New study from the University of Montreal and Hôpital Rivière-des-Prairies was published in International Journal of Psychophysiology.

Scientists found that just one night of poor sleep significantly decreases performance on intelligence tests in children with autism spectrum disorder (ASD).

Same results found for non-ASD neurotypical children. Observed the EEG measures of 13 autistic children and 13 neurotypical children. Mean age of 10 years old. Without an intellectual deficiency or sleep problem and were not on medication.

Found that disruptions in protective brain waves during sleep are associated with lower results on verbal IQ tests

The brain waves demonstrating good sleep were measured in a laboratory. Markers of light sleep known as "sleep spindles." Occur during a sleep phase that repeats throughout the night. Body metabolism slows and the brain rests. This is different from REM sleep, when the brain is active and dreams. The more a child had these good brain waves throughout the night, the better the child was at cognitive tasks.

Wechsler Intelligence Scale for Children was most significant. Quality of sleep over the whole night promotes good intellectual functioning. This is applicable to both groups of children studied. The relationship between sleep waves and cognitive performance differs between neurotypical and autistic children.

Study establishes that children and adolescents are particularly affected by a lack of sleep but however is still in developmental period.

Currently 10% to 25% of Canadian children and adolescents have sleep problems and 45% to 85% of autistic children have sleep problems.