Читать книгу Reset Your Child's Brain - Victoria L. Dunckley MD - Страница 11
ОглавлениеALL REVVED UP AND NOWHERE TO GO
How Electronic Screen Media Affects Your Child’s Brain and Body
It is not stress that kills us, it is our reaction to it.
— Hans Selye
On the eve of his big sister Liz’s high school graduation, nine-year-old Aiden sits with his parents and relatives at a celebration dinner, bored by their “adult” conversation and irritated at all the attention showered upon Liz.* He can’t wait to get back to his video game! Before dinner, Mom had (annoyingly) called him away to join the family, and then she got mad when he spent a few minutes getting to the next level and saving his game. So many people in the house make him restless; he squirms uncomfortably and drums his fingers on the table, waiting to be excused.
Finally, he is allowed to escape the dinner table, and he settles into a corner of the living room couch to play his Nintendo DS. For the next hour or so, he is completely oblivious to the company in the house. Although he’s already played much longer than his mother likes, she lets him continue, knowing these family situations are a little overwhelming for him. And besides, the game keeps him occupied. What’s the harm? she thinks. It’s just for today.
However, in the meantime, a perfect storm is brewing. As the play continues, Aiden’s brain and psyche become overstimulated and excited — on fire! His nervous system shifts into high gear and settles there while he attempts to master different situations, strategizing, surviving, accumulating weapons, and defending his turf. His heart rate increases from 80 to nearly 100 beats per minute, and his blood pressure rises from a normal 90/60 to 140/90 — he’s ready to do battle, except that he’s just sitting on the couch, not moving much more than his eyes and thumbs. The DS screen virtually locks his eyes into position and sends signal after signal: “It’s bright daylight out, nowhere near time for bed!” Levels of the feel-good chemical dopamine rise in his brain, sustaining his interest, keeping him focused on the task at hand, and elevating his mood. The intense visual stimulation and activity flood his brain, which adapts to the heightened level of stimulation by shutting off other parts it considers nonessential.
The visual-motor areas of his brain light up. Blood flows away from his gut, kidneys, liver, and bladder and toward his limbs and heart — he’s ready to fight or escape! The reward pathways in his brain also light up and are reinforced by the flood of dopamine. He is so absorbed in the game, he doesn’t notice when his little sister, Arianna, comes over until she puts her chubby hand on the screen, trying to get his attention.
“DooOOON’T!!” he shouts and roughly shoves her out of the way. Arianna falls backward, bursts into tears, and runs to their mother, who silently curses herself for letting Aiden play this long.
“All right, that’s it. Time to start getting ready for bed. Get your pajamas on and you can have a snack before you go to bed,” she says, pulling the DS out of Aiden’s hands and turning it off in one fell swoop.
Aiden looks at his mother with rage. How dare she ruin his game because of his stupid sister!
“Fine!” he shouts, runs up the stairs, and slams his bedroom door. His primitive brain is fully engaged now, turning him into an enraged animal ready to fight off all challengers. He rips all the sheets off his bed and then throws his lamp on the floor, providing a satisfactory crash and shatter. Thinking about how wronged he’s been and filled with visions of revenge, he kicks the wall a few times and then pounds on his bedroom door, putting a big hole in it.
Downstairs, his relatives sit in quiet shock and murmur to each other how they’ve never seen him act like this. Dad runs up the stairs to contain his son. Calmly, his dad holds him in a bear hug from behind, waiting for the rage to subside.
As the dopamine in his brain and the adrenaline in his body begin to ebb, his rage loses its focus. Now, the pent-up energy takes on a disorganized, amorphous form. Aiden feels like he can’t think straight or get himself together. While he spaces out, his dad helps him put his pajamas on and they go back downstairs. Stress hormones remain high, however, making it difficult for him to relax or think clearly. He seems a little confused, actually. His relatives look at him with a mixture of concern and love, but they also wonder why his parents let him “get away with” this kind of behavior. His mother intuitively knows that direct eye contact will overstimulate him again, so she approaches him slowly from the side, and rubs his back gently.
When his favorite aunt looks him in the face sympathetically, he immediately distrusts her intentions. Eye-to-eye interaction is interpreted by his primitive-mode brain as a challenge, and he starts getting revved up again. His mother intervenes, and takes him up to his room. She lowers the light, settles him into bed, and starts to read him a soothing story. His nervous system attempts to regulate itself back to normal, but it seems to still be held hostage by his hyped-up emotions. That night, after he does finally fall to sleep, Aiden awakens repeatedly with panic attacks — his heart races and blood pounds in his ears. He’s scared of the dark, and worried that his angry outburst has upset and alienated his parents. His mother, meanwhile, confiscates the DS and decides to take it with her to work on Monday. (She really wants to throw it in the trash, but it was expensive!)
