Based on the explosive popularity of handheld electronics, such as cellphones, I tease my kids that for job security, they should consider becoming a surgeon or physical therapist specializing in hands, specifically the thumb. But while I joke about the physical toll of cellphone use, I am concerned about the mental and emotional consequences of lives controlled by a slim brick of technology-the smartphone.

Cellphones are no longer just communication tools, but media and entertainment delivery platforms. Children use their phones to listen to music, take and share photos and videos, play games, watch TV, communicate silently with their friends and engage in social media. While the device allows them to access information and keep in touch, giving our kids a cellphone, iPod or tablet with Internet access is similar to giving them keys to a car-it exposes them to a world to which we will not always be privy, and that can sometimes be dangerous. Unlike with the drivers licensing process, our kids don't receive formal training, test-driving opportunities or a provisional license to learn how to be a responsible, respectful and safe cellphone operator. It's left to us parents to establish, enforce and model "rules of the road."

Keeping the Connection

While much is written about safety and security considerations with cellphones, child development experts recommend that parents also consider how portable electronic devices impact social skills and human connections. A 2013 study published in Psychological Science reports that electronic communication limits our biological capacity to connect with other people by reducing our neuroplasticity, which depends on "live experiences" that are proven to help mold us as human beings.

We might purchase a cellphone for our children initially so that we can keep in touch with them but, ironically, once they get a cellphone, our children spend less time interacting directly with us and with others. According to the longitudinal survey conducted by the Kaiser Family Foundation in 2010, nearly half of young people who own a cellphone spend no time talking to someone on the phone in a typical day, while spending an average of 90 minutes texting each day.

What can parents do to encourage more human interaction? Setting limits that allow for more interpersonal connection can help; these might include establishing "electronic-free zones" during meal times and brief car rides and nighttime "electronic curfews." "Having my girls unplug for car rides of under 20 minutes gave us the space to engage in some wonderful, old-fashioned conversation that we wouldn't have had if their phones or iPods were on," says Cheri Nolan, a Washington mother of two daughters.

Of course, as in all things parenting, our actions speak louder than our limits. Talking with other parents at our children's activities rather than constantly checking our email or Facebook page benefits our own brains and models human interaction. Going to the door to pick up a child from a friend's house rather than texting them when we pull into the driveway is another example. "I understand we're all in a hurry, but it's nice if parents occasionally come to the door to say 'Hello' and 'Thank you,'" says one Rockville mother of three.

While it can be much easier for my kids to text me to ask permission to do something, I often respond with my personal acronym of NATC-Not A Text Conversation. This might be because I have concerns about the activity in question or because my thumbs are tired, but often it is simply because I want to hear my child's voice. They know once they read "NATC" that an old-fashioned phone call is required.

Everyday interpersonal moments also get lost when there is too much focus on the screen. Teaching our kids to put their device away when making a retail purchase so that they can look the clerk in the eye and engage in pleasantries will increase the number of those necessary "live experiences." Also, we need to remind our kids to be present where they are and to whom they are with rather than worrying about what others are doing elsewhere. One Silver Spring mom, when kids come over to play, has them check their phones at the door. "The parents know to call the home phone if they need to reach their child, but I want the kids to spend time focusing on one another and not on their phones," she says.

Playing It Safe

While parents can use privacy controls, wireless settings and other cellphone services to protect and limit kids, these don't replace a parent's watchful eye and concern. Experts say we need to talk frankly and repeatedly with our kids about privacy controls and remind them how nothing in cyberspace ever really goes away, even when software companies promise it does. Before hitting "send" or "post," our kids need to ask themselves, "Would I say or show this in person?" and "How would I feel if their parent or other adult were to read this?" "What sex education used to be, it's now the 'technology talk' we have to have with our kids," says Rebecca Levey, blogger and operator of KidzVuz.com, a tween video review site.

Handheld electronic devices certainly are tied into our daily lives and offer many benefits. Understanding what limits parents need to set and, just as important, what actions we should model with our own device usage, can go a long way toward ensuring that our kids' lives are enhanced by technology rather than controlled by it.