Here's my observstion and experience: both PD and the medication can cause personality changes. They can be very subtle and incremental...sometimes it may start as a mild deviation or grown from one's original character attitude to become noticeable behaviorbsession or compulsive ...whatever you named it. They are consciously "unwanted" behavior, differences in the degree of control.

There Is not much help from neurologist as it proves to be too complex for them.