The following morning, the fight in Aiden has subsided, but the aftermath leaves him in a fog, listless, weepy, and exhausted. He experiences an increased craving for sweets while cortisol, the stress hormone, drives his blood sugar up and down erratically. It will take weeks before his body, brain, and mind return to some sense of balance.
Meanwhile, his mother reaffirms her commitment “to get rid of those damn video games.”
Perceived Threat and the Fight-or-Flight Response
Does Aiden’s story sound familiar? Why would a seemingly normal, loving child become so enraged and difficult after playing video games? Though his response may seem extreme, there’s actually a completely natural explanation for Aiden’s behavior.
Playing video games mimics the kinds of sensory assaults humans are programmed to associate with danger. When the brain senses danger, primitive survival mechanisms swiftly kick in to provide protection from harm. This response is instantaneous; it is hardwired in our genes and necessary for survival. Keep in mind that the threat does not have to be real — it only needs to be a perceived danger for the brain and body to react. Think of how you feel when watching a truly scary movie. Your heart rate increases, your stomach twists into knots, and your limbs tense, poised to react. Even though you know “it’s only a movie,” the graphic and threatening images produce an intense, undeniable physiological response. When this instinct gets triggered, our nervous system and hormones influence our state of arousal, jumping instantly to a state of hyperarousal — the fight-or-flight response. These feelings can be hard to shake off even after the movie is over, which is why even adults sometimes have nightmares afterward — usually of being attacked (fight) or of trying to run away from danger (flight).
While in medical school, we often heard this state referred to as “running from the tiger,” since during ancient times humans protected themselves from predators by literally fighting or fleeing. Today, we still need this rapid stress response for emergency situations, and on a day-to-day basis mild stress reactions help us get things done. But for the most part, repeatedly enduring fight-or-flight responses when survival is not an issue does more harm than good. When the fight-or-flight state occurs too often, or too intensely, the brain and body have trouble regulating themselves back to a calm state, leading to an experience of chronic stress. Chronic stress is also produced when there is a “mismatch” between fight-or-flight reactions and energy expenditure, as occurs with screen-time; the physical energy needs to be discharged for the system to re-regulate. Once chronic stress sets in, brain function suffers. With children, whose nervous systems are still developing, this sequence of events occurs much faster than it does for adults, and the chronically stressed child soon starts to struggle. If your child is experiencing behavior issues, falling grades, mood swings, problems socializing, or other chronic difficulties, it is fairly safe to assume that his or her nervous system is being subjected to stress on a repeated basis.
As parents (and as clinicians), when we see children who are revved up all the time, we instinctively do all we can to make them feel safe and calm. We don’t show them scary movies, take them bungee jumping, or let them hang out with rougher children. But in today’s environment, our children are under nearly constant assault from electronic screen devices, and they react in the same way as they might to any other danger, resulting eventually in distressing symptoms and dysfunction — Electronic Screen Syndrome. When a child is experiencing ESS, it only makes sense to use the same strategy we use in other stressful situations: minimize stress where you can — electronic or otherwise — and minimize overstimulation. Whether or not other stressors are present, electronic screen media heightens stress states, and therefore all mental, neurological, and physical symptoms worsen in tandem. Conversely, many times when electronic stress is removed, other stressors become more manageable or are no longer experienced as stressors. Figure 1 depicts the cycle of stress and dysfunction, compounded by additional stress from interactive screen-time.
Figure 1. Electronic screen stress and stress reactions influence each other in a vicious cycle
Sensitive and Vulnerable: Eyes, Brain, and Body
Exactly how do electronic screen devices cause stress? To understand what factors may be affecting your child’s nervous system, we need to take a closer look at the workings of the brain when confronted with the many electronic stimuli present in today’s environment. Although in Aiden’s case it was video game play that disrupted his behavior, it’s essential to realize that any electronic screen interaction, regardless of content, can irritate the nervous system — “it’s the medium, not the message.” Why? Because the interface between the screen and your child’s nervous system allows natural processes to be disturbed. The three main points of access for development of ESS are your child’s eyes, brain, and body, including the body’s natural energy fields. Understanding the various pathways by which electronic screens affect your child helps you appreciate why any kind of interactive screen-time can wreak havoc.
