I remember being blown away by the book Influence by Robert Cialdini. One of the aspects discussed in it was how authority in any form or shape (ranging from just wearing a suit to an officially appointed position) can have an impact when it comes to influencing and convincing people. What the book didn’t explain was why that effect was present.
I ran into this article that perhaps does do just that. It seems that people who are consistently (a term also extensively discussed in the book Influence) involved and devoted to a cause or a group, tend to unconsciously deactivate certain parts of their brain when listening to a figure from that movement or group. And it is exactly these parts of the brain that are mainly responsible for the vigilance and skepticism when judging the truth and importance of what people say.
So, I suppose we should be careful judging figures we are devoted to, and taking decisions on account of what they say… Or…?