Many people on social networks know the feeling: They hop on Facebook for a few minutes, start looking at a friends’ vacation pictures and start scrolling through their newsfeed; before they know it, more than an hour has passed.

Some scientists suspect they know why: Users sometimes can slip into a state similar to what they call the machine zone—the almost hypnotic state gamblers sometimes fall into when they play slot machines.

In the machine zone, winning a jackpot becomes almost secondary. For players, it’s the repetition that matters: The push of the button, the lights, the sounds. Every pull of the handle leads to a slightly different, but still very familiar, result. The process is soothing to many, and gamblers can spend hours mesmerized by the machines—or until their quarters run out.

Social networks can trigger the same soothing sense of passive activity. Sometimes users don’t do much on Facebook or Instagram but look at pictures or updates while time seems to slip away.

“When we get wrapped up in a repetitive task on our computers, I think we can enter some softer version of the machine zone,” writes Alexis C. Madrigal for The Atlantic. “Obviously, if you’re engaged in banter with friends or messaging your mom on Facebook, you’re not in that zone. If you’re reading actively and writing poems on Twitter, you’re not in that zone. If you’re making art on Tumblr, you’re not in that zone. The machine zone is anti-social, and it’s characterized by a lack of human connection. You might be looking at people when you look through photos, but your interactions with their digital presences are mechanical, repetitive and reinforced by computerized feedback.” (The Atlantic)

Paul Asay has covered religion for The Washington Post, Christianity Today, Beliefnet.com and The (Colorado Springs) Gazette. He writes about culture for Plugged In and wrote the Batman book God on the Streets of Gotham (Tyndale). He lives in Colorado Springs with wife Wendy and his two children. Follow him on Twitter.