0122 Sleep Moderates Arousal and Executive Functioning in Autistic Children

Abstract Introduction Arousal dysregulation (over- or under-arousal) and executive functioning (EF) difficulties are positively correlated and often experienced by autistic children. Arousal and task performance (e.g., EF) are connected, such that there is an optimal arousal level for an optimal performance and arousal dysregulation reduces task performance. Up to 80% of autistic children experience sleep problems, and sleep problems are positively correlated with arousal dysregulation and EF difficulties. Thus, sleep may moderate the relationship between arousal and EF in autistic children. Given that sleep is modifiable through behavioral sleep treatment, it is important to better understand these relationships in autistic children. This study examined whether subjective and objective sleep moderated the relationship between HRV and EF among autistic children. Methods Children with autism spectrum disorder (N=65), verbal IQ >70, and parent reported sleep complaints (Mage=8.95, SD=2.01, range 6-12; 74% male) completed 14 days of sleep diaries (with parental assistance) and actigraphy, Holter Monitoring (8-mins at rest), and the Connor’s Continuous Performance Test (CPT)-III (ages 8+) or Connor’s Kiddie CPT-II (ages 4-7.11). Multiple regressions (SPSS PROCESS) examined whether sleep (subjective/objective wake after sleep onset-WASO, total sleep time-TST) moderated associations between arousal (standard deviation of normal-to-normal R-R-intervals-SDNN, proportion of adjacent R-R intervals differing by >50 ms-PNN50) and EF (CPT-perseverations, omissions, commissions). Analyses controlled for age. Results Objective WASO moderated associations between SDNN and CPT-perseverations (R2=.27, p=.03). At highest WASO, higher SDNN was associated with greater perseverations, t(1,65)=5.00, p=.029. Subjective TST moderated associations between PNN50 and CPT-perseverations (R2=.32, p=.01). At highest TST, higher PNN50 was associated with greater perseverations t(1,65)=4.27, p=.04. Conclusion When autistic children sleep more and have greater sleep fragmentation, EF may suffer (i.e., greater response repetition) if arousal is not high enough. While our finding for sleep fragmentation (indicative of poor sleep) is consistent with existing literature, that for greater sleep (indicative of better sleep) is not. This suggests the relationships amongst these constructs are complex in autism, and more research using longitudinal and experimental methodology and perhaps even examining other aspects of TST (e.g., variability) are needed. Support (if any) DOD Autism Research Program (McCrae, PI; W81XWH2010399); NIAMS (R01AR055160/R01AR005160- S1; P1,McCrae).