Migraine is a disorder that ranges in clinical severity from milder episodic migraine (EM) to severe chronic migraine (CM)--a debilitating condition for people with migraine. Prior studies have demonstrated that migraineurs experience photophobia (sensitivity to light)--and have lower sensory thresholds compared to healthy controls. Headache day frequency is also shown to have short-term variability between months for migraineurs when followed longitudinally. My project will utilize existing data from the lab of Drs Cortez and Brennan, which examined sensory and pupillary function in migraine participants. The parent project collected longitudinal data on the progression of migraine in patients and measured sensory biomarkers, such as sensitivity to light. My research effort will use the same data to divide migraine participants into two groups: those with minimal light sensitivity, and those with an abnormal threshold of light sensitivity. Pupillary light reflex (PLR) data between the two groups was compared between groups. Additionally, the migraine outcomes of the photophobic/severe migraine group over the course of a 6-month period were analyzed to explore trends in the trajectory of severely photophobic migraine participants. I hypothesize that the photophobic/severe migraine group will have pupillometry data showing an altered pupillary response compared to the control group, and baseline photophobia will correlate with worsened migraine outcomes over the 6-month period. My research will provide additional evidence that photophobia in migraine is linked to worse migraine outcomes over time, and can be a useful prognostic sensory biomarker for patients that may develop CM from EM.