Not having a go at Overnight but I was looking at something which discussed how the right in the US has become so phenomenally awful. I have to believe that when you are constantly being told you are wrong (and you are) but you are sure you are right, other areas of knowledge are affected.
In 2012 Fairleigh Dickinson University was first reported on these results. (still doing it https://view2.fdu.edu/publicmind/ )
Fox viewers knew less than people who watched no news at all.
"Researchers asked 1,185 random nationwide respondents what news sources they had consumed in the past week and then asked them questions about events in the U.S. and abroad.
On average, people correctly answered 1.6 of 5 questions about domestic affairs.
Because the aim of the study was to isolate the effects of each type of news source, they then controlled for variables such as other news sources, partisanship, education and other demographic factors.
They found that someone who watched only Fox News would be expected to answer 1.04 domestic questions correctly compared to 1.22 for those who watched no news at all. Those watching only "The Daily Show with Jon Stewart" answered 1.42 questions correctly and people who only listened to NPR or only watched Sunday morning political talk shows answered 1.51 questions correctly. "
