Parkinson's disease causes symptoms.
Parkinson's disease . The symptoms generally come on slowly over time . Other symptoms include sensory , sleep , and emotional problems . The main motor symptoms are collectively called `` parkinsonism '' , or a `` parkinsonian syndrome '' . Diagnosis of typical cases is mainly based on symptoms , with tests such as neuroimaging being used to rule out other diseases . Diet and some forms of rehabilitation have shown some effectiveness at improving symptoms .