The Eyes
The eyes provide a particularly potent route for electronic screen toxicity, regardless of content being processed. How does this communication between unnatural screen stimulation and the brain occur? The eyes are directly connected to the central nervous system, which allows the physical environment to have a powerful influence on brain activity. In fact, the eyes are the only part of the central nervous system exposed to the outside world. Directly behind each eye are the retina and the optic nerve, which receive information from the environment in the form of light. The optic nerves extend back from each eye and then cross at the base of the brain, where they communicate with the small but vital pineal gland, whose main job is to help regulate the sleep-wake cycles by secreting a sleep hormone (melatonin) that’s triggered by darkness.
There are at least three eye-related “routes” that can be accessed. First, because electronic screens emit unnaturally bright light, they convey information to the brain that’s inconsistent with what’s occurring in the real world, desynchronizing the body clock and other biological rhythms.1 Second, interacting with a 2D screen alters normal eye muscle movements, including those used for changes in depth. This influences visual and vestibular (relating to sense of balance and body position) development, cognition, and mood regulation. Third, electronic media provides intense, unnatural, “arresting” visual stimulation that affects sensory and attention processes.2 This is true no matter what the specific content is. Thus, screen devices affect your child through his or her eyes by light, muscle movement signals, and visual stimulation.
The eye itself may suffer as well. Aside from eye strain or “computer vision syndrome,” which causes blurred vision, headaches, and dry, irritated eyes,3 the LED light emitted from screens has been implicated in retinal damage in various laboratory and animal studies.4 Both blue light and intense light have been implicated. Screen-time has also been linked incrementally to a narrowing of retinal blood vessels — a marker for cardiovascular disease.5
The Brain
The second point of access for screen activities is the brain itself. The brain is evolutionarily designed to respond to stimulating visual input — brightness, color, contrast, and movement — called the orienting response. Back in the day when we had to hunt, gather, or fish for our food, this kind of sensory input suggested the presence of prey or predators, and a rapid response to such input increased our odds of survival. In other words, the orienting response helps us assess a threat before we determine whether to fight or flee. When these stimuli are artificially created, however, the brain’s orienting response gets hijacked, creating chemical, electrical, and mechanical shifts that raise arousal levels. When this happens repeatedly, the brain remains on heightened alert.
Screen devices access the brain on a psychological level as well; video games, for example, are purposely designed to exploit psychological needs and thus activate natural reward pathways, releasing feel-good chemicals in the brain. The brain is attracted to interactive screen-time for other psychological reasons, too, including our need for immediate gratification and responsiveness, aspects that gaming, social media, Internet use, and even texting can provide.
The Body
In addition to effects of electronic screens on the eyes and the brain are the effects on your child’s body. With electronic screen interaction, blood flows away from organs like the gut and reproductive organs and toward the limbs and heart. Heart rate and blood pressure increase and stress hormones are released, preparing the body for fight-or-flight. This reaction might not be surprising when one considers how a child playing an action-oriented video game might respond, but in fact research tells us that all forms of screen-time create subtle changes in the cardiovascular system that can cause damage over time.6 In addition, sitting for lengthy periods of time can cause unhealthy bodily changes within as little as thirty minutes, and the majority of screen-time is spent in a sedentary fashion.
The fact that screen-time is associated with metabolic syndrome is telling. Metabolic syndrome is a combination of high blood pressure, midsection weight gain (“spare tire”), abnormal cholesterol levels, and high fasting blood sugar. It’s a serious condition that can lead to diabetes, heart disease, and stroke. Up until recently, it was rarely seen in children; now it’s become common. It’s unclear why it develops in some but not others, but it’s thought to be related to chronic stress and poor sleep. Even more telling is the fact that the link between metabolic syndrome and screen-time holds true regardless of activity level — a finding that suggests that screen-time produces unhealthy physiological changes that are above and beyond changes seen in those with low activity levels.7
The Biofield
The matrix of biological electromagnetic fields present in the human body represents yet another potential interface between electronics and your child, but this will be discussed in more detail in appendix B on EMFs.
