Information below by Victoria L. Dunckley, M.D., the author of Reset Your Child's Brain
- Screen time disrupts sleep and desynchronizes the body clock.
Because light from screen devices mimics daytime, it suppresses melatonin, a sleep signal released by darkness. Just minutes of screen stimulation can delay melatonin release by several hours and desynchronize the body clock. Once the body clock is disrupted, all sorts of other unhealthy reactions occur, such as hormone imbalance and brain inflammation. Plus, high arousal doesn’t permit deep sleep, and deep sleep is how we heal.
- Screen time desensitizes the brain’s reward system.
Many children are “hooked” on electronics, and in fact, gaming releases so much dopamine—the “feel-good” chemical—that on a brain scan it looks the same as cocaine use. But when reward pathways are overused, they become less sensitive, and more and more stimulation is needed to experience pleasure. Meanwhile, dopamine is also critical for focus and motivation, so needless to say, even small changes in dopamine sensitivity can wreak havoc on how well a child feels and functions.
- Screen time produces “light-at-night.”
Light-at-night from electronics has been linked to depression and even suicide risk in numerous studies. In fact, animal studies show that exposure to screen-based light before or during sleep causes depression, even when the animal isn’t looking at the screen. Sometimes parents are reluctant to restrict electronics use in a child’s bedroom because they worry the child will enter a state of despair—but in fact, removing light-at-night is protective.
- Screen time induces stress reactions.
Both acute stress (fight-or-flight) and chronic stress produce changes in brain chemistry and hormones that can increase irritability. Indeed, cortisol, the chronic stress hormone, seems to be both a cause and an effect of depression—creating a vicious cycle. Additionally, both hyperarousal and addiction pathways suppress the brain’s frontal lobe, the area where mood regulation actually takes place.
- Screen time overloads the sensory system, fractures attention, and depletes mental reserves.
Experts say that what’s often behind explosive and aggressive behavior is poor focus. When attention suffers, so does the ability to process one’s internal and external environment, so little demands become big ones. By depleting mental energy with high visual and cognitive input, screen time contributes to low reserves. One way to temporarily “boost” depleted reserves is to become angry, so meltdowns actually become a coping mechanism.
- Screen-time reduces physical activity levels and exposure to “green time.”
Research shows that time outdoors, especially interacting with nature, can restore attention, lower stress, and reduce aggression. Thus, time spent with electronics reduces exposure to natural mood enhancers.