Parkinson's and Alzheimer's: new tools, new attitudes in patient care.

In 1946, the differential diagnosis of cognitive failure resided in the hands of psychiatrists. Not until the late 1960s was permanent doubt cast on the arteriosclerotic origins of dementia. Neuro-diagnostic studies 50 years ago were limited to skull x-rays. Many neurologic signs that would now be considered indicative of Parkinson's disease (PD) were thought in 1946 to typify old age. The diagnosis of PD was made on clinical grounds, and in that regard little has changed. For treatment of PD, textbooks then had little to offer, compared with the wide range of drug therapies available today. Unknown in the mid-1940s, the molecular biology of DNA now allows practitioners a glimpse at the highly complex and multifactorial origins of Alzheimer's disease.