All Revved Up: Fight-or-Flight Mechanisms Related to Screen-Time
Thus, through the eyes, brain, and body, use of electronic screen media sends unnatural and overstimulating messages to the nervous system. Via these pathways, numerous mechanisms promote and maintain the fight-or-flight response, leading to the chronic hyperarousal associated with ESS. It doesn’t take much screen-time exposure for some children to get all revved up because so many mechanisms can occur at once and then feed off one another. Each of these mechanisms is capable of self-perpetuating the stress cycle, while simultaneously lowering a child’s resistance to future stress. Figure 2 depicts the array of screen-related factors that can elicit fight-or-flight reactions. Let’s look at each of these factors in turn.
Figure 2. Screen-related factors contributing to hyperarousal or fight-or-flight
Intense Sensory Stimulation
Screen brightness, quick movements, and supersaturated colors all contribute to visual sensory overload.8 Intense stimulation heightens attention and arousal, feeding into fight-or-flight.9 Furthermore, excessive stimulation can overwhelm the sensory system, causing other parts of the brain to shut down in order to compensate. Afterward, the brain experiences a relative sensory deprivation, which can feel uncomfortable and lead to irritability. Some individuals may even suffer light- or screen-associated seizures, tics, and migraines when intense visual stimulation produces electrical excitability, or the overfiring of brain networks.10 In Japan in 1997, over seven hundred people, mainly children, experienced seizures and vomiting after watching a particular Pokémon cartoon episode that utilized flashing colored lights in a scene depicting two characters in battle.11 The vast majority of victims had never had a seizure before. While extreme, this example shows how intimate the relationship is between the eyes and the brain. We should view the visual effects from electronic screen interaction as a spectrum, with seizures, tics, and migraines representing the more severe or tangible manifestations on one end, and everyday “irritation” and general nervous system dysfunction on the other.
Another sensory-related reaction to extended screen-time is the game transfer phenomenon, where users experience visual hallucinations of game-related objects, like an imprint, after prolonged play.12 Lastly, from a development perspective, repeated exposure to intense sensory stimuli leads to an overactive visual system; the child will attempt to pay attention to everything around him or her, making it difficult to focus and causing other sensory integration issues.13
Psychologically Engaging Content or Activity
Though not all screen activities are games, those that are add another layer to the fight-or-flight story. As the need to win or improve is repeatedly reinforced in some way during play (by earning rewards, escaping from threats, being promoted to the next level, and so on), the player becomes more and more hyperaroused. Meanwhile, the feel-good brain chemical dopamine is continually being released, causing the player to want to continue playing — often for longer than planned. The more engaging a game is, the more it increases dopamine-related attention and arousal, which reinforces itself over time and makes it harder to stop playing. Game designers are absolute geniuses at creating the timing and intensity of in-game rewards.14
In terms of content — for both video game and Internet use — violent, competitive, sexual, vivid, interesting, challenging, and bizarre images and situations all increase arousal or fight-or-flight reactions.15 In terms of game type, role-playing games, such as multimember online role-playing games (MMORPGs), are known to be particularly addicting.16 In part, they may be compelling because they play off of adolescent developmental needs, such as identity formation.17 With younger children, the game Minecraft, which consists of building structures, items, and weapons out of various materials in the form of blocks — activities that seem relatively benign on the surface — is frequently described as “mesmerizing” by parents as their children become “obsessed” with it.18
Disruption of the Body Clock
Both natural and artificial light relay information to the brain and impact the body’s biorhythms, including the sleep-wake cycle, a “circadian rhythm,” and hormone cycles, which have daily, monthly, and seasonal variations.19 As mentioned, when the brain is exposed to the unnaturally bright light of electronic screens, the sleep signal hormone melatonin is suppressed, and natural biorhythms are disrupted.20 Additionally, light from screens tends to be rich in blue tones, which is particularly disruptive because blue light mimics daylight. Low melatonin is linked to depression and inflammatory states — such as cancer and autism — as well as alterations in hormone function, including reproductive hormones.21 Aside from melatonin suppression, light-at-night is associated with other hormonal abnormalities, such as low growth hormone.22 These changes in biorhythms and melatonin production result in poor sleep quality because the body does not enter the deeper phases of the sleep cycle as often or as long 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.
