A team of researchers from UCLA discovered that a group of sixth graders who didn’t use a phone, TV or computer for five days were much better at reading other people’s emotions correctly than a group of sixth graders who spent those five days engrossed with their phones and other electronic devices for their normal amount of time.

“Many people are looking at the benefits of digital media in education, and not many are looking at the costs,” Patricia Greenfield, a professor of psychology at UCLA and lead author of the study, said in a statement. “Decreased sensitivity to emotional cues — losing the ability to understand the emotions of other people — is one of the costs.”