1. Cognition among individuals along a spectrum of increased risk for Parkinson’s disease Chahine, Lana M.; Urbe, Liz; Caspell-Garcia, Chelsea; Aarsland, Dag; Alcalay, Roy Nissim; Barone, Paolo; Burn, David; Espay, Alberto J.; Hamilton, Jamie L.; Hawkins, Keith A.; Lasch, Shirley; Leverenz, James B.; Litvan, Irene; Richard, Irene; Siderowf, Andrew; Coffey, Christopher S.; Simuni, Tanya; Weintraub, Daniel; Parkinson’s Progression Markers Initiative 2018 Articles CognitionParkinson's disease--PatientsDiseases--Risk factorsCognitive neuroscienceNeurology