Figure 3. Effects of chronic stress and hyperarousal*
Blood Flow Shifts
This mechanism has potential long-term implications for brain development. When under stress, blood flow in the brain is repeatedly shunted away from areas of higher thinking (the cortex, or “new” brain, at the outermost layer) and toward more primitive areas (the limbic, or “old” brain, seated deep within). In other words, blood is directed to the areas involved in survival. Similarly, when addiction of any kind occurs during adolescence, it tends to stunt development of the brain’s frontal lobe, which is responsible for decision making, organization, attention, impulse control, task completion, and emotional regulation (to name a few!). If interactive screen-time induces a stress response and activates reward and addiction pathways, might it affect brain development by decreasing blood flow to the cortex and frontal lobe? Indeed, it very well might. Interestingly, when I’ve treated patients with the Reset Program and they continue to be screen-free afterward, they seem to mature developmentally in leaps and bounds — in a matter of months. This suggests that liberation from screens redirects robust blood flow back to the frontal lobe, thereby supporting healthy brain development.
Elevated Cortisol
Research suggests electronic screen activity is associated with altered cortisol regulation.43 While adrenaline is the dominant hormone released in an acute stress reaction, the hormone typically associated with chronic stress is cortisol. Cortisol actually serves to protect the body from stress reactions, but high cortisol levels over time cause harm. In fact, chronically high cortisol is correlated with obesity, high blood pressure, diabetes, metabolic syndrome, and hormone imbalance.44 During times of stress, when the body needs ready access to fuel, cortisol “loosens the reins” of blood sugar control by counteracting insulin. In the short term, this translates into unstable blood sugar levels, but in the long term it can lead to weight gain concentrated in the abdominal area and problems with insulin regulation. Recall how Aiden craves sweets after his episode; children under stress often crave sweets or other carbohydrates because of blood sugar fluctuations. As mentioned, research shows screen-time is a risk factor for metabolic syndrome regardless of activity level, and it is likely that high cortisol is one of the reasons why.
Additionally, elevated cortisol throws off the production of other hormones, such as thyroid and reproductive hormones, and over time excess cortisol damages the brain.45 Chronically elevated cortisol wreaks havoc on the nervous, cardiovascular, metabolic, and hormonal systems.
Oxidative Stress
Chronic stress — electronic or otherwise — puts stress on the very system that fights stress! At a molecular level, all cellular reactions in the body produce free radicals, which are unstable, unpaired electrons that must quickly grab another electron in order to stabilize. When a cell is healthy, free radicals are “scavenged” by adequate amounts of antioxidants — which are both ingested as nutrients and produced by the cell itself — and balance is maintained. But when the cell’s defenses are overwhelmed by too many stressors, antioxidants become depleted, and oxidative stress (excessive free radicals) ensues. As free radicals build unchecked, the unstable molecules containing them are forced to “grab” electrons from our own tissue. Nearby fats, proteins, and DNA are typically the elements vulnerable to being attacked. Eventually, this process creates inflammation, tissue damage, and inefficiency, further compromising the cell’s ability to contend with acute and ongoing stress.
Unfortunately, the brain is highly susceptible to oxidative stress for several reasons. First, oxidative stress can cause disruption of the blood-brain barrier, making it more vulnerable to toxins it should be protected from. Second, it’s also relatively hard to get antioxidant nutrients into the brain that could potentially provide the brain protection, so there’s never much of a buffer. And third, oxidative stress tends to attack the fatty sheaths that insulate brain cells, which can cause aberrant firing of networks. Meanwhile, a developing brain — because it is highly dynamic with increased energy needs — is more vulnerable to oxidative stress than a fully formed adult brain. This means that a child’s brain — especially if it is already compromised by a mental disorder — will develop damage from oxidative stress relatively quickly. The eyes are also vulnerable to oxidative stress; the retinal damage studies mentioned above also found markers associated with oxidative stress.46
Disturbed Sleep
The far-reaching effects of poor quality sleep have already been mentioned, and they can occur in children after just one night of not getting enough rest. Poor sleep goes hand in hand with both acute and chronic stress. In Aiden’s case, video game playing (and subsequent fight-or-flight rage) results in non-restorative sleep, which doesn’t allow his brain adequate recovery. After a night of poor sleep, the body produces adrenaline to get through the day, which can then cause difficulty falling or staying asleep the following night. Non-restorative sleep compounds hyperarousal and leaves a child feeling “wired and tired.”
Sleep hygiene is a set of practices sleep experts recommend to obtain quality rest on a daily basis. Recommendations include low levels of stimulation in the evening, exercise and exposure to lots of natural light during the day, banning electronics from the bedroom, and sticking to a regular sleep-wake schedule. Children and teens who are stressed tend to have poor sleep hygiene if left to their own devices.
