Excessive exposure to digital media interferes with a child’s development.

If you’ve ever used a chat room, message board or social media site, you’ve probably been insulted by a stranger. These digital interactions aren’t meaningless: they have an impact on our socialization, especially children’s.

Children develop empathy by interacting with other people. According to the psychiatrist Dan Siegel, children aren’t born with empathy: they develop it as they mature. They build social skills and learn to understand each other’s emotions as they fight, play and make friends.

Spending a lot of time online disrupts this process. And if children spend too much time in the digital world, it can actually decrease their empathy.

A group of Stanford researchers did over 70 studies on this phenomenon with college students. They did a systematic review of their studies based on standard empathy tests and found that, between 1979 and 2009, empathy in US college students decreased by 40 percent.

The decline was particularly strong in the last ten years of that time frame, and technology was pinpointed as one of the main causes.

Overexposure to digital media doesn’t only make people less empathetic. The fast pace of the digital world also makes it harder for children to concentrate.

In 2006, the Kaiser Family Foundation conducted a survey of teenagers and found that those who did their homework on the computer were far less focused on their work. In fact, they spent at least two-thirds of their time doing something else entirely.

Digital media has a big impact on a child’s development. It’s making it harder for children to focus in school, and the rude comments you’ve seen online probably come from young people whose empathy has been stunted.