Systemic lupus erythematosus (SLE) is an autoimmune disorder affecting multiple organ systems. In this project, we examine the negative impact of sunlight exposure on inhibition task performance and physical and cognitive symptoms in participants with SLE. This study is a continuation of a longitudinal experiment we completed in summer of 2018. In addition, we compare variations in SLE participants’ cognitive performance to those of healthy controls without cognitive impairment over a ten-week time period. The longitudinal design of this study allows us to further investigate fluctuations in cognitive performance and physical and cognitive symptom reporting by looking at the variations in sunlight exposure over time. Additionally, we found seasonal differences between data collected during summer and winter months.