Parkinson’s Disease Award funded by Guildford Inner Wheel, Valerie Gibson, Ami Olian Memorial Fund and the Estates of Grace Jeanie Admans, Esther Hennessy, Leslie Keller, Helynne Annette Hoban and Bruce Smith
Brain adaptation underlying remarkable improvement in symptoms of Parkinson’s disease after effective surgical and drug treatment.
Dr Stephen Tisch
Department of Neurology St Vincent’s Hospital and University of New South Wales
Parkinson’s disease is a progressive movement disorder which causes tremors, stiffness, slowness and difficulty walking. It affects 3 % of people over the age of 55 in Sydney. There is no cure for Parkinson’s disease but oral medications which replace dopamine in the brain can help the symptoms. As the disease progresses the response to medications becomes uneven and patients may fluctuate between good and bad phases and develop involuntary movements. It is believed that fluctuations and involuntary movements develop because of abnormal rewiring (plasticity) within brain motor areas in response to the medications. Some newer treatments can help once oral medications fail. These include deep brain stimulation (DBS) surgery or continuous infusions of a medication called apomorphine. These treatments reduce the fluctuations and involuntary movements, providing more stable improvement. In some patients the improvement can be dramatic. This study will investigate how these treatments alter brain function in order to achieve the beneficial effects. The study will assess patients with Parkinson’s disease before and after DBS surgery or apomorphine infusion using electrical tests of brain function. Some milder Parkinson’s patients without fluctuations or involuntary movements as well as healthy control group will also be studied for comparison. It is predicted that abnormal patterns of brain function will be present in patients with fluctuations and involuntary movements. These abnormal patterns may readapt to a more normal configuration after treatment with DBS or apomorphine infusion corresponding to improvement in the patients’ condition. The overall aim of the study is to gain a better understanding of how these treatments work and the role of brain plasticity in this process. This study will further the understanding of Parkinson’s disease and may help guide improved future treatments or tests to help predict responsiveness to therapeutic interventions.