Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)

First Advisor

Walter Buboltz


ABSTRACT The Centers for Disease Control and Prevention (Y. Liu et al., 2016) reports that 34.8% of adults living in the United States of America are getting less than their recommended amount of sleep per night. Additionally, the National Sleep Foundation (2014) reports that 35% of adults have poor sleep quality. Sleep problems appear most prevalent in young adults (Hershner, 2015). Rates of type 2 diabetes mellitus are also on the rise in this specific population (Kaufman, 2002). Interestingly, research has consistently found that both sleep quantity and quality are associated with glucose levels (Ip & Mokhlesi, 2007; Padilha et al., 2011; Taub & Redeker, 2008). Further, both sleep quantity and quality, as well as glucose, can have a significant effect on cognitive performance (Alhola & Polo-Kantola, 2007; Zilliox et al., 2016). The purpose of the present study was to investigate the mediating effect of glucose on the relationship between sleep and cognitive performance. Sleep included sleep quantity and quality. Cognitive performance included both sustained attention and visuospatial working memory. It was predicted that sleep would be positively related to cognitive performance, and negatively related to glucose levels. It was also predicted that glucose levels, even in a prediabetic range, would be negatively related to cognitive performance, and that this would mediate the relationship between sleep and cognitive performance. To test these hypotheses, data were collected from 82 young adults. Participants answered demographic questionnaires, and surveys assessing their sleep quantity and quality. They then had their glucose levels assessed via finger-stick glucose monitoring. Following this, they completed computerized tasks measuring sustained attention and visuospatial working memory. A hierarchical multiple regression analysis was conducted to test the proposed hypotheses. After cleaning, 81 cases were found to be viable for analysis. Results obtained were in partial support of hypotheses. Poor sleep quality, as measured by the Adult Sleep-Wake Scale (ADSWS; Fortunato et al., 2008), was found to be associated with decreased visuospatial working memory (β = -.02, p = .039). No other hypotheses were supported, though some trending results were found. It is believed had a larger and/or more diverse sample been used, more significant results would have been found. Implications exist not only for students, but for all young adults. They are likely to be of interest to young adults, as well as those working with young adults. This includes mental health professionals, various medical personnel, teachers, and school administrators.