Bicycling with Parkinson

The April 1, 2010 New England Journal of Medicine includes an "Image in clinical medicine" that was highlighted in today's New York Times. It shows a Parkinson disease patient with severe freezing and festination, as well as the classic stooped posture and bilateral upper extremity tremor. His appearance is remarkably similar to the famous drawing in Gowers' textbook from 1886. His symptoms melt away when he rides a bike. There is a video available with the article.

Variations on this phenomenon have been recognized in PD for a while and are usually explained by the fact that the patient is accessing motor programs quite different from the automatic one involved with walking.