Coloring books for adults are having a moment: According to Publishers Weekly, sales in 2015 soared above 1.5 million. Now there’s a new title in the mix. As neurobiologist Daniel Siegel, M.D., says in his introduction to Diana Dube’s book, coloring provides moments of stillness in busy, electronics-driven lives, becoming “one antidote to this common stress and modern madness.” We caught up with Dube, an early-childhood educator, by phone at her home in New York City.

Why has coloring become so popular with adults?

I think it’s popular because it’s calming and meditative. It’s also something that you did when you were a kid. That can be pretty fun and loosens you up a little bit. It’s also nostalgic. What I’ve noticed is that you get into that zone where your body just feels calm. You have to focus, but it’s not a conscious focus. It’s more of a physical focus.

How did Dan Siegel, a prominent researcher on neurobiology, come to write the introduction?

My wife is one of the vice presidents at Norton, and the publisher of the professional books division there. Dan Siegel was one of her authors. I had used his books for the thesis I wrote for graduate school, and I think he’s really a visionary, and such an innovative thinker. We were really hoping that Dan would write the introduction—and he was really into it.

What’s the best time to color?

I really subscribe to the theory that people have different body rhythms. For me, it would be something to do at night, as a calming activity that would relax me from my day. But I could see how some people would wake up, and coloring would be energizing.

Do you and your family color at home?

We have coloring nights. It’s fun, actually. And it’s nice, because we just sit around the table and color, and chat a little bit. It’s better than just zoning in front of the TV.

When you were little, were you a colorer?

I wasn’t a colorer so much as a drawer. It’s funny, but now that I have my book, I can see why people like it. Your mind just goes into another place where it doesn’t go often. We’re so used to being on our phones, to having our minds and brains being stimulated by something. It feels good to let your mind go and let your body do something instead.