Abstract
PURPOSE: The Pattern Glare Test (PGT) is a widely used tool for assessing visual discomfort and perceptual distortions elicited by repetitive, high-contrast patterns. It has been applied across diverse populations and research fields, including neuroscience, cognitive psychology, optometry, orthoptics, and ophthalmology. Despite its broad use, considerable variation exists in how the PGT is implemented, particularly regarding stimulus parameters, participant characteristics, and scoring methods. Such variability introduces potential confounding factors that may obscure the psychological and neurological mechanisms underlying pattern-induced visual discomfort. METHODS: We analyzed PGT data from 184 neurotypical young adults (72 males and 112 female; mean age = 24.29 years, SD = 4.75) to examine methodological influences on reports of associated visual distortions (AVDs) and discomfort. Our main analyses utilized cumulative link mixed models and cluster analysis of intraindividual responses. RESULTS: Significant effects of trial progression and sex (biological; male/female) on subjective responses have been revealed, with the effect of sex not accounted for by migraine occurrence. Substantial overlap among color-related AVDs supported their consolidation into a single category. Response patterns have been consistent across participants, emphasizing the robustness of the effect of spatial frequencies in the PGT. CONCLUSIONS: These findings demonstrate that the PGT is sensitive to individual differences in visual discomfort, while also highlighting the impact of several confounding variables that require careful consideration. This underscores the importance of methodological standardization and supports the need for future research to refine scoring strategies, thereby enhancing the test's reliability and interpretability in both clinical and research contexts.