It’s virtually impossible to get away from screens in our society. They’re everywhere and largely unavoidable as many people use screens to do their jobs, schedule appointments, exercise, relax and socialize. It can be hard to opt out or minimize screen time when screens have become such a ubiquitous and even necessary part of people’s lives.
The average American spends seven hours looking at a screen daily. Globally, people spend six hours staring at their computers, TVs and mobile devices every day. Screen time hours have only gone up since 2013, increasing by almost 50 minutes per day.
But screen time takes a toll on the brain — especially on young kids and their developing brains. Devices affect young brains on many fronts, including impulse control, sleep, critical thinking, creativity and memory. While screen time can and does enhance young people’s lives, many are inundated with content because of its constant availability and they struggle to take breaks, which hurts their health and well-being.
The growing brain
Most human brains don’t fully develop until they hit about 25. Therefore, it’s important that children and young people are safeguarded from the deleterious effects of screen time. At birth, a healthy baby is equipped with about 100 billion neurons and, once developed, neurons travel to areas in the brain where synapses start to form.
The first five years of a person’s life are crucial because that’s when their brains grow the fastest. A person’s earliest experiences shape their brain, and children’s brains are especially malleable. Scientists think that between birth and age 3, a child’s brain creates one million new neural connections every second. Adults’ brains can’t compete with this growth, because children between the ages of 2 and 3 have twice as many connections in their brains. The first major growth spurt of a child’s brain occurs around age 2 and ends when they’re about 7 years old. In adolescence, kids experience another and final brain growth spurt. During this time, the brain is forming hundreds of millions of neural connections.
The American Academy of Pediatrics recommends strict limits on media consumption via screens for children under 2 and insists that it only take place when an adult is available to “co-view, talk, and teach.” Kids who are 2 to 5 years old shouldn’t be exposed to more than one hour of screen time per day, and for those 5 years and older, parents and caregivers should make sure screen time isn’t affecting crucial activities like “sleep, family time, and exercise.” Tweens and teens can have more choice in what they watch.
We know many parents don’t abide by these guidelines (as it can be hard to limit screen time in such a technology-connected society). But unfortunately, screen time can and does harm brains.
Kids between 24 and 36 months who looked at screens longer did worse when tested on their behavioral, cognitive and social development at 36 months. The rub is that young children don’t actually benefit from learning from a screen – they learn better from in-person interactions. Yet children are being exposed to larger doses of screen time than in years past. For example, a 2019 study showed that kids 2 years and younger were hooked to screens for an average of three hours and three minutes in 2014, while in 1997 that figure was one hour and 19 minutes.
The fully developed brain
After about age 25, the fully developed brain differs from its undeveloped counterpart in a few ways. Adults tend to lead with their prefrontal cortex, so they usually act rationally rather than impulsively. Teenagers, on the other hand, are driven by their emotions (the amygdala). The reason for this is structural — teenage brains are still forming connections between the rational and emotional “departments.”
As we age, our brain starts to shrink in our 30s and 40s, with the process speeding up by the time we’re 60. The frontal lobe (human behavior and emotions) and hippocampus (learning and memory) shrink the most. Other changes as we get older include myelin shrinkage, which decreases processing and cognitive function, neuron death, and the thinning of the cerebral cortex (controls processes such as language, memory, decision-making, reasoning, etc.).
It’s not just kids who fall victim to the harms of screen time.
Adults are negatively affected, too. Screen time before bed can decrease or delay melatonin production, which makes it hard for the brain to want to sleep. Screens are also associated with worsening mental health in adults, especially depression. Surprisingly, the elderly spend the most time in front of screens (10 hours or more). TV watching can especially increase seniors’ risk of dementia and, generally, damage their memory.
Short-term effects of screen time
- Suppresses secretion of melatonin (negatively impacts sleep)
- Releases dopamine (negatively impacts impulse control)
- Increases risk of anxiety and depression with social media use
Long-term effects of screen time
- Premature thinning of brain cortex in children (the cortex controls critical thinking and reasoning)
- Lower structural integrity of white matter (supports “language and emergent literacy skills”) in Pre-K children
- Significant gray matter atrophy in people with online gaming addiction
Tips for mitigating negative effects
- Put your device in another room when you sleep
- No screens one hour before bed
- Limit screen time outside of work
- Replace screen time with time outside and physical activity
- Limit or cut out screens during meals
If you still struggle with your screen time and need help to manage it, Zocdoc recommends getting in touch with a mental health professional like a counselor, psychologist or psychiatrist.