 To verify that participants adhere to the sleep protocol, they will be asked to keep a sleep diary and wear an activity monitor 24 hoursday. Participants will wear an actigraph GT3X on their wrist, which will serve to track their sleep duration, sleep timing, and physical activity. Two weeks prior to randomization and during the washout period, participants will also wear the actigraph watch and keep a sleep diary to verify sleep duration and sleep-wake schedule. In addition to achieving an average sleep of 7-9 hoursnight, by wrist actigraphy, participants will only be enrolled if they achieve 7 hours of sleep for at least 10 of the 14 nights of screening and have 4 nights with 6 hours of sleep. At the time of randomization, a urine pregnancy test and drug screen will be performed. Participants will be asked to abstain from caffeine and alcohol intake for 24 hours prior to the start. Between study phases, if participants have not returned to baseline sleep patterns within the 6 week washout period, an additional 2-4 week washout period will be provided. This washout length will ensure that women are in the same phase of their menstrual cycle at the start of each experimental phase. 