Smart phones are a big part of life in America, but for most students across the country, they will not be a part of the school day. More than half of U.S. states have some form of a ban on smart phones during the school day, including New York state, with more laws pending across the country. The move highlights growing concern over the distraction of such technology as well as the mental health impact these devices may have on kids.

Health experts agree cell phones can be addictive and distracting in the classroom, but parents may also want to think twice about the phone at home too, especially close to bedtime.

The American Academy of Pediatrics recommends children ages 3-5 years get 10 to 13 hours of sleep including naps, children ages 6-12 years old get 9-12 hours of sleep and children 13-18 years get 8-10 hours of sleep.

Cell phones disrupt sleep in several ways. The most common disruptor of sleep from cell phones and other electronic devices is from the blue light emitted. “Blue light tricks your brain into thinking it’s still daytime,” said sleep medicine physician and developmental neurologist, Georges Ghacibeh, M.D.. “The blue light suppresses the release of melatonin, the key hormone your body produces to make you feel sleepy and prepare for rest. Without enough melatonin, you’ll find it harder to fall asleep, and the quality of your sleep will be worse.”

Sleep experts say children should practice good sleep habits such as making the bedroom a screen time free zone at bedtime. Blue light from cell phones, televisions and computers can disrupt sleep. Back to school is a good time to create a media plan designed to balance screen time with sleep, exercise and other healthy activities.

But it’s not just the blue light from a cell phone that is disrupting sleep, it’s the addiction to the phone caused by the dopamine the phone often provides.

“Many students’ lack of sleep is directly related to the overuse of phones and social media and video games,” says Dr. Ghacibeh. “The addictive nature of seeking more comments and likes, have them repeatedly checking their phone, going to bed late, waking up early and in many cases waking up in the middle of the night looking for more validation from the phone.”

Dopamine or the anticipation hormone is released not when you get an award but in anticipation of a potential reward, making the phone a dopamine vending machine. “Each buzz, a ping, a red badge—is a potential reward. It could be a text from a friend, a ‘like’ on your photo, a breaking news alert, or a funny video,” Dr. Ghacibeh says. “Your brain releases a small hit of dopamine, motivating you to check your phone to see what the reward is. This creates a powerful loop between the phone’s buzz, the anticipation, the reward and the anticipation of the next one, making the habit hard to break, even when it’s time to go to sleep.”

The intermittent nature of the rewards on the cell phone is also addictive, like a slot machine where you don’t know what is going to come up next. If you received a reward every time you looked at your phone, it would be less pleasurable, but because you never know when you will, the phone has you repeatedly checking for your next validation.

Additionally, platforms like YouTube, TikTok, and Instagram don’t just show you random content. They use powerful algorithms to learn exactly what you like and feed you a perfectly tailored stream of content designed to keep you engaged for as long as possible. The phone “gets to know you” and becomes better and better at holding your attention.

Phones aren’t going away and when used correctly are a valuable tool. The key is to learn to limit use, recognize the signs of addiction and how to break the cycle. Parents should think twice about giving phones to young children who have less control over their own impulses. Use phone tools like “do not disturb” and “sleep mode” to help you focus on school work and sleep. Do not bring the phone into your bedroom at night, keep it far away until morning, and stop using it several hours before bedtime to allow for undisturbed sleep.