Cognitive Dysfunction
If you’ve ever described your child as seemingly “out of it,” you may be witnessing the cognitive dysfunction that occurs when the brain has just been exposed to something it considers stressful. When Aiden tries to get ready for bed after his episode, he can’t quite get himself together and has trouble following sequential steps. After a poor night’s sleep, he continues to struggle with focus, long after the game has been turned off. Stress affects the ability to assimilate new facts, retain new information, and execute tasks. Short-term memory suffers. Cognitive dysfunction then translates into forgetting to complete or turn in homework assignments, falling grades, and a tendency to lose things. Chronic or repeated stress causes even more alarming effects, including loss of neurons, or brain cells, particularly in the hippocampus — an area important for forming and storing memories.47
Poor Sense of Time
Both sense of time and time management can be affected by stress. If we were to ask Aiden in the moment how long he has been playing his game, in all likelihood he will underestimate the time spent — even if he is being honest and not trying to minimize in order to avoid getting into trouble. In fact, video gaming has been found to cause time distortion in players, nearly universally.48 Both video games and Internet use cause problems with managing time as well: being late, underestimating how much time a task will take, procrastinating, forgetting appointments and activities, and so on. Interestingly, children with extensive traumatic histories have great difficulty with time perception. They appear to be forever stuck in the moment, unable to look forward or backward — an advantage if you’re trying to survive. Focusing on the “here and now” serves self-preservation in extreme situations. But in everyday life, it translates into impulsive actions, repeating mistakes by failing to reflect on their consequences, and an inability to focus on future goals.
Impaired Social Interactions
The very essence of survival mode centers around defensiveness. While in this state, being open and intimate creates vulnerability and therefore poses a threat. During Aiden’s episode, direct eye contact with his aunt provokes him. This is a primitive reaction, and it is why we don’t stare unfamiliar dogs directly in the eye — they’ll see it as a challenge. Try making sustained eye contact with your child after video game play — he or she will likely become uncomfortable and look away.
Chronically hyperaroused children get defensive easily when playing games and are often “sore losers.” They may feel wronged when something happens by chance, and they may be more prone to cheating. These behaviors can happen online and in other settings, like the playground. As this defensiveness rises, the child’s relationships can become affected. Interestingly, while both children and adults claim that social media helps them feel connected to others, it appears that, in fact, time spent online actually increases depression and a sense of social isolation.49
Mood Dysregulation
Emotional (or mood) dysregulation is one of the end products of all these disturbed pathways and mechanisms, and it is nearly always present when a child is chronically hyperaroused. It occurs as the fight-or-flight response causes shifts in mechanical, chemical, and electrical systems (such as blood flow, brain chemistry and hormones, and overstimulated networks) and is compounded by poor sleep. Mood dysregulation is characterized by poor frustration tolerance, tearfulness, irritability, mood swings, and meltdowns or aggression. Aiden becomes extremely emotionally volatile immediately following video game play, and then he continues to feel irritable and anxious for days and weeks afterward. If you’ve ever felt like you “have to walk on eggshells” around your child, then it is likely you are all-too familiar with this phenomenon.
For a summary that pulls all the pathways, mechanisms, and potential consequences together, see the table in appendix A, “Table of Physiological Mechanisms and Effects of Interactive Screen-Time.” In fact, bookmark this page to remind yourself why your child’s brain needs a reset!
Chapter 2 Take-Home Points
• The brain does not discern between real or perceived threats, and artificially intense stimulation from electronic screen media produces a psychological and physiological fight-or-flight reaction, regardless of content.
• These reactions have both immediate and cumulative effects, which eventually cause damage.
• Screen devices interface with your child via the eyes, brain, and body, triggering changes in blood flow, brain chemistry, electrical excitability, and hormones.
• Since the eyes are a direct extension of the central nervous system, they provide a pathway for overstimulation of the sensory system as well as for unnaturally bright light to suppress melatonin (the sleep hormone) and desynchronize the body clock.
• Numerous mechanisms, including disturbed sleep, reward/addiction pathways, brain-blood flow shifts, intense sensory experiences, and engaging content precipitate and perpetuate an ongoing stress response.
• Electronics-related sleep disturbance, in and of itself, creates a vicious cycle of exhaustion, compromised mood and cognition, more stress because of dysfunction, more insomnia, and craving for more stimulation.
• Examining the known effects of chronic stress and hyperarousal can assist in envisioning how screen-time may affect your child’s behavior, mood, and social skills.
* This story is a dramatization based on true events.
* This graphic does not include all stress reactions, and some of these factors are interrelated.
