Neurobehavioural links from infant screen time to anxiety

Infant screen time is linked to many negative outcomes, including anxiety, but the underlying neural correlates and pathways remains understudied. We aimed to assess the directional association between infant screen time, development of brain network topology, decision-making behaviour and anxiety symptoms in adolescence.

Using data from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort study, we examined the effects of total daily screen time for infants on developmental outcomes using structural equation modelling. Specifically, we looked at the developmental slopes of network integration for the seven major brain cortical networks between ages 4.5, 6.0, and 7.5, decision-making behaviour assessed using the Cambridge Gambling Task (CGT) and anxiety symptoms assessed using the Multidimensional Anxiety Scale for Children, 2nd Edition (MASC). This study included 168 children from the GUSTO cohort with data on infant screen time (ages 1-2), diffusion MRI (ages 4.5-7.5), data on decision-making performance (CGT at age 8.5), and anxiety symptoms (MASC at age 13). Brain network integration was derived from diffusion MRI and each participant's developmental slopes were modelled using latent growth models. Structural equation modelling assessed pathways linking early screen time to adolescent anxiety, mediated by brain network development and decision-making.

Higher infant screen time was associated with a steeper decline in visual-cognitive control network integration from ages 4.5-7.5 years (β = -1.03 (-1.61, -0.46)), which mediated increased CGT deliberation time at age 8.5. Deliberation time, in turn, was associated with greater anxiety symptoms at age 13. A full serial mediation pathway was significant, linking infant screen time to later anxiety via accelerated brain network maturation and decision-making behaviour (β = 0.033 (0.002, 0.160)).

Higher infant screen time is linked to accelerated topological maturation of the visual and cognitive control networks, leading to prolonged decision latency and increased adolescent anxiety. Sensory processing impairment may underlie this novel neurodevelopmental pathway, highlighting a potential target for early intervention.

This research was supported by the Singapore National Research Foundation, Singapore Ministry of Health's National Medical Research Council (NMRC), Singapore, Institute for Human Development and Potential, Agency for Science, Technology and Research, Singapore, the Hope for Depression Research Foundation, USA, the Toxic Stress Network of the JPB Foundation, USA, and the Jacobs Foundation, Switzerland.