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 Have any such brain differences been found? 
 
 Not convincingly. More than 100 scientific reports and surveys have studied screen habits and well-being in young people, looking for emotional and behavioral differences, as well as changes in attitude, such as in body image. In 2014, scientists from Queen’s University Belfast reviewed 43 of the best designed such studies. The studies found that social networking allows people to broaden their circle of social contacts in ways that could be both good and bad, for instance by exposing young people to abusive content. The review’s authors concluded that there was “an absence of robust causal research regarding the impact of social media on the mental well-being of young people.” In short: results have been mixed, and sometimes contradictory. 
 
 Psychologists have also examined whether playing violent video games is connected to aggressive behavior. More than 200 such studies have been carried out; some researchers found links, others have not. One challenge in studying this and other aspects of screen time is identifying the direction of causality: Do children who play a lot of violent video games become more aggressive as a result, or were they drawn to such content because they were more aggressive from the start? 
 
 Even if scientists found strong evidence of a single, measurable effect — if, say, three hours of daily screen time was associated with a heightened risk of being diagnosed with A.D.H.D. — such a clear association wouldn’t necessarily suggest there were any consistent, measurable differences in brain structure. 
 
 Individual variation is the rule in brain development. The size of specific brain regions such as the prefrontal cortex, the rate at which those regions edit and consolidate their networks, and the variations in these parameters from person to person make it very difficult to interpret findings. To address such obstacles, scientists need huge numbers of research subjects and a far better understanding of the brain. 
 
 Isn’t that what the N.I.H. study aims to address? 
 
 Yes. The ongoing A.B.C.D. study expects to follow 11,800 children through adolescence, with annual magnetic resonance imaging, to see if changes in the brain are linked to behavior or health. The study began in 2013, recruiting 21 academic research centers, and initially focused on the effects of drug and alcohol use on the adolescent brain. Since then, the project has expanded, and now includes other targets such as the effects of brain injury, screen time, genetics, and an array of “other environmental factors.” ||||| The American Academy of Pediatrics now recommends parents "avoid digital media use -- except video chatting -- in children younger than 18 to 24 months" 
 
 Researchers have found "different patterns" in brain scans among children who record heavy smart device and video game use, according to initial data from a major ongoing US study. 
 
 The first wave of information from the $300 million National Institute of Health (NIH) study is showing that those nine and 10-year-old kids spending more than seven hours a day using such devices show signs of premature thinning of the cortex, the brain's outermost layer that processes sensory information. 
 
 "We don't know if it's being caused by the screen time. We don't know yet if it's a bad thing," said Gaya Dowling, an NIH doctor working on the project, explaining the preliminary findings in an interview with the CBS news program 60 Minutes. 
 
 "What we can say is that this is what the brains look like of kids who spend a lot of time on screens. And it's not just one pattern," Dowling said. 
 
 The NIH data reported on CBS also showed that kids who spend more than two hours a day on screens score worse on language and reasoning tests. 
 
 The study -- which involves scanning the brains of 4,500 children -- eventually aims to show whether screen time is addictive, but researchers need several years to understand such long-term outcomes. 
 
 "In many ways, the concern that investigators like I have is, that we're sort of in the midst of a natural kind of uncontrolled experiment on the next generation of children," Dimitri Christakis, a lead author of the American Academy of Pediatrics' most recent guidelines on screen time, told 60 Minutes. 
 
 Initial data from the study will begin to be released in early 2019. 
 
 The academy now recommends parents "avoid digital media use -- except video chatting -- in children younger than 18 to 24 months." ||||| WARCZone is a collection of outsider-uploaded WARCs, which are contributed to the Internet Archive but may or may not be ingested into the Wayback Machine. They are being kept in this location for reference and clarity for the Wayback Team, while also being accessible to the general public who are seeking any particular items they can regarding certain websites. ||||| The first data from a decade-long study of the effects of screen time on more than 11,000 American children by the National Institutes of Health shows that those who spent more than two hours each day on screens scored lower on thinking and language tests, according to a report from CBS' "60 Minutes." 
 
 The big picture: In extreme cases, researchers also said that some brain scans of 9- and 10-year-olds who spend more than seven hours a day using electronic devices show a thinning of the brain's cortex, which usually happens later in development. It's worth noting these are early results that have not yet been published in a peer-reviewed journal, so they shouldn't be viewed as definitive. As the NIH's Dr. Gaya Dowling told "60 Minutes," "We don't know if it's being caused by the screen time. We don't know yet if it's a bad thing." ||||| If you have kids and wonder if all that time they spend on their smartphones endlessly scrolling, snapping and texting is affecting their brains, you might want to put down your own phone and pay attention. The federal government, through the National Institutes of Health, has launched the most ambitious study of adolescent brain development ever attempted. In part, scientists are trying to understand what no one currently does: how all that screen time impacts the physical structure of your kids' brains, as well as their emotional development and mental health. 
 
