Date of Project


Document Type

Honors Thesis

School Name

College of Arts and Sciences



Major Advisor

Dr. Christy Wolfe

Second Advisor

Dr. Joy Jacobs-Lawson


A necessary biological process, sleep is foundational to health and wellness with numerous functions throughout the body (Ramar et al., 2021). Sleep and the circadian rhythm, however, are highly affected by light because the suprachiasmatic nuclei (SCN) regulate hormones related to sleep based on light processed by special cells in the retina (Wirz-Justice, 2009). The purpose of this research project was to explore the associations between blue light exposure in the hours before bedtime, self-reported sleep quality, and measures of mood, mental well-being, and cognitive function in college students. Thus, one goal of this research project was to demonstrate an association between blue light exposure and sleep quality with a sample of college-aged individuals who spend a considerable amount of time on blue-light emitting electronic devices – and to explore this association in the Covid-pandemic environment. Associations between sleep quality and perceptions of stress, mood, and cognitive function were also explored. This project employed an online, anonymous survey methodology and recruited college student participant volunteers (n = 204) via word of mouth at Bellarmine, through the announcements of willing professors, and postings on social media sites. Results of this study showed a sizeable frequency of students who use smart phones within the hour before bed (over 96%) with the most frequent screen time activity being social media use. An association between nighttime screen exposure and poor sleep quality (β = .20, p = .003) was demonstrated which in turn negatively predicted all measures of mental and emotional well-being (β = -.49, p < .001). This study can be used to educate college students on the potential negative effects of nighttime blue light exposure on their sleep quality, emotion, and cognition.

Available for download on Wednesday, May 17, 2023