Many individuals with Parkinson’s disease are able to recall losing their sense of smell well before the onset of more commonly recognized symptoms such as tremors, impaired dexterity, speech problems, memory loss and decreased cognitive ability.

To determine if a fading sense of smell may signal Parkinson’s, researchers at Northwestern Memorial Hospital and Northwestern University’s Feinberg School of Medicine are participating in a national study to examine the correlation and ascertain whether smell loss presents a tool for early detection of the disease and an opportunity to delay or ultimately prevent more troublesome symptoms.

northwestern.edu/newscenter/stories/2009/01/parkinsonstest.html