 At 21 sites across the country scientists have begun interviewing nine and ten-year-olds and scanning their brains. They'll follow more than 11,000 kids for a decade, and spend $300 million doing it. Dr. Gaya Dowling of the National Institutes of Health gave us a glimpse of what they've learned so far. 
 
 Dr. Gaya Dowling: The focus when we first started talking about doing this study was tobacco, marijuana, all drugs the screen time component really came into play because we were wondering what is the impact? I mean, clearly kids spend so much time on screens. 
 
 The first wave of data from brain scans of 4,500 participants is in and it has Dr. Dowling of the NIH and other scientists intrigued. 
 
 The MRI's found significant differences in the brains of some kids who use smartphones, tablets, and video games more than seven hours a day. 
 
 "We're sort of in the midst of a natural kind of uncontrolled experiment on the next generation of children." 
 
 Dr. Gaya Dowling: What we can say is that this is what the brains look like of kids who spend a lot of time on screens. And it's not just one pattern. 
 
 Anderson Cooper: That's fascinating. 
 
 Dr. Gaya Dowling: It's very fascinating. 
 
 The colors show differences in the nine and ten-year-olds' brains. The red color represents premature thinning of the cortex. That's the wrinkly outermost layer of the brain that processes information from the five senses. 
 
 Anderson Cooper: What is a thinning of the cortex mean? 
 
 Dr. Gaya Dowling: That's typically thought to be a maturational process. So what we would expect to see later is happening a little bit earlier. 
 
 Anderson Cooper: Should parents be concerned by that? 
 
 Dr. Gaya Dowling: We don't know if it's being caused by the screen time. We don't know yet if it's a bad thing. It won't be until we follow them over time that we will see if there are outcomes that are associated with the differences that we're seeing in this single snapshot. 
 
 Dr. Gaya Dowling 
 
 The interviews and data from the NIH study have already revealed something else: kids who spend more than two hours a day on screens got lower scores on thinking and language tests. 
 
 Anderson Cooper: When the study is complete, is it possible that a researcher will be able to say whether or not screen time is actually addictive? 
 
 Dr. Gaya Dowling: We hope so. We'll be able to see not only how much time are they spending, how they perceive it impacting them, but also what are some of the outcomes. And that will get at the question of whether there's addiction or not. 
 
 Anderson Cooper: When will you have the answers that you're searching for? 
 
 Dr. Gaya Dowling: Some questions we'll be able to answer in a few years. But some of the really interesting questions about these long-term outcomes, we're gonna have to wait awhile because they need to happen. 
 
 That delay leaves researchers who study technology's impact on very small children anxious. 
 
 Dr. Dimitri Christakis: In many ways, the concern that investigators like I have is that we're sort of in the midst of a natural kind of uncontrolled experiment on the next generation of children. 
 
 Dr. Dimitri Christakis at Seattle Children's Hospital was the lead author of the American Academy of Pediatrics' most recent guidelines for screen time. They now recommend parents, "avoid digital media use, except video chatting, in children younger than 18 to 24 months." 
 
 "Toddlers need laps more than apps" 
 
 Dr. Dimitri Christakis: So what we do know about babies playing with iPads is that they don't transfer what they learn from the iPad to the real world, which is to say that if you give a child an app where they play with virtual Legos, virtual blocks, and stack them, and then put real blocks in front of them, they start all over. 
 
 Anderson Cooper: If they try to do it in real life, it's as if they've never done it before. 
 
 Dr. Dimitri Christakis: Exactly. It's not a transferable skill. They don't transfer the knowledge from two dimensions to three. 
 
 Dr. Christakis is one of the few scientists who have already done experiments on the influence screens have on children under the age of two. It's a critical period for human brain development. 
 
 Dr. Dimitri Christakis: If you're concerned about your teenager being addicted to their iphone, your infant is much more vulnerable and using the exact same device. 
 
 Anderson Cooper: Your infant is more vulnerable because why? 
 
 Dr. Dimitri Christakis: Because the experience of making something happen is so much more gratifying to them. 
 
 In a small pilot study that Dr. Christakis conducted on 15 children, researchers gave toddlers three toys: first a plastic guitar, then an iPad that played musical notes and finally an iPad with an app that rewarded the kids with lights, colors and sounds. 
 
