Victoria L. Dunckley, MD

Reset Your Child's Brain


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as is healthy. Studies also show that screen exposure delays the onset of sleep, suppresses REM sleep (which we need to “clean house” and solidify learning), and prevents the body temperature from dropping to levels supportive of deep sleep.23

      Without restorative sleep, the brain does not function properly. Muscles become tense, and you feel tired the next day — even if the total sleep time was adequate. To compensate, the body releases more stress hormones to keep you awake, perpetuating a vicious cycle. Even short exposures to electronic screens (such as fifteen minutes) near bedtime can produce these changes. While a screen’s blue tones are much more potent in terms of melatonin suppression, it’s been shown that red light and dimmer displays during evening hours are still quite disruptive.24 Interestingly, a study showed electromagnetic radiation from cell phone towers produced a similar degree of suppression in melatonin,25 suggesting that exposure to a screen device plus EMFs may deliver a “double whammy” of sleep disturbance.

      Light-at-Night: Effects on Sleep, Mood, and Cognition

      In general, non-restorative sleep is associated with poor memory, irritability, and impaired school or work performance.26 A 2010 sleep study conducted at the JFK Medical Center showed that over half of the children who used electronic media at night not only suffered sleep problems but mood and cognitive problems during daytime.27 Other studies have linked light-at-night from electronics to depression and suicidally,28 and some speculate that disrupted circadian rhythms lead to low serotonin levels — the brain chemical of well-being.29

      There is no “safe dose” of after-lights-out texting that does not cause sleep disturbance and daytime sleepiness.30 Teens are notorious for texting at night; some even sleep with their phones. Unfortunately, both children and teens also use the computer in the late afternoons and evenings for schoolwork, making screen-related sleep disturbance a ubiquitous problem.

      Reward and Addiction Pathways

      There is much discussion today about whether intense video game play or Internet use can be considered an addiction. The relationship between interactive screen-time, addiction, and stress is complex, but a number of key studies shed light on the issue. There is actually an abundance of evidence supporting the concept of screen or tech addiction, but perhaps most convincing are imaging studies. Brain scan research indicates that when heavy gamers — or even individuals who merely crave gaming — are shown computer game cues, their brains “light up” in exactly the same areas as the brain of someone addicted to drugs.31 One study showed that in college students who reported cravings for online gaming, just six weeks of heavy Internet video game playing produced changes in those students’ prefrontal cortex (part of the frontal lobe, the brain’s executive center) similar to those seen in the early stages of addiction.32 Internet and video game addiction studies in adolescent and young adults have found strong physical evidence that brain damage occurs with heavy use.33 Other brain-scan studies have demonstrated that playing video games releases large amounts of dopamine,34 the primary brain chemical associated with reward pathways activated in addiction.

      How is all this occurring when there is no toxic “substance”? Compulsive video game and Internet use can be considered an arousal addiction — that is, the user becomes addicted to high levels of stimulation and arousal and then needs more stimulation to achieve or sustain that feeling. Tolerance occurs because reward pathways — the exact same reward pathways in the brain that are involved in chemical addictions — become overactivated. In other words, the pathways become desensitized from overuse. Meanwhile, in addition to the “rush” of stress hormones released during use, the screen-addicted person experiences stress reactions at other times: when he or she is not able to play; when craving or negotiating for play; when experiencing physical or psychological withdrawal from play; and when play is cut short. Thus, the stress reactions related to the addiction process compound the stress of screen-time itself.

      While true screen addiction is less common than ESS, it is possible that ESS may set the stage for tech and other addictions in children and adolescents. The cycle of craving play, playing, and then withdrawing not only creates stress but also causes the brain to be more sensitive to stress, resulting in a “hair-trigger response” to even mild stressors — a pattern known to develop in individuals with substance abuse.35 The inability to deal with stress leads to the need to escape, and the user uses more. In fact, “escapism” — using screen-time to avoid reality — has been found to be a predictor of video game addiction.36 Thus, repeated arousal and activation of reward pathways induced by electronics’ use may “prime” the brain not just for tech addiction but for other addictions as well.37

      Vividness, Screen Size, and Pace

      Whatever the subject matter, the style or manner in which content is delivered has its own impact. Research indicates that movement, zooms, pans, cuts, and vividness (how “lifelike” images are) all trigger the orienting response and contribute to repeated fight-or-flight reactions.38 Screen size affects arousal levels as well, with larger screens producing higher levels of arousal. It’s worth noting that in today’s market, whether the device is a handheld device, laptop, desktop monitor, or television set, the trend is “the bigger the better.”39 Regarding Internet activity, the speed and frequency of downloading and use of video all contribute to alertness and arousal, in addition to that contributed by the actual content.40 As technology improves, so does its ability to engage and arouse.41

      Media Multitasking

      Multitasking could be more accurately called “task switching.” Juggling more than one task at a time places increased cognitive demands on the brain, which increases arousal levels and stress. (And just because your child may be considered “good at it” does not mean multitasking is good for him or her!) Kids now chat while playing online games, Skype and text while doing homework, and email and surf the web on a smartphone while watching TV. Studies show that high multitasking is associated with physiological stress, impaired cognition, and negative mood due to frequent attentional switching, the experience and inefficiency of being frequently interrupted, and sensory overload.42

      Radiation from Electromagnetic Fields (EMFs)

      EMFs represent another possible source of hyperarousal and other stress reactions, at least for some people. Like other aspects of electronics, EMFs may induce stress directly, or immediately upon exposure, and indirectly, by affecting sleep quality. Several studies have demonstrated immediate effects on particular stress markers, and other research suggests sleep patterns and biorhythms may be affected. Stress reactions have been found to occur at the level of the cell as well. See the EMF appendix for a more detailed discussion of this research.

      Chronic Stress, Hyperarousal, and Your Child

      Chronic stress and hyperarousal generally lead to some form of dysregulation — the loss of the ability to modulate responses in a manner appropriate to the current environment. This can occur in anyone no matter what the source of stress, and as we’ve seen, it occurs in children from screen-time, leading to ESS.

      As I describe in the introduction, working closely with children who’d experienced serious trauma from abuse and neglect helped me recognize that screen-time could induce symptoms that mimicked those seen in children who were perpetually in “survival mode.” In this section, I look more closely at how chronic stress and hyperarousal affect children in terms of physiology and behavior, using Aiden’s story to illustrate certain points. Because ESS is essentially a stress syndrome, examining how stress manifests in children can illuminate why ESS causes so many problems so easily. Figure 3 outlines the myriad of biological, psychological, and social dysfunctions produced by stress; all of these impacts are likewise seen with Electronic Screen Syndrome.

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