Epworth Sleepiness Scale (ESS): The ESS is a paper-and-pencil test. In this test, a person records how likely she or he is to fall asleep in eight different situations: sitting and reading, watching TV, sitting inactive in a public place (such as at a theater or in a meeting), as a passenger in a car for an hour without a break, lying down to rest in the afternoon when circumstances permit, sitting and talking with someone, sitting quietly after a lunch without alcohol, and while driving a car, while stopped for a few minutes in traffic.
 
Food and Drug Administration (FDA): The FDA is a federal agency charged with ensuring that the food supply in the United States is safe and wholesome, that cosmetics are not harmful, and that medicines, medical devices, and radiation-emitting consumer products are safe and effective. 
 
Multiple Sleep Latency Test  (MSLT): The MSLT is used to measure how likely a person is to fall asleep. The test takes place over a seven-hour period during the day. Every two hours, for 20 minutes, the patient lies in a quiet dark room and is hooked up to a machine that measures brain waves, heart rate, muscle activity, and eye movements. This recording allows the doctor to see how quickly the patient falls asleep in this situation or if the patient falls asleep at all.
 
Narcolepsy: Narcolepsy is a  sleep disorder marked by sudden, uncontrollable urges to sleep that cause a person to fall asleep at inappropriate times. 
 
National Institutes of Health (NIH): The NIH is one of the world’s foremost medical research centers and the federal focal point for medical research in the United States. The NIH, comprising 27 separate Institutes and Centers, is one of eight health agencies of the Public Health Service that, in turn, is part of the U.S. Department of Health and Human Services.
 
Placebo: A placebo is a substance that appears to be identical to the treatment under study but that has no effects on the test subject. The placebo is given to members of the control group during experimental trials that test the effects of a drug or other substance.
 
Unified Parkinson Disease Rating Scale (UPDRS): The UPDRS is the most commonly used to tool to rate the symptoms of Parkinson's disease. This scale is intended to be used to follow the course of Parkinson’s disease in patients over a period of time. It is made up of three parts: (1) mentation (the process of thinking), behavior, and mood; (2) activities of daily living; and (3) motor symptoms.