Sleep and development
Children's sleep changes in step with their neurological and physical development. Newborns have not yet established a circadian rhythm – it develops gradually during the first months through exposure to light, darkness and social cues.¹
Sleep architecture also differs from that of adults. Infants have shorter sleep cycles and spend more time in REM sleep, which is considered important for brain development.²
Many awakenings occur during transitions between sleep stages or between cycles. The exact cycle length varies between children and ages, and depends on how cycles are measured in studies.
| Age (simplified) | Typical cycle length (approximate) |
|---|---|
| Newborn–3 months | approx. 45–60 min |
| 3–12 months | approx. 50–65 min |
| Toddler | approx. 60–90 min |
| Adult | approx. ~90 min |
Sleep plays a central role in learning and memory. Studies show that infants who sleep shortly after a learning experience remember better than those who are kept awake. During sleep, new memories are consolidated, and this process appears to be particularly important during the rapid brain development of the first years of life.⁴
The ability to fall back asleep independently after a night waking matures gradually with the child's neurological development. Young children have limited capacity for self-regulation, which means they often need help from a parent to return to sleep. This ability develops at different rates and is influenced by both maturation and temperament.⁵
A longitudinal study that followed over 75,000 children found that sleep duration in infancy was associated with cognitive and behavioural development at age 5, but that the association was small and individual variation was large.⁶ Touchette et al. (2007) showed that short sleep before age 3.5 was associated with poorer cognitive outcomes, but also that children's sleep needs vary and there is no single "right" number of hours.⁷
Related
References
- Rivkees, S. A. (2003). Developing circadian rhythmicity in infants. Pediatrics, 112(2), 373–381.
- Roffwarg, H. P., Muzio, J. N. & Dement, W. C. (1966). Ontogenetic development of the human sleep-dream cycle. Science, 152(3722), 604–619.
- Sheldon, S. H. (2014). Development of sleep in infants and children. I: Sheldon, S. H., Ferber, R. & Kryger, M. H. (red.), Principles and Practice of Pediatric Sleep Medicine (2:a uppl., s. 17–27). Elsevier.
- Friedrich, M., Wilhelm, I., Born, J. & Friederici, A. D. (2015). Generalization of word meanings during infant sleep. Nature Communications, 6, 6004.
- Sadeh, A. et al. (2010). Infant sleep predicts attention regulation and behavior problems at 3–4 years of age. Developmental Neuropsychology, 35(6), 627–646.
- Hysing, M. et al. (2014). Trajectories and predictors of nocturnal awakenings and sleep duration in infants. Journal of Developmental & Behavioral Pediatrics, 35(5), 309–316.
- Touchette, É. et al. (2007). Associations between sleep duration patterns and behavioral/cognitive functioning at school entry. Sleep, 30(9), 1213–1219.