Study participation involves several clinic visits.
Clinic visits involve having height and weight measured and completing questionnaires and a semi-structured interview. Some studies involve undergoing an MRI scan while viewing different pictures. Some studies involve keeping sleep diaries and responding to text messages that include questionnaires and cognitive tasks at intervals throughout the day. Some studies involve clinic visits over a 2-year period. Participants without a smartphone will be loaned study-provided smartphones for the duration of their participation. Participants will be compensated for each study visit and for study activities in exchange for their time and effort.