Due to the COVID-19 safety precautions, we are limiting access to the MRI technologist, researcher/s (two or less), and the participant. If the participant is a minor, one parent may accompany the participant into the MRI Lab and remain seated in the lab waiting area while the scan is completed. If there is a visitor, (not a participant), who the PI or researcher would like to observe the scan, prior arrangement with the MRI Technologist, (Susan Tozzi at stozzi@gmu.edu), in advance of the visit is required.