The study, which was published in the International Journal of Psychophysiology, found that the sleeping patterns of children with autism are not the same as those of typically developing children, where researchers saw a significant difference in their brain activities during sleep.
According to the researchers, stage 2 sleep spindles— which are partly responsible for a child’s learning potential and play an important role in taking sleep to deeper phases— are significantly of lesser and shorter frequency in children with autism than in typically developing children.
The researchers believe that this could be because children with autism have atypical cognitive organization, and are convinced that the fact that they process information differently compared to typically developing children also play a role.
According to Hôpital Rivière-des-Prairies Sleep Research Laboratory Director Roger Godbout, PhD:
“This is an important discovery that confirms the major role of sleep in consolidating cognitive abilities.”
“This study establishes beyond a doubt that children and adolescents are particularly affected by a lack of sleep, especially because they are in an important developmental period. This is also an important finding given that 10% to 25% of Canadian children and adolescents — and 45% to 85% of autistic children — have sleep problems.”
The research involved 13 children with autism and 13 typically developing children, all of whom did not complain of difficulties in sleeping. The children were asked to sleep for two consecutive nights in a sleep laboratory where their sleep spindles, sigma activities, and non-rapid eye movements were measured by researchers using an electroencephalogram (EEG).
After spending the nights at the lab, the children were tasked to complete a version of the Wechsler Intelligence Scale for Children–IV test the following mornings for two consecutive days.
The researchers found that even though the children with autism involved in the study spent the same duration of stage 2 sleep as their typically developing counterparts, their sleep spindles were significantly lower.
Lead researcher Sophie Tessier said that the results indicate that cortical functioning in children with autism is different from that of the typically developing ones, even when their sleeping habits appear to be normal. She told:
“Our aim is really to understand what autism is and what its consequences are. We are still wondering about the etiology and what it affects, and so we’re still understanding how the brain network is connected and how it works.”
Source: Medscape: Poor sleep liked to impaired intelligence in children with autism: