The COVID-19 Pandemic and Early Child Cognitive Development: A Comparison of Development in Children Born During the Pandemic and Historical References.

Objective: To characterize cognitive function in young children under 3 years of age over the past decade, and test whether children exhibit different cognitive development profiles through the COVID-19 pandemic.

Study Design: Neurocognitive data (Mullen Scales of Early Learning, MSEL) were drawn from 700 healthy and neurotypically developing children between 2011 to 2021 without reported positive tests or clinical diagnosis of SARS-CoV-2 infection. We compared MSEL composite measures (general cognition, verbal, and non-verbal development) to test if those measured during 2020 and 2021 differed significantly from historical 2011-2019 values. We also compared MSEL values in a sub-cohort comprising infants 0-16 months of age born during the pandemic vs. infants born prior. In all analyses, we also included measures of socioeconomic status, birth outcome history, and maternal stress.

Results: A significant decrease in mean population MSEL measures was observed in 2021 compared to historical references. Infants born during the pandemic exhibited significantly reduced verbal, non-verbal, and overall cognitive performance compared to children born pre-pandemic. Maternal stress was not found to be associated with observed declines but a higher socioeconomic status was found to be protective.

Conclusions: Results reveal a striking decline in cognitive performance since the onset of the COVID-19 pandemic with infants born since mid-2020 showing an average decrease of 27-37 points. Further work is merited to understand the underlying causative factors.