Altered Non-Visual Photoreception in Patients With Glaucoma: Impacts on Sleep, Alertness, Mood, and Cognition

The goal of this study is to understand how light sensitivity in the eye affects sleep, mood, alertness, and cognition in adults with glaucoma compared to healthy individuals aged 45-75 years. The main questions it aims to answer are: 1. Do patients with glaucoma experience poorer sleep, mood, alertness, and cognitive function than age-matched healthy adults? 2. Are these changes related to reduced light sensitivity in special retinal cells called intrinsically photosensitive retinal ganglion cells (ipRGCs), lost in glaucoma? 3. Can exposure to safe, full-spectrum indoor light help improve these functions? Researchers will compare patients with glaucoma and age-matched healthy controls to see if differences in light sensitivity can explain changes in non-visual light responses (i.e., sleep, mood, alertness, and cognition) and whether full-spectrum light exposure can enhance alertness and wellbeing. Participants will: 1. Complete eye exams and baseline questionnaires about their sleep, daytime sleepiness, mood, and wellbeing. 2. Wear a wrist-worn device for 8-16 days to record their sleep patterns and light exposure. 3. Visit the laboratory for cognitive and attention tests following exposure to two lighting conditions (randomized, cross-over): * Standard indoor light (\~300 lux) * Full-spectrum light (\~1000 lux) This study will help researchers understand how glaucoma affects the brain beyond vision and explore whether light-based interventions can improve quality of life for people living with glaucoma.