The Default Mode Network of the Brain in a Modern Environment

The default mode of the brain is scanning for threats. That's what the brain is doing when it's not doing anything. We can be daydreaming if there are no threats, but we're also constantly scanning. And our brains just get fried and our decision making capabilities get fried. It's not like all of a sudden human beings found it difficult to make good decisions. This has always been the case, but it's become increasingly difficult.