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Discover 14,441 clinical trials near Maryland. Find research studies in your area.
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NCT03733080
Background: Our goal is to gain insight into early human motor skill learning by carrying out online substudies using online crowd-sourcing tools. Objective: To learn more about motor behavior in a large group of people using motor tasks, and questions. Eligibility: Adults ages 18 and older based in the U.S. who speak English Design: Participants will be recruited from a crowd-sourcing website like Amazon Mechanical Turk. Participants will do online tasks. They can use their own computers anywhere with Internet access. They will not need to directly interact with researchers. Participants will be asked for general data, like their age and gender. No personally identifiable data will be collected. Participants will see a list of tasks on their computer screen. They will be able to choose tasks they wish to do. They will get a description of the experiment, how long it takes, and how much compensation they will get. Participants will complete on their screen a motor behavioral task, a cognitive task, and/or a questionnaire. For example, they may be asked to press sequences of numbers on the keyboard or move the mouse when a stimulus appears on the screen. Experiments may last up to 1 hour. Participants can complete as many experiments as they wish. They can quit at any point.
NCT03478865
Background: Age-related macular degeneration (AMD) is an eye disease. It is the leading cause of vision loss in people over 55 in the U.S. Changes in the eye can make it difficult for the eye to adjust to low light. This is known as dark adaptation. Identifying and watching the early to middle stages of AMD and changes in dark adaptation might help researchers develop new treatments to stop the disease before it becomes severe. Taking vitamin A might help improve vision in people with AMD. Objectives: To see if taking 16,000 IU of vitamin A per day improves vision in people with AMD. Also to improve understanding of AMD and associated dark adaptation. Eligibility: Adults ages 50 and older with AMD and normal liver function Design: Participants will be screened with: Medical and eye disease history Eye exam: The pupil will be dilated with eye drops. Pictures will be taken of the retina and the inside of the eye. Including the screening visit, participants will have at least 5 visits. They will be about once a month over 6 months. Visits include: Questions about eye problems in certain light Eye exam Blood and urine tests Dark adaptation protocol: Participants will sit at a machine in a dark room. They will look into the machine and push a button when they see a light. This lasts 20-30 minutes. Participants will take a vitamin A supplement by mouth once a day for 2 months. They will record when they take the pills in a diary.