I know it will shock every reader of this blog to discover this, but this groundbreaking study proves what we've all known: Watching Fox News will make you stupid. Or keep you stupid. Or something. What it won't do is inform you. As Christian Finnegan pointed out to David Shuster on Countdown, Fox News' goal is not to inform, but to "provide light intellectual cover for the gut prejudices you already have."

Fairleigh Dickinson University conducted a poll of about 700 New Jersey residents. They adjusted the results for partisanship and came to the following conclusion:

Sunday morning news shows do the most to help people learn about current events, while some outlets, especially Fox News, lead people to be even less informed than those who say they don’t watch any news at all.

Wow, who could've guessed? I'll bet if they polled Fox News viewers today, they'd say pepper spray is a vegetable!

I found some of the underlying data more interesting than the conclusion.

But the real finding is that the results depend on what media sources people turn to for their news. For example, people who watch Fox News, the most popular of the 24-hour cable news networks, are 18-points less likely to know that Egyptians overthrew their government than those who watch no news at all (after controlling for other news sources, partisanship, education and other demographic factors). Fox News watchers are also 6-points less likely to know that Syrians have not yet overthrown their government than those who watch no news.

"Because of the controls for partisanship, we know these results are not just driven by Republicans or other groups being more likely to watch Fox News," said Dan Cassino, a professor of political science at Fairleigh Dickinson and an analyst for the PublicMind Poll. "Rather, the results show us that there is something about watching Fox News that leads people to do worse on these questions than those who don’t watch any news at all."

By contrast, some media sources have a positive effect on political knowledge. For example, people who report reading a national newspaper like The New York Times or USA Today are 12-points more likely to know that Egyptians have overthrown their government than those who have not looked at any news source. And those who listen to the non-profit NPR radio network are 11-points more likely to know the outcome of the revolt against Syrian President Bashar Al-Assad. However, the best informed respondents are those that watched Sunday morning news programs: leading to a 16-point increase in the likelihood of knowing what happened in Egypt and an 8-point increase in the likelihood of knowing what happened in Syria.

"Sunday morning news shows tend to spend a lot more time on a single issue than other news broadcasts, and they are less likely to degenerate into people shouting at each other," said Cassino. "Viewers pick up more information from this sort of calm discussion than from other formats. Unfortunately, these shows have a much smaller audience than the shouters.

Huh. Calm discussion works better than shouting? Another news flash. Also, I guess we know why Republicans are so anxious to defund NPR, since those people who listen to NPR tend to be more informed.

Also, this tidbit shouldn't be a surprise to anyone who pays attention:

Exposure to Sunday morning news shows helps respondents on this question: seeing these programs leads to an 11-point increase in the likelihood of getting the answer right. Listening to NPR also helps, but the biggest aid to answering correctly is The Daily Show with Jon Stewart, which leads to a 6-point decrease in identifying the [OWS] protestors as Republicans, and a 12-point increase in the likelihood of giving the correct answer.

"Jon Stewart has not spent a lot of time on some of these issues," said Cassino. "But the results show that when he does talk about something, his viewers pick up a lot more information than they would from other news sources."

As to Christian Finnegan's question about how long it takes for Fox News to fry a rational person's brain? I have an answer: About one week.