The purpose of this study is to improve understanding of neurological conditions. Patients participating in this study will continue receiving medical care, routine laboratory tests, and diagnostics tests (X-rays, CT-scans, and nuclear imaging), from their primary care physician. Doctors at the NIH plan to follow these patients and offer advice and assistance to their primary care physicians.

The objective of this protocol is to provide diagnosis and follow Experimental Therapeutics Branch (ETB) patients not currently entered on another research protocol. No investigational treatments will be administered on this protocol, and the NIH physicians will be playing largely a consultative role to the patient's primary physician.

INCLUSION CRITERIA:

Patients may be included on this protocol if they have an identifiable neurological disorder or represent a diagnostic puzzle. These disorders would include patients with Parkinson's disease, Alzheimer's disease, multiple system atrophy, progressive supranuclear palsy, restless legs syndrome, other cognitive and movement disorders, and diagnostic puzzles.

Patients 18-90 years of age, inclusive, are eligible.