• How Growing Up In the Digital Age Impacts Young Minds

    Carl D. Marci on the Pitfalls of Plugged-In Children

    Ryan was four years old when he started unboxing toys on camera in 2015. A few years later—assisted by his mother, who left her job as a high school teacher to work with him full time—he was YouTube’s highest-earning star, of any age. He made a record-breaking $29.5 million in 2020, releasing daily videos that blur the line between entertainment and commerce. His channel, now called Ryan’s World, has generated more than 60 billion views. I found out about Ryan when my then-four-year-old son became enamored with the videos. As Ryan opened boxes and talked about new toys, he created a virtual space of limitless wonder for kids—including my own.

    Article continues below

    When it comes to children’s experiences, today’s media ecosystem is dramatically different from the one in which I grew up. In addition to multiple cable television networks with ad-supported children’s programming available around the clock, a proliferation of new online channels feature short, on-demand, “snackable” forms of amateur video.

    Plus, parents can download a variety of content from sources like Netflix and Amazon and play them on portable devices for their kids anytime and anywhere. In a sea of choice, young users move freely from channel to channel and device to device, from large screens to small ones, through an endless variety of professionally and not-so-professionally produced short-, medium-, and long-form content.

    The shift in content creation, from professional producers of television and film to amateurs online, is important. The popularity of so-called user-generated content on YouTube, TikTok, and other outlets is fueled by computer algorithms that curate and serve up videos tailored to the individual tastes of young users. These algorithms are so sophisticated that in some cases they reveal—arguably create—previously unknown markets, markets that producers and advertisers are eager to reach to capitalize on children’s surprising and peculiar preferences. Who could have predicted that Ryan’s toy reviews and unboxing videos would take off? The unboxing genre did not even exist before a few years ago.

    Research continues to show that most media exposure for children under three years of age produces no health benefits whatsoever and few if any educational ones

    These changes raise many questions. What is the impact of shifts in media consumption by young children—increasing the quantity of content consumed, from new and questionable sources, via more screens than ever before? How is this sort of media consumption affecting the developing brain, and what are the downstream consequences for our physical and mental health?

    Article continues below

    As I’ve noted before, there is not always fresh, directly relevant research available to answer such questions. The media landscape is rapidly evolving, and science is catching up. But we can still gain insights by extrapolating from prior research on traditional media and integrating those findings with the growing understanding of childhood brain development provided by neuroscience. As I detail in this chapter, the available research shows that our brains, and our children’s brains, are being rewired in ways that need to be examined. Before we proceed, however, it is important to raise some caveats, as there are several challenges inherent in interpreting decades of research on television and applying it to today’s media world.

    First, as noted, production and access happen differently in the new-media environment. In the not so distant past, video content was created and distributed by professionals and consumed at a particular time of day. Broadcasters set schedules that enabled parents and caregivers to limit children’s viewing to professionally produced content like Sesame Street.

    First aired in 1969, Sesame Street was intended to provide high-quality, research-driven learning content for children, in particular kids living in poverty. Such programming required scores of writers, producers, directors, and actors. The show’s success is undisputed. By contrast, today’s user-generated amateur content, often made with less admirable goals, is produced by small groups and individuals wherever their smartphones take them. Past studies of media consumption assumed a different kind of media content than adults and kids consume today.

    Second, availability and presentation have changed. This often-amateur content is accessible 24/7 on mobile devices that parents often have trouble monitoring (more on that below). Today our children frequently consume media unsupervised, and can watch what they want, when and where they want it. Screen sizes have also changed; TV screens have gotten bigger, but most screen time is spent with small, portable images thanks to smartphones and tablet computers.

    Early viewing habits stick with us, fostering potentially serious effects on social, emotional, and physical health across the lifespan

    Third, the way we engage with new media is not like the way we engage with old media. Traditional television offers a passive experience: someone else produces and directs an immersive audiovisual story that unfolds linearly, with a clear beginning, middle, and end. We follow along. This experience triggers what neuroscientists call bottom-up processing, which refers to the lower or subcortical networks of neurons in the brain driving the process.

    Article continues below

    This is very different from how we tend to engage with new media, particularly online or in apps, which are by nature more interactive and encourage more switching and skipping. New media therefore trigger more top-down processing, with the networks in the upper prefrontal cortex of the brain in charge. Users engaged in top-down processing become the coproducers of their experience, making choices and reacting continually over time.

    As young users shift their attention styles and behaviors with new media, they tend to consume more media in shorter bursts, obtaining more immediate emotional rewards. As we will see, these attentional habits and emotional experiences leave their mark on the underdeveloped prefrontal cortex that mediates them, potentially contributing to shorter attention spans and other consequences later in life.

