title: Now you see it; now you don't.
authors.affiliation: Division of Cardiology, Feinberg School of Medicine, Northwestern University, Chicago, Ill, USA. normanwang@hotmail.com
authors.forename: Norman C
authors.initials: NC
authors.lastname: Wang
mesh_terms: D000369:Aged, 80 and over; D016477:Artifacts; D004562:Electrocardiography; D006801:Humans; D008297:Male; D014202:Tremor