In Reply We read with interest the Letter to the Editor by Li and Tian. Their letter centers on the potential novel mechanism of action of light therapy in Parkinson disease (PD). Specifically, they highlight the possibility that light therapy may promote dopamine release by stimulating cells within the retina, which translates to improvements of PD symptoms. We agree that this is a sound scientific hypothesis based on the current understanding of the intricate relationship between the retinal dopaminergic function in PD and the circadian system.
Aleksandar Videnovic, Elizabeth B. Klerman, Phyllis C. Zee. Light Therapy Promoting Dopamine Release by Stimulating Retina in Parkinson Disease—Reply. JAMA Neurol. 2017;74(10):1268–1269. doi:10.1001/jamaneurol.2017.1909