    Fourth, a major contributor to shorter media attention spans is media multitasking, defined as the use of two or more media devices simultaneously or the use of one media device in conjunction with a separate task such as homework. Given the ubiquity and mobility of modern media, the rise of media multitasking should not surprise us. The massive rise in media multitasking has implications for our children and ourselves. It also challenges researchers to think differently about the work they do. Older research had no reason to account for media multitasking, making this a new area that we need to examine from multiple angles.

    Fifth, because small, mobile screens make it hard to tell exactly what our children are consuming, a lot of current research depends on questionnaires directed at parents and young users. This increases the likelihood that usage data will be subject to various kinds of bias, as people tend to both over- and underreport media use depending on how and when questions are asked. So it is important for researchers to integrate survey results with new methods to ensure accuracy.

    Fortunately, such methods do exist, and surveys remain useful. Indeed, surveys of parents and children even suggest that some research about traditional television viewing is still relevant and can complement emerging studies on the impact of new media. For instance, one well-designed survey finds that, despite the increase in use of portable computers and interactive apps, much of the mobile-phone content kids consume is in the form of entertainment video from YouTube and Netflix.

    Article continues below

    Finally, a problem that bedevils old- and new-media research alike is that even the most compelling correlations between behaviors and outcomes do not prove causation. We must therefore be careful not to interpret a relationship between two variables as evidence that one variable caused the other. For example, as we will see, children diagnosed with ADHD consume a lot of media and are especially given to media multitasking.

    But does this mean that children with ADHD gravitate toward excessive media consumption and media multitasking, or does excessive media consumption and media multitasking exacerbate or cause symptoms of ADHD? As we will see, the preponderance of evidence suggests there may indeed be a causal link. But that link cannot just be presumed. Proving it requires clever research design and careful analysis of results.

    The data showed that each hour of video content infants (age 8–18 months) watched per day was associated with a significant decrease in language acquisition

    Thankfully, we have plenty of rigorous, older research to draw on. Judiciously interpreted, it can and should inform today’s raging debate about the impact of screen time and mobile media use on children and adolescents. In particular, when paired with recent progress in our understanding of the implications of new media and related technologies on brain development, traditional media studies provide insights on what we should expect for children today as they grow into the adults of tomorrow.


    Julie Aigner-Clark was a stay-at-home mother and former high school English teacher. When her first daughter was about a year old, Aigner-Clark started to wonder whether there was a way to expose her to the arts and sciences. She looked around but found the marketplace for infant education lacking. So she decided to make her own curriculum. She borrowed a video camera and, with a few puppets plus the help of her husband, she shot her first film in her basement in 1996.

    It was the birth of a new concept in media as well as a company that would soon be famous across the United States: Baby Einstein. “Everything I did in the first videos was based on my experience as a mom,” she said in an interview. “I didn’t do any research. I knew my baby. I knew what she liked to look at. I assumed that what my baby liked to look at, most other babies would, too.”

    Article continues below

    The idea that you could expose children as young as six months of age to high culture and foreign languages through videos resonated with millions of parents. The first series, also called Baby Einstein, was followed by others including Baby Mozart, Baby Galileo, and Baby Shakespeare. The videos typically were simple montages of puppets, toys, and shapes set to music and poetry read aloud. Parents praised the videos and bragged that their children would sit quietly for hours, watching intently and apparently learning. Baby Einstein products won several awards, including a Best Video prize from Parenting magazine. At its peak, Baby Einstein’s videos were in nearly one-third of American households with children under two years of age.

    Success sparked competition. The UK program Teletubbies followed in 1998, as did others with fun and hopefully educational content. After a few years, Aigner-Clark herself wasn’t having much fun, facing the pressures of leading a growing business. She sold the company to Disney in 2001 for an undisclosed amount. The acquisition of Baby Einstein provides Disney with another high quality brand franchise which serves one of our core customer segments— families with small children,” Disney president Bob Iger explained.

    A few years later, however, things took a turn. A 2007 paper in the journal Pediatrics became the first in a series of research articles that questioned the educational impact of the infant videos. The researchers called more than a thousand parents of children age two or younger to survey them about their child’s viewing habits and administer a short version of a well-validated language test used to assess children’s early verbal skills.

    The results were not encouraging for the Baby Einstein franchise or for video exposure in infancy in general. The data showed that each hour of video content infants (age 8–18 months) watched per day was associated with a significant decrease in language acquisition. The impact was particularly strong in the youngest children. Not only were infants not learning language at a faster rate, but the evidence suggested that they were falling behind.

    In response to the research, Time magazine published a provocative and critical article entitled, “Baby Einsteins: Not So Smart After All.” Child-advocacy groups and the US Federal Trade Commission also questioned the validity of claims associated with the products. Under pressure, Disney dropped the word “educational” from its marketing. The company followed with an unprecedented offer to refund parents for some of their DVD purchases, a move that was interpreted as a tacit admission that the videos “were not producing Einsteins after all.”