 Dr. Dimitri Christakis: So at a very specific time, the research assistant will ask the child to give what they're playing with back. 
 
 Anderson Cooper: To give it to the research assistant. 
 
 Dr. Dimitri Christakis: To give it to the research assistant. 
 
 Sixty-six percent of the time with a traditional toy, the child will do just that. 
 
 Dr. Dimitri Christakis: With the iPad that simulates that, they give it back almost with the same frequency. But with the iPad app that when they push on it, it does all kinds of things, they're much less likely to give it back. 
 
 With the more interactive iPad app, the percentage of kids willing to hand it back to the researcher dropped from 60 percent to 45 percent. 
 
 Anderson Cooper: It's that much more engaging? 
 
 Dr. Dimitri Christakis: It's that much more engaging. And that's what we find in the laboratory. 
 
 It's engaging by design, as Tristan Harris told us in a story we reported more than a year ago. 
 
 Tristan Harris: There's a whole playbook of techniques that get used to get you using the product for as long as possible. 
 
 Harris is a former Google manager who was one of the first Silicon Valley insiders to publicly acknowledge that phones and apps are being designed to capture and keep kids' attention. 
 
 Tristan Harris: This is about the war for attention and where that's taking society and where that's taking technology. 
 
 Anderson Cooper: You know it's one thing for adults, for kids this is a whole other thing? 
 
 Tristan Harris: That is where this gets particularly sensitive…is developmentally do we want this war for attention to be affecting our children? 
 
 Anderson Cooper: Do you think parents understand the complexities of what their kids are dealing with? 
 
 Tristan Harris: No. And I think this is really important. Because there's a narrative that, oh, I guess they`re just doing this like we used to gossip on the phone, but what this misses is that your telephone in the 1970s didn't have a thousand engineers on the other side of the telephone who were redesigning it to work with other telephones and then updating the way your telephone worked every day to be more and more persuasive. 
 
 Until recently, it was impossible to see what happens inside a young brain when a person is focused on a mobile device. But now scientists at the University of California, San Diego have hacked that problem. 
 
 Correspondent Anderson Cooper speaks with Dr. Kara Bagot 
 
 Dr. Kara Bagot is an investigator on that $300 million NIH study. Her team is scanning teenager's brains as they follow Instagram, the most popular social media app. When we met 18-year-old Roxy Shimp, she was about to participate in Dr. Bagot's study. 
 
 Anderson Cooper: How much time do you actually spend on screens? 
 
 Roxy Shimp: I check my phone pretty regularly I'd say. 
 
 Anderson Cooper: What's pretty regularly? 
 
 Roxy Shimp: Every at least 10 to 20 minutes. 
 
 Anderson Cooper: Is that a conservative estimate? 
 
 Roxy Shimp: Probably. 
 
 She can't take her phone into the MRI because of the powerful magnets in the machine, so a mirror has been placed above her face to allow her to look across the room at a movie screen displaying images from her Instagram account. This way, Dr. Bagot can see exactly which parts of the brain's reward system are most active while using social media. 
 
 Anderson Cooper: So you can actually see a part of the brain light up when you're feeling good. 
 
 Dr. Kara Bagot: Yes, in the scanner. 
 
 Anderson Cooper: In the scanner. 
 
 Based on her data and the results from other studies, Dr. Bagot is among scientists who believe screen time stimulates the release of the brain chemical dopamine, which has a pivotal role in cravings and desire. 
 
 Dr. Kara Bagot: So you're more likely to act impulsively and use social media compulsively instead of, like, checking yourself. 
 
 Anderson Cooper: You want to keep on it to keep getting-- 
 
 Dr. Kara Bagot: The good feelings. 
 
 2017: What is "Brain Hacking"? Tech insiders on why you should care 
 
 Teenagers now spend on average four and a half hours a day on their phones. All that time has resulted in a fundamental shift in how a generation of american kids acts and thinks. 
 
 Jean Twenge: When smartphones went from being something only a few people had to something that the majority of people had, it had this really big effect on how teens related to each other. 
 
 "it should be a tool that you use. Not a tool that uses you." 
 
 Jean Twenge is a psychology professor at San Diego State University. She spent five years combing through four large, national surveys of 11 million young people since the 1960's. She discovered sudden changes in the behavior and mental health of teens born in 1995 and later, a generation that she calls "I-gen". 
 
 Jean Twenge: They're the first generation to spend their entire adolescence with smartphones so a lot of them can't remember a time before smartphones existed. 
 
 Anderson Cooper: There have been generational shifts before in the past, haven't there? 
 
 Jean Twenge: Certainly. But this one's much more sudden and pronounced than most of the others. 
 
