Babies and toddlers who watch television or videos may develop atypical sensory behaviors—unusual ways of perceiving and responding to the world—that mirror traits seen in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). A groundbreaking study from Drexel University and the University of Fukui analyzed data from nearly 1,500 children and found that screen exposure in the first two years of life was directly linked to sensory processing difficulties by age 33 months. How Does Screen Time Affect Sensory Development in Toddlers? Researchers examined how television and video viewing in infants and toddlers influenced their sensory processing abilities—the way children perceive and respond to sights, sounds, textures, and other sensory input. The findings were striking: children exposed to screens showed significantly higher rates of atypical sensory behaviors, including sensation seeking (craving intense stimulation), sensation avoiding (withdrawing from stimuli), and low registration (slower or less sensitive responses to sensory input). The study tracked screen exposure at three critical developmental milestones: 12 months, 18 months, and 24 months. The results revealed a dose-response pattern—meaning more screen time correlated with greater sensory challenges. At 12 months, any screen exposure was linked to a 105% greater likelihood of "high" sensory behaviors related to low registration by 33 months. At 18 months, each additional hour of daily screen time increased the odds of sensation avoiding and low registration by 23%. By 24 months, each additional hour of screen time was associated with a 20% increased odds of sensation seeking, sensory sensitivity, and sensation avoiding behaviors. Why Are Sensory Processing Issues Connected to ADHD and Autism? Atypical sensory processing is far more common in children with autism spectrum disorder and ADHD than in the general population. For children with autism, repetitive behaviors and intense focus on specific interests are highly correlated with how their brains process sensory information. Similarly, children with ADHD often struggle with attention regulation partly because of how they filter and respond to sensory stimuli in their environment. "This association could have important implications for attention deficit hyperactivity disorder and autism, as atypical sensory processing is much more prevalent in these populations," said Dr. Karen Heffler, an associate professor of Psychiatry at Drexel and the lead author of the study. "Repetitive behavior, such as that seen in autism spectrum disorder, is highly correlated with atypical sensory processing. Future work may determine whether early life screen time could fuel the sensory brain hyperconnectivity seen in autism spectrum disorders, such as heightened brain responses to sensory stimulation". What Are Atypical Sensory Behaviors? Atypical sensory behaviors fall into two main categories: hypersensitivity and hyposensitivity. Children with hypersensitivity find certain textures, sounds, lights, or smells overwhelming and distressing—for example, the hum of fluorescent lighting or the feel of certain fabrics against the skin can cause significant discomfort. Conversely, children with hyposensitivity seek out intense sensory experiences, enjoying deep pressure, loud noises, or bright lights as a way to stimulate an under-responsive sensory system. In children already diagnosed with autism spectrum disorder or ADHD, atypical sensory processing can lead to a cascade of challenges: - Emotional Regulation: Irritability and difficulty managing big emotions, which can result in behavioral episodes or meltdowns - Sleep and Eating: Disrupted sleep patterns and eating difficulties due to sensory sensitivities or seeking behaviors - Social Functioning: Increased social problems and difficulty navigating peer relationships - Executive Function: Trouble with planning, organizing, and completing tasks - Mental Health: Higher rates of anxiety and reduced overall quality of life What Does the Research Actually Measure? The study used a standardized assessment tool called the Infant/Toddler Sensory Profile (ITSP) to evaluate how children responded to sensory stimuli. The ITSP measures four key sensory behavior patterns: low registration (being less sensitive or slower to respond to stimuli), sensation seeking (excessive touching or smelling objects), sensory sensitivity (irritation from lights and noise), and sensation avoiding (actively controlling their environment to avoid certain experiences like teeth brushing). Based on the frequency of these behaviors, children received scores in "typical," "high," or "low" categories. The research team analyzed data from the National Children's Study, which tracked 1,471 children (50% male) nationwide between 2011 and 2014. Screen exposure measurements were based on caregiver responses at different age milestones, and researchers accounted for various factors like age, premature birth, caregiver education, race/ethnicity, and the child's engagement in activities like play or walking with the caregiver. Steps to Reduce Screen Time and Support Sensory Development - Follow AAP Guidelines: The American Academy of Pediatrics advises against screen time for toddlers under 18 to 24 months, with limited digital media use for children aged 2 to 5 years. This means prioritizing screen-free time during critical developmental windows - Engage in Active Play: Replace screen time with interactive activities like playing with toys, exploring textures, and engaging in physical movement, which naturally support healthy sensory development - Seek Occupational Therapy: For toddlers already showing sensory processing difficulties, occupational therapists can deliver specialized sensory processing practices designed to help children regulate their responses to stimuli - Provide Parent Education: Parents benefit from learning about sensory-friendly environments and strategies to minimize screen exposure, especially during the critical first two years of life "Considering this link between high screen time and a growing list of developmental and behavioral problems, it may be beneficial for toddlers exhibiting these symptoms to undergo a period of screen time reduction, along with sensory processing practices delivered by occupational therapists," said Dr. Heffler. Why Is This Finding Important Now? The timing of this research is critical. In the United States, children aged 2 and under watched screens for an average of 3 hours and 3 minutes per day in 2014—a dramatic increase from just 1 hour and 19 minutes per day in 1997. Many parents turn to screen time due to exhaustion and a lack of affordable alternatives, making education and support essential. This study adds to a growing body of evidence linking early screen exposure to developmental and behavioral challenges, including language delays, autism spectrum disorder, behavioral problems, sleep disturbances, attention issues, and delays in problem-solving skills. The research suggests that reducing screen time in the first two years of life may help prevent or minimize these sensory processing difficulties. "Parent training and education are key to minimizing, or hopefully even avoiding, screen time in children younger than two years," said Dr. David Bennett, senior author and a professor of Psychiatry in Drexel's College of Medicine. The findings underscore that the choices parents make in the earliest years can have lasting effects on how children's brains develop and process the world around them.
