I, too, would be interested in a more detailed explanation of this difference. I was referred to the www.pallidotomy.com site, which said that type B PD (the more aggressive kind) is characterized by akinetic symptoms. If I remember correctly, this is the lack of movement. What exactly is meant by this? Is bradykinesia a type of akinesia?? (I am personally interested because my mother doesn't have much of a tremor, and when she does, it doesn't seem better when active, as classic PD tremors are. Also, she exhibits slowness and other symptoms which, if I had to characterize them, would fall on the side of absence of movement rather than too much movement.) As always, thanks. Debbie White [log in to unmask] > > >From time to time there are references to Types A & B PD on the List. > Type B seems to be a PD condition without tremor that progresses > more rapidly? Are there really two types of PD? Can anyone clarify > this mystery? Thanks in advance. Ann Gibbons