Differences in Sleep Related Learning in Children with ASD and Williams Syndrome

Background: Several factors have been outlined as having a negative impact on cognitive and behavioral functioning
of individuals with Autism Spectrum Disorders (ASD) and Williams Syndrome (WS). Sleep is the main focus of the current study since
a number of studies reported that children with ASD and WS experience severe sleep problems. Since sleep
has been found to play an active role in children’s memory consolidation, it is vital to assess the impact
of sleep on children's functioning.
Objectives: The current study aimed to examine if there were any specific sleep related learning patterns in two developmental disorders, namely ASD and WS. Children in both disorders have been reported to have specific sleep problems: children with ASD often suffer from frequent night wakings, whereas children with WS suffer from sleep onset delay. In both groups, comparison of the sleep-dependent memory consolidation has not been examined.
Methods: Participants included school aged children: 12 typically developing (TD)and 12 children with ASD and 12 children with WS.

Sleep dependent memory consolidation was assessed using an Animal Names task, a child-friendly and engaging declarative memory task. Sleep was further assessed using the Childhood Sleep Habits Questionnaire and actigraphy to objectively measure sleep quality and quanitity.

Results: As expected, TD children had higher scores on the Animal Names task following intervals of sleep, rather than wake, indicating that during periods of night-time sleep children’s memory traces of the animal’s names were strengthened. Similary children with ASD showed similar pattern to the TD group albeit showing poorer performance scores. Children with WS showed a different pattern to both groups. Significant differences in Sleep Duration, Night Wakings were found between the groups. There were large group differences in all sleep variables, showing specific sleep problems in the clinical groups as well as learning patterns when correlated to sleep.

Conclusions: The current study suggests that sleep plays an active role in cognitive functioning in children. The study emphasizes the importance of sleep in children with developmental disorders and its role in the process of learning. It is concluded, that sleep has a strengthening effect on the memories of both TD and children with ASD but not WS.
Gaining a better understanding of the influence of sleep on learning in children is an important factor in order to implement better teaching interventions.