Many people try to limit the time they spend on social media when they’re with their kids. But new research suggests social media use has a significant effect on interactions with children — even when adults aren’t looking at their screens.

Mothers who were in the habit of spending more time on social media talked much less to their kids when they played with them than did moms who spent less time on social networks, and that difference carried over when they weren’t using their devices, according to a study to be presented Tuesday at the Digital Media and Developing Minds International Scientific Congress in Washington, DC.

While past research has focused on how kids are affected when parents or guardians are on their screens, this study looked at the impact of cell phone use on parent-child interactions even when parents were offline, said Liz Robinson, a doctoral student at the University of Alabama in Tuscaloosa and lead author of the study.

Mothers who used social media extensively spoke 29% less to their kids while playing with them — without their phones — compared with the moms whose social media use was low. Moms in the low-use category used social media an average of 21 minutes per day, while moms in the high-use category used social media an average of 169 minutes per day.

Other uses of screens, including checking email or the weather, weren’t associated with talking less to kids, according to the study of 65 toddlers ages 2 through 5 years old and their mothers in Alabama.

Although Robinson’s research has not yet been peer-reviewed or published in a journal, it doesn’t surprise me. In my own research, people often say they still think about what they see on social media long after they log off. Although the moms in this study were physically present with their kids, it’s possible their minds were elsewhere.

“Often our minds wander to activities that are more pleasurable naturally, and we know social media is that experience for most people,” said Kris Perry, executive director of Children and Screens: Institute of Digital Media and Child Development, a nonprofit to help kids lead healthy digital lives and the organizer of the Congress.

Perry, who was not involved in the research, pointed out that social networks show us tailored content that is intensely interesting to us, so “it makes you want to experience it longer.”

Whatever the reason, kids need their parents to be mentally present when they play. Thankfully, there are things we can do to make sure our social media use doesn’t interfere with our parenting.