Each night we go through four stages of sleep. The type of sleep can be helpful to think of in two categories: rapid eye movement(REM) and non-rapid eye movement(NREM). Sleep stages 1 to 3 are in the NREM category, and stage 4 is in the REM category. For this summary, we will focus on stage 2, the sleep stage we go into when we nap. In this stage, sleep spindles occur, which are a pattern of brain activity. You can think of them like bursts of frequency waves. Slow spindles are 11-13hz, and fast spindles are higher than 13hz. It has been researched that slow-frequency waves are associated with neurodevelopmental disorders such as dyslexia and individuals who are on the autism spectrum.
Jessica Page, Caroline Lustenerger, and Flavio Frohlich (2018) found that sleep dynamics in infants and toddlers between 12 and 30 months of age can impact their brain maturation. Their brain maturation affects their motor, language, and social skills development as they grow into toddlerhood. This information could help understand sleep dynamics in infants and inspire future research in sleep dynamics in neurodivergent children.
In the study, there were 27 participants. The age range was 12 to 30 months. The participants were divided into two groups; younger than 20 months and older than 20 months. To ensure the participants' safety, they were all screened and tested to ensure they were free of a developmental disability and or at risk of an autism spectrum disorder.
Participants came 30 minutes before their nap time to become comfortable with the space. Before they went to sleep, researchers placed an electrode net on the infant's head. The electrode net was connected to an electroencephalogram. An electroencephalogram is a technological tool that can measure and collect frequency wave data for researchers to detect spindle activity. The results showed that sleep spindles occurred in high and low-frequency waves in the frontal area and posterior area of the brain in both age groups. The frontal and posterior regions of the brain are related to motor skills, language, and social skills. In the younger group, there was a single spindle in the frontal area of the brain 14 hz. In the older group, there was a double spindle around 12 hz to 16 hz in the brain's frontal area, which indicated to researchers how sleep spindles change with physical and neurological maturation.
As adults, we want what is best for our children and future generations, making this research important in developmental science. The more we understand how sleep dynamics in infants impact their maturation into toddlerhood, the more we can understand how to effectively support them as they grow.
Page, J., Lustenberger, C., & Frӧhlich, F. (2018). Social, motor, and cognitive development
through the lens of sleep network dynamics in infants and toddlers between 12 and 30 months of age. Sleep, 41(4). https://academic.oup.com/sleep/article/41/4/zsy024/4835154