    Researchers today point to four main reasons to be concerned about any television and video consumption by children prior to age three. First, recall that brain development is most pronounced in the first years after birth, so the interaction among genetics, neuronal growth, and environment is especially critical at this time. There is evidence that exposure to the bright lights and fast pacing of many child-oriented videos can lead to significant effects on attention and cognition. Even background television alters the way very young children play with toys and how parents interact with their children.

    Second, infants and toddlers cannot actually learn much from videos. Even if young children can grasp what is happening on a screen, they lack the cognitive skills to translate that information into knowledge that is meaningful in the three-dimensional world of reality. This so-called video-transfer deficit likely explains the educational failure of Baby Einstein and similar early-childhood audiovisual products. This deficit is probably related to the immature brain in general and the infantile prefrontal cortex in particular, an immaturity that results in poor attentional control, underdeveloped memory capabilities, and an inability to carry out abstract and symbolic thinking.

    Not only were infants not learning language at a faster rate, but the evidence suggested that they were falling behind.

    One of the key pieces of evidence for the video-transfer deficit is a 2010 randomized controlled study of vocabulary learning. Researchers recruited ninety-six families with children between twelve and eighteen months of age and assigned each child to one of four groups. One group watched a bestselling infant-learning DVD at least five times a week without a parent present. Another group watched the same video just as often but with a parent. The third group of kids was tasked with learning the same words only through interaction with their parents—no DVD. A fourth group served as a control and was not exposed to the words at all. The study lasted a month, and the children were tested on their knowledge of the words before and after the study period.

    The results clearly show that the toddlers exposed to the video learned no more words than did the control group, regardless of whether a parent was involved. The toddlers who were taught by their parents without the DVD showed the most learning. Interestingly, parents who joined in watching the DVD and reported that their kids enjoyed the video tended to overestimate how much their children had learned, which, again, was very little.

    The study makes plain that, when it comes to infant learning, videos are no substitute for face-to-face interaction. Adults who believe otherwise are assuming brain resources that don’t yet exist. Social interaction with parents did not effectively supplement video-based learning because, among toddlers, there just is no such thing as video-based learning.

    A third concern about viewing habits among the very young comes under the heading of the displacement hypothesis: time spent watching video potentially displaces other more age-appropriate activities such as face-to-face interactions, creative or open playtime, physical movement, outdoor play, and reading, all of which are known to foster brain health in kids. As noted, surveys suggest that some young children today are spending upward of three hours per day with media, an enormous proportion of their waking time spent not doing developmentally important tasks.

    Finally, early viewing habits stick with us, fostering potentially serious effects on social, emotional, and physical health across the lifespan. Early exposure wires young brains to cope with emotions and moods using media instead of through relationships and at the expense of much needed lessons in self-control. Habits are built over time and are influenced by emotionally rewarding stimuli that become harder to change as they become more firmly wired in the brain.

    As researchers Dimitri Christakis and Frederick Zimmerman put it, referring to just one kind of media, “The influence that television might play in this neuromaturational process should not be underestimated.”

    This influence can result in multiple negative effects that manifest as kids grow up: reduced executive function, mental health issues, higher rates of nearsightedness, and increased levels of obesity, which contributes to other physical health problems down the road. Meanwhile research continues to show that most media exposure for children under three years of age produces no health benefits whatsoever and few if any educational ones; there is simply no getting around the video-transfer deficit.

    These findings hold regardless of socioeconomic status. So unequivocal are the research results that the American Academy of Pediatrics (AAP) strongly discourages any media exposure for children under two years of age.


    Excerpted from Rewired: Protecting Your Brain In The Digital Age by Carl D. Marci, MD. Copyright Ⓒ 2022. Available from Harvard University Press.

    Carl D. Marci
    Carl D. Marci
    Carl D. Marci, M.D., a leader in the fields of social and consumer neuroscience, is Chief Medical Officer at Cava Capital and was formerly Chief Neuroscientist at the Nielsen Company. He also is on the faculty of Harvard Medical School and is a psychiatrist at Massachusetts General Hospital.

    More Story
    Kate Eichhorn on the Rise of Insta-Artists and Insta-Poets In April 2014, Amalia Ulman, a recent art school graduate living in Los Angeles, started to upload images of herself to Instagram....
  • Become a Lit Hub Supporting Member: Because Books Matter

    For the past decade, Literary Hub has brought you the best of the book world for free—no paywall. But our future relies on you. In return for a donation, you’ll get an ad-free reading experience, exclusive editors’ picks, book giveaways, and our coveted Joan Didion Lit Hub tote bag. Most importantly, you’ll keep independent book coverage alive and thriving on the internet.