This report of the research smells like bullshit (in the technical sense of communicating without reference to the truth), so I'm going to look into the research itself. Here are some indications that something is wrong.
Fundamentalist groups generally oppose anything that questions or challenges their beliefs or way of life.
Actually, nearly everyone does. Humans aren't exactly known for their tolerance of humans from other tribes, or for information that disagrees with them. In fact, only a minority of people
who like science will choose to read
science articles that might challenge their beliefs. (Results of a study; can't be arsed to go find it.)
For this reason, they are often aggressive towards anyone who does not share their specific set of supernatural beliefs, and towards science, as these things are seen as existential threats to their entire worldview.
Research on collective narcissism suggests that everyone with worldviews built on unstable group beliefs is aggressive toward anyone or anything that threatens to disconfirm them. For example, I see this in my own research area, directed at recent successes in artificial intelligence.
Based on previous research, the experimenters predicted that the prefrontal cortex would play a role in religious fundamentalism, since this region is known to be associated with something called ‘cognitive flexibility’. This term refers to the brain’s ability to easily switch from thinking about one concept to another, and to think about multiple things simultaneously. Cognitive flexibility allows organisms to update beliefs in light of new evidence, and this trait likely emerged because of the obvious survival advantage such a skill provides.
This comes off as weird because the most cognitively inflexible people in the world are autistic, and most autists are atheists. At very least, there's a lot more going on than inflexibility.
To investigate the cognitive and neural systems involved in religious fundamentalism, a team of researchers—led by Jordan Grafman of Northwestern University—conducted a study that utilized data from Vietnam War Veterans that had been gathered previously.
It's a terrible idea to try to generalize findings made with this data to the general population. The very most we could responsibly say is that the findings warrant further research using a more representative sample.
Diving back into the report now...
Learn to doubt the stories you tell about yourselves and your adversaries.