Sleep disturbances moderate the association between effortful control and executive functioning in early childhood.

Executive functioning, composed of higher-order cognitive skills, rapidly develops in early childhood and is foundational for school readiness and school-age academic achievement. Identifying constellations of factors that are related to the development of executive functioning may inform interventions that prepare children for academic success. This study examined sleep disturbances as a moderator of the association between effortful control, defined as temperament-based self-regulation, and executive functioning among young children. Multiple regressions controlling for child gender and age and caregiver education tested the study research question. Participants were 54 children (Mage = 4.25 years, SD = 0.98; 56% male, 85% White) and their primary caregivers. Caregivers reported on children's effortful control and sleep disturbances via questionnaire, and executive functioning was objectively measured using two well-validated assessment tools. Results showed that high effortful control was associated with better performance on both executive functioning tasks for children with few sleep disturbances. Effortful control was not related to executive functioning in the context of high levels of sleep disturbances. Thus, children whose caregivers observed them to have a temperamental predisposition for higher self-regulation as well as fewer sleep disturbances had the highest executive functioning, suggesting that better-quality sleep may enhance the association between high effortful control and children's executive functioning. Self-regulation and sleep both are responsive to intervention and may be useful targets to improve executive functioning and in turn academic preparedness and success.