How COVID Changed What We Know About Children's Language

The RESONANCE Study: The Data That Made Headlines

In 2022, a study from Brown University's RESONANCE consortium sent shockwaves through the parenting world. Researchers led by Sean Deoni compared neurocognitive scores from 700 children assessed between 2011 and 2021 using the Mullen Scales of Early Learning — a well-validated measure of cognitive, verbal, and motor development. The findings were striking: children born during the pandemic showed significantly lower scores in verbal development, non-verbal development, and overall cognitive functioning compared to children born in the decade before. The declines weren't small. And they appeared even after controlling for age, sex, socioeconomic status, and maternal stress. Boys appeared to be hit harder than girls, and children from lower socioeconomic backgrounds showed the steepest drops. But here's the critical context that many headlines missed: this study measured children's performance at a single point in time. It told us where pandemic-era children were, not where they'd end up. Development isn't a snapshot — it's a trajectory. And trajectories can change, especially with the right support.

It Wasn't the Virus — It Was the Environment

One of the most important findings came from Shuffrey and colleagues, published in JAMA Pediatrics in 2022. Their study of 255 infants examined whether prenatal exposure to maternal SARS-CoV-2 infection affected neurodevelopment at six months. The answer? No. Prenatal COVID exposure was not associated with differences in neurodevelopmental scores. But here's what was: being born during the pandemic itself. Both exposed and unexposed infants born during the pandemic period scored lower on gross motor, fine motor, and personal-social subdomains compared to a pre-pandemic cohort. This is a crucial distinction. The virus itself wasn't the problem — the pandemic environment was. Reduced social interactions, increased parental stress, limited access to healthcare and early intervention services, fewer opportunities for play with other children — these environmental factors appear to be the primary drivers of the developmental differences researchers observed.

• Parental stress and mental health challenges during lockdowns affected the quality of parent-child interactions
• Reduced access to pediatric well-visits meant fewer opportunities for developmental screening
• Closed daycare and preschool programs eliminated key language-rich environments
• Social distancing limited children's exposure to diverse communication partners

The Mask Question: Less Scary Than You'd Think

Parents worried a lot about face masks — and understandably so. We know that babies and young children rely on visual speech cues (watching lip movements, facial expressions) to help them learn language. So what happened when adults started covering their faces? Research published in Frontiers in Psychology explored how face masks affected children's language processing and emotion recognition. The findings were more reassuring than many expected. While masks did reduce children's ability to use visual speech cues, the impact on core language comprehension was relatively modest. Children showed remarkable resilience in processing spoken language even when visual cues were obscured. The bigger impact was on emotion recognition — children had more difficulty reading happy and sad expressions through masks. Older children adapted more successfully than younger ones. This aligns with what we know about human language processing: while visual cues are helpful, they're supplementary. The auditory speech signal carries the lion's share of linguistic information. Children's brains are remarkably good at extracting meaning from imperfect input — it's actually one of the things that makes human language acquisition so extraordinary.

Social Isolation: The Real Culprit

If one factor emerges as the most significant contributor to pandemic-era language delays, it's social isolation. A 2025 scoping review by Zuniga-Montanez and colleagues, published in the Journal of Child Psychology and Psychiatry, synthesized the peer-reviewed literature on how the pandemic affected young children's language environments and development. Their findings paint a clear picture: literacy, school readiness, and general communication skills were all negatively affected. Most strikingly, pre-pandemic infants as young as four months could segment words in the speech stream — a foundational skill for language learning. Their pandemic-era counterparts couldn't do so even at twelve months. The mechanism makes sense when you think about it. Language is fundamentally a social tool. Babies don't learn language from overhearing it — they learn it through interaction, through serve-and-return exchanges with responsive caregivers, through the messy, chaotic, wonderful process of being around other people who talk to them, around them, and with them. When you reduce the number and variety of those interactions, you reduce the raw material the developing brain needs to build its language system.

• Children who attended more in-person preschool during the pandemic had better language and literacy outcomes
• Peer interaction — not just adult-child interaction — plays a unique role in language development
• Children from lower socioeconomic backgrounds were disproportionately affected by reduced social contact
• Virtual interaction (video calls) did not fully compensate for the loss of in-person social engagement for young children

The Silver Linings Were Real

The pandemic story isn't all bad news. Some families — particularly those where parents worked from home and had stable employment — reported more quality time with their children than ever before. Without commutes, social obligations, and packed schedules, some parents found themselves engaging in more one-on-one play, more reading, and more conversation with their little ones. Research found that while parental engagement tended to decrease in the later stages of the pandemic (as fatigue and stress accumulated), the availability of learning resources like books actually increased over the period. Some children thrived in the quieter, less overscheduled home environment. This highlights an important truth about language development: quantity of social exposure matters, but quality of interaction matters more. One parent engaged in rich, responsive conversation with a child can provide more language-building input than a crowded, noisy playroom where nobody is really tuning in to the child. The pandemic, for all its hardships, reminded many families of the power of simple, present, connected interaction.

What Parents of Pandemic Babies Should Watch For Now

Children born between 2020 and 2022 are now preschoolers and early elementary students. The good news is that most children are resilient, and many are catching up as social environments have normalized. But research consistently shows that children who were already at developmental risk before the pandemic — those from lower-income families, those with pre-existing developmental differences, those with limited access to enriching environments — fell further behind and may need more targeted support to close the gap. Speech-language delay identification more than doubled comparing pre- versus post-pandemic among children ages zero to twelve, according to a comparison by Komodo Health. This doesn't necessarily mean more children have disorders — it may partly reflect the backlog from missed screenings during lockdowns. But it does mean that if you have concerns, now is the time to act.

• Watch for vocabulary that seems behind peers — a 3-year-old should be using hundreds of words and short sentences
• Notice whether your child engages in back-and-forth conversation or mostly talks in isolation
• Pay attention to social communication: does your child make eye contact, take turns, and respond to others?
• If your child was born during the pandemic and hasn't had a developmental screening recently, ask your pediatrician for one
• Don't wait to "see if they grow out of it" — early intervention services are most effective when started early