How Screen Exposure Alters Child Development, Expert Warns

Child neuropsychologist Fanny Wong explains the effects of excessive device use on children’s attention, sleep, and emotions.

November 25, 2025 | Montemorelos, Nuevo León, Mexico | Laura Marrero and IAD News Staff

Prolonged exposure to screens, video games, and mobile devices has become one of the main concerns among child mental health professionals, Child neuropsychologist Fanny Wong said during a recent presentation at Montemorelos University. Far from being a minor issue, children’s digital habits are shaping their cognitive, emotional, and behavioral development in ways we still do not fully understand, but which are already beginning to show visible consequences, she explained.

A specialist in childhood development and brain functions, Wong explains that the experiences lived during the early years of life determine much of our future emotional and behavioral structure. “Childhood is the ground on which we will walk for the rest of our lives,” Wong states, emphasizing that digital overexposure interferes with key stages of brain maturation—especially in the formation of attachment, attention, and language.

Several recent studies confirm that children under two years of age do not yet have the neurological maturity to properly process screen stimulation. Even so, many babies are exposed to devices even while they are being fed, which replaces the visual and physical contact needed for emotional development. In preschool children, excessive exposure has been linked to lower myelination of white matter, affecting brain organization and language learning.

As children grow, the effects diversify. Physically, cases of obesity, eye strain, headaches, and postural problems increase. Cognitively, constant screen use fragments attention and reduces the ability to maintain sustained concentration, generating symptoms similar to attention deficit disorder. In addition, the developing brain—exposed to rapid, constantly changing stimuli—loses the ability to remain calm, to plan, and to control impulses.

Wong warns that these alterations directly impact academic performance. “A child who spends hours in front of a tablet often lacks structure and habits, which is reflected in their organization, behavior, and school performance.” Fine motor skills, for example, have been affected by the decline of handwriting practice, a habit that stimulates key brain areas related to reasoning and coordination.

On the emotional level, highly addictive video games—such as Fortnite or Minecraft—have created dependency patterns and impulsive behaviors comparable to addictions. “When devices are taken away, many children show irritability, anxiety, or even withdrawal symptoms,” Wong explains. These behaviors intensify in adolescents with low frustration tolerance or with conditions such as ADHD or autism spectrum disorders, where digital exposure can increase aggression, isolation, and anxiety.

The specialist also notes the social and emotional impact of this dynamic. “Many young people are growing up without developing skills of reciprocity or human interaction. They are learning to relate more to a screen than to a person.” This disconnection affects their emotional intelligence and their ability to build real relationships.

At the same time, exposure to inappropriate content online and on social media contributes to problems with self-esteem, body-image distortion, anxiety, and depression. “The Instagram filter does not look like a real face, and that difference is generating dissatisfaction, especially in teenage girls,” Wong comments. Likewise, early access to sexual or violent material can alter identity development and behavior, and increase the risk of abuse or unsafe situations.

One of the most alarming effects, she notes, is sleep disruption. The blue light emitted by screens inhibits melatonin production and affects sleep quality. “A teenager should sleep between eight and ten hours, but many sleep four. Sleep is the best stabilizer of mood and cognitive performance. Without adequate rest, the entire system becomes dysregulated.”

Given this outlook, Wong emphasizes that the solution is not to demonize technology, but to regulate its use and provide emotional support to children. She recommends that parents set schedules, create screen-free spaces, limit use before bedtime, and prioritize educational content. For children under 18 months, the World Health Organization completely discourages the use of devices, except for supervised video calls.

Beyond screen time, the specialist highlights a key factor: the context and quality of the experience. “If a child lives in an environment of yelling or lack of attention, the device becomes an emotional refuge. It’s not only about how long they spend in front of the screen, but also how and why they use it.”

The role of psychologists and educators, Wong says, should focus on psychoeducation and family guidance. Promoting clear limits, encouraging open dialogue, and teaching parents to understand their children’s emotional and cognitive nature are fundamental steps in preventing harm. “Parenting should not be improvised. Psychoeducation is teaching. If we help parents understand and establish structure, we help children develop healthily.”

Finally, she highlights that reducing technological dependency is not impossible. “If a child has spent a lot of time in front of screens, use can be reduced gradually, and recreational, sports, or artistic activities can be encouraged to stimulate interaction with the environment and with other people.”

This reflection was part of the presentation “Effects and Risks of Exposure to Screens, Video Games, and Mobile Devices in Childhood and Adolescence,” delivered by Fanny Wong during the Psychology Congress of Montemorelos University, in Mexico, held on October 22-23, 2025, under the theme “Therapeutic Skills and Tools: Challenges of Contemporary Psychology.”

Fanny Wong holds a degree in Education with a specialization in Educational Psychology from Montemorelos University. She is a child neuropsychologist with over 20 years of clinical experience in diagnosing and treating developmental, learning, and behavioral disorders. She has collaborated in early-intervention and family-guidance programs in educational and health institutions and has given lectures on neurodevelopment and conscious parenting in various national and international forums.

Lisandra Vicente and Brenda Cerón contributed to this article.