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

Inclusion Criteria: * Patients with glaucoma must meet all of the inclusion criteria to participate in this study. * Patients diagnosed with primary open-angle glaucoma (POAG), as indicated by Humphrey Visual Field (HVF) mean deviation (VFMD) scores better than -12 dB in at least one eye during their most recent clinic visit. * Patients having spared central vision. * Patients aged 45 to 75 years old. * Patients with a best-corrected visual acuity better than 6/12 * English-speaking patients Healthy controls must meet all of the inclusion criteria to participate in this study: * Participants aged 50 to 70 years old. * Participants with a best-corrected visual acuity better than 6/12 * Normal ophthalmic examination * English-speaking participants Exclusion Criteria: * All subjects (patients and controls) meeting any of the exclusion criteria at baseline will be excluded from participation: * Participants with myopia exhibiting a refractive error exceeding -8.00 diopters (D) * Participants with a history of complicated previous intraocular surgery * Participants taking alpha-adrenergic agonist eye drops or other systemic medications or drugs that could affect the pupillary response * Participants with any past or current ocular condition (i.e., age-related retinal diseases (e.g., age-related macular degeneration), retinal pigment epithelium diseases (e.g., Best's disease), diabetic retinopathy, or other optic or generalized neuropathies, significant ocular trauma, or any eye condition affecting fixation (eg. Nystagmus)). * Participants diagnosed with cataracts at NS3+ (Nuclear Sclerosis) and above, as well as those with Posterior Subcapsular (PSC) cataracts * Participants with clinically diagnosed psychiatric or neurologic disorders, including cognitive impairment or dementia * Participants with diagnosed mood disorders * Participants engaged in night shift work within the past three months, are currently using sleeping pills, or have recently travelled across timezones within a month prior to the study * Participants with obstructive sleep apnea * Participants with abnormal auditory function * Participants with impaired color vision * Pre-menopausal women (last menstrual period \< 1 year) (If applicable) * Patients having unilateral glaucoma, congenital glaucoma, non-glaucomatous optic neuropathy, abnormal central vision * Diabetics on treatment