Balance and the brain


Mark Carpenter, Associate Professor, Canada Research Chair, School of Kinesiology, University of British Columbia
Porridge for Parkinson's (Toronto) Pilot Project Grant: $45,000

Scientific title: A novel fMRI approach to investigating the pathophysiology of postural instability in Parkinson's disease

Balance problems that result in falls are a major problem for people with Parkinson's disease – a problem unresolved by medication or surgery that relieves other motor symptoms.

At the University of British Columbia, neuroscientist Mark Carpenter investigates the causes of balance instability and falls, as well as why this symptom of Parkinson's doesn't respond to current treatments.
Carpenter wonders whether balance is controlled by other areas of the brain than the regions that control other motor functions. He's also considering the possibility that people with Parkinson's disease are unable to detect where their limbs are in space, a phenomenon called proprioception. Using functional Magnetic Resonance Imaging (fMRI) to scan the brains of people with Parkinson's disease while they perform a balancing task, Carpenter will try to determine what structures in the brain control balance and where they are located.

“If we can understand which areas of the brain are controlling balance, and if there's evidence that Parkinson's disease affects those areas, then we have new targets for treatment or new ways of trying to understand the causes of falls,” Carpenter says.

Carpenter and his team are developing a balance simulator that people can control while they are lying in the brain imaging machine, by balancing an inverted pendulum with their ankles. The simulator will engage some of the same muscles and feedback systems the brain uses while balancing, allowing the researchers to capture more accurate images of the regions in the brain that are involved in balance. Comparing the images captured during the balance task, with images from non-balance tasks, like returning their ankle to a neutral position, helps determine how proprioception may contribute to the balance problems in people with Parkinson’s.

Ultimately, by understanding what areas of the brain are directly involved in balance, Carpenter hopes to open up a new treatment avenue that targets these additional regions of the brain, to reduce the balance problems and falls that people with Parkinson's disease experience.