New research reveals infants who nap more have smaller vocabularies and poorer cognitive skills, reflecting their individual cognitive needs. Despite parental anxiety, these children should be allowed to nap as needed, and the study emphasizes understanding a child’s mental age for assessing sleep needs.
Babies that nap frequently tend to have smaller vocabularies and weaker cognitive abilities according to a recent study conducted by the University of East Anglia. This issue is a common concern for parents globally, who often worry about their children’s sleep duration.
But a new study published today reveals that some children are more efficient at consolidating information during sleep, so they nap less frequently. Meanwhile others, usually those with fewer words and poorer cognitive skills, need to nap more frequently.
The research team says that reducing naps for these children will not improve brain development and that they should be allowed to nap as frequently and for as long as they need.
Lead researcher Dr Teodora Gliga said: “There is a lot of parental anxiety around sleep. Parents worry that their kids don’t nap as much as expected for their age – or nap too frequently and for too long. But our research shows that how frequently a child naps reflects their individual cognitive need. Some are more efficient at consolidating information during sleep, so they nap less frequently. Children with smaller vocabularies or a lower score in a measure of executive function, nap more frequently.”
“Young children will naturally nap for as long as they need and they should be allowed to do just that,” she added.
The research team studied 463 infants aged between eight months and three years during lockdown in 2020. Parents were surveyed about their children’s sleep patterns, their ability to focus on a task, keep information in their memory, and the number of words that they understood and could say.
They also asked parents about their socio-economic status – including their postcode, income, and education – and about the amount of screen time and outdoor activities their child engaged in.
Dr Gliga said: “Lockdown gave us an opportunity to study children’s intrinsic sleep needs because when children are in childcare, they rarely nap as much as they need to. Because nurseries were closed, it meant less disturbance to the children’s natural sleep patterns. None of the children taking part were attending daycare. What we found is that the structure of daytime sleep is an indicator of cognitive development. Infants with more frequent but shorter naps than expected for their age had smaller vocabularies and worse cognitive function.”
“We also found that this negative association between vocabulary and frequency of naps was stronger in older children,” she added.
“While the majority of parents told us that their child’s sleep was unaffected by lockdown, parents from lower socio-economic backgrounds were more likely to report a worsening in sleep. Screen time increased during lockdown and outdoor activities decreased but these did not explain differences in children’s sleep. Previous work suggested that caregivers should encourage frequent naps, in preschool children. Our findings suggest that children have different sleep needs – some children may drop naps earlier because they don’t need them anymore. Others may still need to nap past three years of age. In the UK, preschools enrolling three to five-year-olds have no provisions for napping. Caregivers should use a child’s mental age and not chronological age to ascertain a child’s sleep needs,” she concluded.
Reference: “More frequent naps are associated with lower cognitive development in a cohort of 8–38-month-old children, during the Covid-19 pandemic” by Teodora Gliga, Alexandra Hendry, Shannon P. Kong, Ben Ewing, Catherine Davies, Michelle McGillion and Nayeli Gonzalez-Gomez, 27 July 2023, JCPP Advances.
DOI: 10.1002/jcv2.12190
The study was led by UEA in collaboration with researchers at the University of Oxford, Oxford Brookes University, the University of Leeds, and the University of Warwick. It was funded by the Economic and Social Research Council (ESRC).
