Effects of Total Sleep Time and Sleep Schedule Alignment on Cognitive Functioning in Adolescents

Abstract

Recently, adolescent sleep research has produced conflicting results about the effect of sleep on cognition in this age group. Some have proposed that adolescents possess a mechanism for cognitive resiliency that allows their cognitive performance to remain stable despite restricted sleep. Others maintain that the conflicting outcomes stem from the sleep/wake parameters traditionally used in sleep research that are rarely adjusted to allow for natural adolescent sleep rhythms, which may be masking the true effect of inadequate sleep on adolescent cognitive functioning. This study aims to elucidate these two theories by comparing both sleep time and sleep rhythm alignment with cognitive functioning. We tracked 16 adolescents' sleep for one week and determined their sleep time and whether they were sleeping in alignment with their natural sleep rhythms. Both of these variables were then compared to subjects' performance on an n-back task of working memory on Monday morning. The results showed that neither sleep amount nor natural sleep rhythm alignment were able to predict any measure of the working memory test. These results support the theory of a cognitive resiliency mechanism in adolescents, and do not support sleep rhythm misalignment as a significant confounding variable in previous adolescent sleep studies.