On January 6, two of Apple’s biggest investors published an open letter calling on Apple and other high tech firms to do much more to protect the health of their youngest users. Citing studies showing that smartphones can have grave impacts on kids’ physical and mental well-being, the investors – California State Teachers’ Retirement System and JANA Partners LLC – have opened a major debate, asking tech companies to develop more controls on their products for their youngest users.

What is so bad about kids and smartphones? With more researchers look into the impact of smartphones and other technology on children, here are some recent results, as well as suggestions for what we can do when it comes to protecting kids from smartphone abuse.

Stunting Babies’ Brain Development

The harm that smartphones and other screens do to kids is particularly acute in babies whose brains are still developing. Psychologists call the first three years of a child’s life “the critical period” in brain development because the way that brains grow during these years becomes the permanent base upon which all future learning relies. Receiving information and cues from the real world around them helps babies form neural pathways that make their brains strong and healthy. Stimuli from screens, including tablets and smartphones, get in the way of brains’ normal development, overwhelming their still-developing minds with stimuli.

The damage from too much screen time can be permanent. “The ability to focus, to concentrate, to lend attention, to sense other people’s attitudes and communicate with them, to build a large vocabulary – all those abilities are harmed,” warns Dr. Aric Sigman, an associate fellow the British Psychological Society and a Fellow of Britain’s Royal Society of Medicine.

The ability to interact with other people, to empathize and read people’s feelings all have their foundations in babyhood. Spending time interacting with screens instead of human beings can permanently alter our children’s brain structures, making tasks like forming friendships and understanding the world around them much harder.

Harming Teens’ Brains

While older kids don’t experience the same sort of intense brain development as babies, kids’ and adolescents’ brains continue to develop and can be harmed by too much smartphone use.

The problem is that teenagers’ brains are very adaptable. The experience of using a smartphone, switching rapidly between many activities such as texting and using social media, is associated with lower levels of brain matter in teens’ anterior cingulate cortex, the region in our brains that is responsible for emotional processing and decision-making. Less brain matter in this area is associated with higher rates of depression and addiction.

Another part of our brains, the prefrontal cortex, is necessary for interpreting emotions and for focusing on tasks, and is also harmed by smartphone use. This part of our brains doesn’t fully develop until people’s mid-20s, and excessive smartphone use can get in the way of that. “During our teenage years,” explains Paul Atchley, a psychology professor at the University of Kansas, ”it’s important to train that prefrontal cortex not to be easily distracted. What we’re seeing in our work is that young people are constantly distracted, and also less sensitive to the emotions of others.”

Harder to Make Friends:

Given the changes smartphones make to developing brain’s ability to empathize with others, it’s no surprise that smartphone use is associated with difficulty in making friends.

For many teens, smartphones can become a crutch in difficult social situations. “When you’re with people you don’t know well or there’s nothing to talk about, phones are out more because it’s awkward,” one Connecticut high school senior explained to researchers.

Yet this “new normal” where smartphones are such a part of social interaction is dangerous, warns Brian Primack, Director of the Center for Research on Media, Technology and Health at the University of Pittsburgh. “There’s strong research linking isolation to depression, and time spent socializing with improved mood and well-being,” Dr. Primack explains. “If smartphones are getting between an adolescent and her ability to engage in and enjoy face-to-face interaction – and some studies suggest that’s happening – that’s a big deal.”

Smartphones and Depression in Kids

Indeed, heavy smartphone use is associated with higher rates of stress and depression in kids. One study conducted by the Center on Media and Child Health at the University of Alberta found that over the past three to five years, as smartphone use has skyrocketed, 90% of teachers report that the number of students with emotional challenges is increased; 86% of teachers report that the number of students with social challenges has gone up as well.

Many teachers blame smartphone use for these jumps. Kids used to go outside during lunch break and engage in physical activity and socialization. “Today, many of them sit all lunch hour and play on their personal devices,” one junior high teacher said.

[Read more on Aish.]