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Updated: May 15, 2026
Eye Tracking Young Children with Autism
Published on: March 27, 2012
First night effect analysis in a cohort of young children with autism spectrum disorder
Ashura Buckley1, Katherine Wingert, Susan Swedo
1National Institute of Mental Health, Pediatrics and Developmental Neuroscience Branch, Bethesda, MD 20982, USA. Shu.buckley@nih.gov
Insights
The first night effect (FNE) was present in young children with autism for some sleep measures, but not for total sleep time or REM sleep. This suggests a single polysomnogram night may suffice for evaluating these autism sleep parameters.
Area of Science:
- Pediatric Sleep Medicine
- Autism Spectrum Disorder (ASD) Research
- Neurodevelopmental Disorders
Background:
- The first night effect (FNE) is a phenomenon where sleep patterns differ on the first night of a laboratory study compared to subsequent nights.
- Understanding FNE in children with autism spectrum disorder (ASD) is crucial for accurate sleep assessment.
- Previous research on FNE in pediatric populations with neurodevelopmental conditions is limited.
Purpose of the Study:
- To investigate the presence and characteristics of the first night effect (FNE) in young children diagnosed with autism spectrum disorder (ASD).
- To determine if sleep patterns on the first night of a polysomnography study differ significantly from the second night in this population.
- To assess the implications of FNE for the interpretation of sleep data in children with ASD.
Main Methods:
- Polysomnography (PSG) data were collected over two consecutive nights in a sleep laboratory setting.
- The study included 15 children aged 2-10 years with a confirmed diagnosis of ASD.
- Sleep parameters analyzed included wake after sleep onset, sleep stages (including REM sleep), total sleep time (TST), and sleep efficiency.
Main Results:
- A significant first night effect (FNE) was observed for wake after sleep onset minutes, stage 2 sleep, and overall sleep efficiency.
- However, no significant FNE was found for REM sleep parameters (percentage or latency) or total sleep time (TST).
- These findings indicate a differential impact of FNE across various sleep metrics in children with ASD.
Conclusions:
- The absence of a significant FNE for total sleep time (TST) and REM sleep parameters in children with autism suggests these metrics may be reliably assessed with a single night of polysomnography.
- This finding has practical implications for optimizing sleep studies in pediatric ASD populations, potentially reducing participant burden.
- Further research is warranted to explore the specific factors contributing to the observed FNE patterns in children with ASD.
Study Objectives:
To evaluate for the first night effect (FNE) in a group of young children with autism.
Design:
Analysis of polysomnographic data from a 2-night sleep laboratory study.
Setting:
Clinical Center of the National Institutes of Health.
Patients Or Participants:
15 children (aged 2-10 years) with a diagnosis of an ASD.
Interventions:
None.
Measurements And Results:
Polysomnographic analysis showed the presence of a FNE for wake after sleep onset minutes, stage 2, and sleep efficiency, but not for REM sleep parameters or TST.
Conclusions:
In this 2-night polysomnographic analysis of sleep stages in young children with autism, we did not find the expected second night increase in total sleep time or REM sleep percentage or a decrease in REM sleep latency. This lack of an FNE for TST and REM parameters suggests that a single-night polysomnogram may be sufficient to evaluate children with an ASD for TST or REM parameters.
