a few sounding very green/WTO left, but most caught up in their own personal persecution by the various towns they live in.