Kids, when mom says it’s time for bed, know that she’s only trying to make you smarter. New findings by a group of Canadian researchers add to the growing body of evidence that sleep plays a crucial role in mental development. The study shows that quality of sleep can have a direct effect on intelligence and cognitive development in children with autism and in typically developing children.

Autism spectrum disorder, often just called autism, is the fastest growing developmental disorder in the United States, affecting about one in 68 children. Autism is characterized by impaired social development and interaction, making it difficult for children to form relationships and communicate. Difficulty sleeping is one comorbidity of autism, meaning that autism and difficulty sleeping occur simultaneously in a large majority of children with autism (an estimated 44-83% of autistic children).

The researchers used electroencephalography (EEG) to measure brain waves while the children in their study slept. Thirteen typically developing (TD) children and 13 autistic children were selected to participate in the study, and all participants had no known sleep difficulties and normal IQ levels. Participants were put on a regular sleep schedule for two weeks and then had measurements taken for two consecutive nights.

 An example of the sensors used to measure brain waves using EEG.

Image Source: Getty Images News | Oli Scarff

The researchers were specifically looking for sleep spindles, a characteristic brain wave seen from the EEG measurement that signals the transition from Stage 1 sleep to Stage 2 sleep, where we spend the majority of our time when asleep. It has been previously researched that the number and activity of sleep spindles are important for learning.

Results showed that in both groups of children, sleep spindles were positively correlated with higher IQ test scores. In the TD children, higher scores were associated with sleep spindle duration, while in autistic children, higher scores were associated with the density and number of sleep spindles. In general, the sleep spindles in autistic children were shorter and occurred less often than in TD children, even though the autistic children did not have known sleep difficulties. These differences highlight fundamental differences in the way autistic children process and organize information, and that this activity occurs in different brain regions in TD versus autistic children.

This research highlights the need for proper sleep for all children, and suggests that sleep treatment for autistic children may be helpful in treating the developmental issues these children face.

Feature Image Source: Sleep by PROTheGiantVermin

Alex Kim

Author Alex Kim

Alex is a third year student at UC Berkeley studying Molecular and Cell Biology and Public Health and minoring in Music. He hopes to go to medical school and to pursue a career in surgery. In his free time, Alex enjoys playing piano and guitar, running, golfing, eating (everything), and watching movies.

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