Children who were two and three years old during the coronavirus lockdown have a smaller vocabulary when compared with children in the same age group before 2020, research by the University of Utrecht has shown.

“We concluded that the number of words these toddlers knew after coronavirus was significantly smaller than that of children who had reached the toddler stage before the pandemic,” researcher Anika van der Klis told broadcaster NOS.

The most likely cause is that lockdown limited the number of people the children came into contact with, Van der Klis said.

“Children don’t just learn from their parents but also from grandma and granddad and other children. It’s very important that children chat with lots of different people. One person may say “mug” while another says “cup”. Hearing all these different words makes for a bigger vocabulary,” she said.

The lack of outings, to a playground or swimming pool, each with its particular vocabulary, also played a role, Van der Klis said.

In babies, lockdown slowed down the development of social-emotional skills which children need later on to be able to make friends, work together and resolve conflicts.

Not having these skills can affect mental health and school performance. A possible cause may be the stressful circumstances in which expectant mothers found themselves during lockdown.

Researchers said it is likely that children will suffer longer-term effects from the lack of stimulation and are calling for extra language and reading support for this group.  “A young child needs words, not only to make friends and learn social skills but also to understand what the teacher is saying,” Van der Klis said.

To stimulate children’s social-emotional development, researchers recommend less screen time. “Parents think children learn language and social-emotional skills from watching tv but that is not the case. They learn through playing with their friends,” Van der Klis said.