Spatial disorientation as an early symptom of Parkinson's disease.

In 44 consecutive outpatients with idiopathic Parkinson's disease (PD) without levodopa substitution therapy, we tested spatial orientation. Spatial orientation was impaired on the rod orientation test in 43 patients, on the line orientation test in 7 patients, and on the facial recognition test in 17 patients. There was no correlation between severity of spatial disorientation and age, length of illness, verbal WAIS score, or severity of PD. Impairment of spatial orientation is part of PD even in mild cases.