This is a 17 day study where participants will be evaluated by polysomnography on days one, two, three, sixteen and seventeen.. Polysomnographic measurements will include customary variables such as total sleep time, sleep efficiency, and sleep latency, as well as EMG measures of periodic and isolated muscle activity during sleep. Participants will be required to keep a detailed sleep log of their self reported sleep characteristics across the entire 17 study nights. Outcomes will include measures of both nocturnal sleep and waking motor function. Assessments of motor function will be made the morning immediately following Nights 3 and 17 in order to test for improvement related to improved sleep. On the morning following Night 17, participants are provided with a one-week supply of valerian in an Open Label extension. Participants are provided an additional Sleep Log for this week and asked to return the Sleep Log when they complete the Open Label phase.