Over the past year and a half or so, families have dealt with varying degrees of lockdowns, which included school closures and stay at home orders, brought on by the COVID-19 pandemic. One thing researchers have now been able to investigate is the effects of lockdowns on childhood language development. Here we’ll review the new science and discuss how you can improve your toddler’s language development any time—pandemic or not.
In early March, an international team of researchers posted a preprint—a type of scientific paper that has not yet been officially peer reviewed—on the website PsyArXiv.  Since it has not yet been reviewed officially by other scientists, the findings should be interpreted cautiously, but what the team of researchers found is that what happened during COVID-19 lockdowns had a large impact on child language development.
For the study, more than 70 developmental psychologists, linguists, and other researchers analyzed language development in 1,742 8 to 36 months old children from 13 countries and across 12 languages. The team recruited caregivers (mostly parents) from around the world to take an online survey about their children’s vocabulary at the beginning of daycare closures (around March 2020) and another survey when daycares reopened (as late as September 2020).
In addition to asking about the children’s receptive and expressive language—that is, how much they understand and how much they speak—the initial questionnaire also included demographic information about child age, family income, and parent education level. The follow up questionnaire solicited information about what activities children and parents participated in during lockdown.
The interpretation of the questionnaires revealed that children who watched less TV, including cartoons and baby shows, and whose parents read to them more showed larger improvements in their vocabularies than children who were read to less and had more passive screen time. Interestingly, most children showed some degree of vocabulary improvement during lockdown.
In a Twitter thread describing the work, senior author Julien Mayor, a developmental psychologist at the University of Oslo, explained that there are a couple of possible explanations of this general phenomenon of children learning more words. “Were caregivers more aware of their child’s language during lockdown? Did vocabulary development benefit from this unprecedented period of interaction between caregivers & their children?” he asked. “These two interpretations are not mutually exclusive: greater knowledge of children’s vocabulary allows caregivers to fine-tune their input to the child, in turn potentially leading to better outcomes.” 
In the PsyArXiv study, the researchers excluded participants in bi- or multilingual households, instead focusing on families where the primary language was spoken at least 90 percent of the time. In another study, published in Frontiers in Psychology in July, a group of researchers based at the University of Delaware and San Jose State University in California tested language acquisition in young children in bilingual households, where both Mandarin and English are spoken. 
The researchers in the Frontiers study used parent questionnaires and visual and audio child comprehension activities to compare language acquisition in two groups of 38 children, specifically four- to eight-year-olds, one during, when stay-at-home orders were likely to be in place, and one before the COVID-19 pandemic. They found that children during the pandemic experienced a Mandarin language environment that was richer and also were more likely to use Mandarin themselves, compared to their peers before the pandemic, whose environment and language use was weighted toward English.
What does all this mean? Basically, regardless of whether your family speaks one language or more and the age of your babies, it helps to speak and read to your children, early and often. As this blog post from The Pulse makes clear, early reading has a variety of benefits for your child, including fostering language development.
- Kartushina et al., “COVID-19 first lockdown as a unique window into language acquisition: What you do (with your child) matters,” PsyArXiv. doi:10.31234/osf.io/5ejwu, 2021.
- Mayor (@julien__mayor), “A year after launching the project, it is a great pleasure to announce that we have a preprint…” Twitter, 8 March 2021, twitter.com/julien__mayor/status/1368948372971913216.
- Li et al., “The Bilingual Home Language Boost Through the Lens of the COVID-19 Pandemic,” Frontiers in Psychology, doi:10.3389/fpsyg.2021.667836, 2021.