 The iPhone was introduced in 2007. Smartphones gained widespread usage among young people by 2012. Jean Twenge says she was startled to find that in the four years that followed, the percentage of teens who reported drinking or having sex fell. But the percentage who said they were lonely or depressed spiked. It's possible other factors may have played a role, but Twenge says she wasn't able to identify any that correlated as closely as the growing popularity of the smartphone and social media. 
 
 Jean Twenge: It's not just the loneliness and depression from these surveys. It's also that ER visits for self harm like cutting have tripled among girls age 10 to 14. 
 
 Anderson Cooper: What are teens doing on their phones that could be connected to depression? 
 
 Jean Twenge: It could be anything. There's kind of two different schools of thought on this. That it's the specific things that teens are doing on their phones that's the problem. Or it could be just the sheer amount of time that they're spending on their phones that is the problem. 
 
 Correspondent Anderson Cooper with Jean Twenge 
 
 Finding definitive answers about social media's influence on mental health can be a frustrating exercise. Eighty-one percent of teens in a new national survey by the Pew Research Center said they feel more connected to their friends and associated social media use with feeling included. But in a month-long experiment at the University of Pennsylvania, college students who limited themselves to just 30 minutes a day on Facebook, Instagram and Snapchat reported significant decreases in loneliness and depression. 
 
 Jean Twenge: A lot of times with these technological shifts is these things are adopted because they're so wonderful and convenient. And we don't realize until later the possible consequences. And I think fortunately in the last year or so there's been more discussion about how can we manage the use of our devices. 
 
 Facebook and Instagram have introduced settings to allow users to monitor app use. And Apple, the company that started the smartphone revolution, has built a new feature for parents to set time restrictions on apps. 
 
 Anderson Cooper: Tech companies say there are tools out there that they have supplied and that they're doing their part. 
 
 Jean Twenge: A lot of parents, probably the majority I talk to, don't even realize those tools are available. and I wish they happened five years ago instead of now. But better late than never. 
 
 For its part, the National Institutes of Health has just finished enrolling the 11,000 kids for its landmark brain study. Early next year, the data will be made available to any researcher around the world investigating the effect of a device that's become the most dominant technological presence in young lives. 
 
 Jean Twenge: Smartphones are great things, They are a wonderful piece of technology. They allow us to find our way around and look up the weather and do all that kind of stuff. And if you do it for a half an hour or an hour a day, fine. No problem. Then you're using it for what it's good for. But you have to use it for what it's good for and then put it down. I mean, it should be a tool that you use. Not a tool that uses you. 
 
 Produced by Guy Campanile and Andrew Bast. Associate producer, Lucy Hatcher ||||| Young people who spend more than seven hours a day staring at a screen have different brain structures compared to the average child, according to a landmark US study. 
 
 The research, funded by the National Institute of Health and led by the University of California, San Diego, found children who spend more time online have premature thinning of the cortex, the brain's outermost layer that processes sensory information. 
 
 “We don't know yet if it's a bad thing. It won't be until we follow them over time that we will see if there are outcomes that are associated with the differences that we're seeing in this single snapshot,” researcher Dr Gaya Dowling told 60 Minutes. 
 
 Scientists are still not clear... ||||| ABCD study completes enrollment, announces opportunities for scientific engagement 
 
 Richard Watts, PhD, University of Vermont and Fair Neuroimaging Lab, Oregon Health and Science University 
 
 The National Institutes of Health announced today that enrollment for the Adolescent Brain Cognitive Development (ABCD) Study is now complete and, in early 2019, scientists will have access to baseline data from all ABCD Study participants. 
 
 There are 11,874 youth, ages 9-10, participating in the study, including 2,100 young people who are twins or triplets. All will be followed through young adulthood. 
 
 The ABCD Study is a landmark study on brain development and child health that will increase understanding of environmental, social, genetic, and other biological factors that affect brain and cognitive development and can enhance or disrupt a young person’s life trajectory. Coordinated by the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism, the study is supported by eight other NIH institutes and offices, as well as the Centers for Disease Control and Prevention and other federal partners. 
 
 The study—being conducted at 21 research sites around the country—will use advanced neuroimaging to observe brain development in children throughout adolescence, while tracking social, behavioral, physical and environmental factors that may affect brain development and other health outcomes. 
 
 Anonymized study data are being made available to the broad research community on a regular basis. This will allow scientists to analyze data and ask novel questions that were not even anticipated in the original study planning. Offering these data while the study is in progress means that both ABCD investigators and non-ABCD researchers will have access to the datasets to pursue their own research interests. 
 
