Martino JT, et al. - This study was conducted to examine the effect of light therapy (LT) on insomnia and nocturnal movement in Parkinson’s disease (PD). Findings revealed that the efficacy of LT in alleviating these sleep-related conditions was not compromised by time since diagnosis or age of the patient. For treating sleep disorders in PD, long-term application of non-invasive techniques like LT was found to be of value.