Why the news is so negative — and what we can do about it

In Broadcast News, the movie that made me want to be a journalist, the protagonist Jane Craig (Holly Hunter) has a routine every morning. At an appointed time, she sits and weeps profusely for a minute. When the minute’s done, she wipes her face and goes about her day without showing outward signs of sadness.

Journalists have always been a fairly morose bunch, and the news they produce reflects that. Communications scholars have found that across many years and countries, coverage of political topics tends to more often be conveyed in a negative or...