Neurology Research

Volume renderings of the globus pallidus (PGi: green; GPe: Blue), red nucleus (red), subthalamic nucleus (yellow) and substantia nigra (light blue). Note that the light purple structures which appears to lie under the green GPi's are, in fact, parts of the blue GPe's; they appear to be purple as a result of being visualized through the overlying brownish-yellow semitransparent thalami. MRI images courtesy of Dr. Noam Harel's team at the Center for Magnetic Resonance Research, University of Minnesota.

The University of Minnesota (Department of Neurology) is one of five sites participating in BioFind, a two-year observational clinical study designed to discover and verify biomarkers of Parkinson's disease. Biofind is funded by the Michael J. Fox Foundation for Parkinson's Research and the NIH.

“Freezing of gait” is defined as a temporary involuntary inability to move. “About 70 percent of people with advanced Parkinson's disease will experience freezing,” says Colum MacKinnon, Ph.D., a movement disorders researcher and an Assistant Professor of Neurology in the University of Minnesota Medical School. “If you ask them what their number-one problem with quality of life is, they'll tell you it's issues with their mobility.”

The freezing phenomenon is not well understood. Nor is it understood why certain actions or “cues”, like a tap on the shoulder or a countdown (3-2-1-go), can “unfreeze” people who have Parkinson's disease.

MacKinnon and his colleagues are investigating the most effective ways to use cues and how clinicians and caregivers should present cues to most reliably overcome freezing episodes. A subsequent series of experiments will examine the brain physiology behind freezing and why cueing works. The group's current research involves measuring movement with high-speed cameras and recording the muscle and brain activity of people with Parkinson's disease as they prepare to move and then when they actually move.