 Medical University of South Carolina 
 
 There are many health topics that are of interest to researchers, policy makers, educators, parents, and the participants themselves, which scientists can now study using the baseline assessment data. These data can then be tracked over time and used to make predictions as youth develop and are shaped by their life experiences. Scientists can look at brain characteristics associated with impulsive action or early psychopathology; the impact of health behaviors (e.g., sleep, physical activity) on cognitive and brain development; or traits associated with media use, including screen time exposure. For example, a recent study by ABCD investigators showed associations between differing amounts and kinds of screen time (e.g., video games vs. social media) and different structural brain characteristics, psychological traits, and cognitive function. Scientists will be able to follow participants over time to understand how media use will influence a person’s development, underscoring the unique opportunity provided by the ABCD study. 
 
 Similarly, researchers can look at risk and resilience factors for mental illness and substance use, including genetics, family history, traits such as impulsivity, and exposure to positive and negative environmental events. With longitudinal data, the developmental trajectories of the participants can be tracked to better understand these complex relationships, and eventually to improve prevention or mitigate risks for adverse outcomes. 
 
 Additional data from the first 4,500 children enrolled in the study will be released this month, and data from the full participant cohort (11,874) will be available in early 2019. In addition, scientists will be able access a new tool through the NIMH Data Archive — the Data Exploration and Analysis Portal (DEAP). DEAP will facilitate analysis of the ABCD data, allowing users to analyze the data online without downloading it, while providing appropriate statistical models and tools that take advantage of the ABCD Study design. DEAP will enhance the ability of researchers to address myriad questions related to adolescent development. 
 
 Researchers interested in accessing these data can visit the NIMH Data Archive. As findings are published in various journals by both ABCD investigators and other scientists, study coordinators will continue to post information on the study website at https://abcdstudy.org/scientists-publications.html. 
 
 The ABCD study is supported by the National Institute on Drug Abuse (NIDA), the National Institute on Alcohol Abuse and Alcoholism (NIAAA), the National Cancer Institute, the Eunice Kennedy Shriver National Institute of Child Health and Human Development, the National Institute of Mental Health, the National Institute on Minority Health and Health Disparities, the National Heart, Lung and Blood Institute, the National Institute of Neurological Disorders and Stroke, the NIH Office of Behavioral and Social Sciences Research, the NIH Office of Research on Women’s Health, and the Division of Adolescent and School Health at the Centers for Disease Control and Prevention (CDC), with additional partnerships with the National Institute of Justice, the CDC Division of Violence Prevention, the National Science Foundation, and the National Endowment for the Arts. For information on all study sites, go to https://abcdstudy.org/sites/abcd-sites.html. 
 
 Learn more about NIDA by following #ThisIsNIH on Twitter, Facebook, and Instagram when we take over NIH’s social media platforms from December 10-15. On Thursday, December 13, at 11am ET, join us on the NIH Facebook page for a live panel and Q&A with NIDA’s Director Dr. Nora Volkow about vaping. 
 
 For more information, contact the NIDA press office at media@nida.nih.gov or 301-443-6245. Follow NIDA on Twitter and Facebook. 
 
 About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov. 
 
 NIH…Turning Discovery Into Health®
– Sunday night's 60 Minutes report on screen time and kids has parents buzzing: "Heavy screen time appears to impact children's brains," reads a sample headline making the rounds. The report looked at the National Institutes of Health's Adolescent Brain Cognitive Development (ABCD) study, in which more than 11,000 9- and 10-year-olds will be followed for a decade "to see how childhood experiences impact the brain," per Bloomberg. The study began in 2013. 60 Minutes reported on the "first wave of information" from the study, which involved brain scans of 4,500 children, per AFP. Some key findings: children who spend more than seven hours per day on screens may experience premature thinning of the cortex, the outermost layer of the brain that processes sensory information, and kids who spend more than two hours per day on screens score lower on thinking and language tests. But the Telegraph notes that the second finding came from an observational study, meaning it wasn't possible to prove a link between the extra screen hours and the lower cognitive skill scores, and as for the premature cortical thinning (a natural process that typically happens in later development), "we don't know if it's being caused by the screen time," a researcher explains. "We don't know yet if it's a bad thing." Axios notes that these are preliminary results that have not been published in a peer-reviewed journal, and at the New York Times, science reporter and author Benedict Carey notes that the early results from the NIH study are actually a "mixed bag." Researchers, he says, have yet to find hard evidence of screen time causing "meaningful" changes to the adolescent brain. For 60 Minutes' full report, including outside experts talking about screen time, see here. (Here's one thing you may not have to worry about when it comes to screens.)