Paradoxes in Parkinson's disease and other movement disorders
Jha A., Brown P.
© Cambridge University Press 2011. The phenomenon of paradoxical facilitation has its greatest clinical impact in the field of movement disorders. Tens of thousands of people suffering from Parkinson's disease have spectacularly improved thanks to precisely placed surgical lesions or electrical stimulation deep in the centre of the brain. This chapter reports how this paradoxical benefit has driven science and medicine to unravel some of the secrets of one of the most complex circuits in the brain-the basal ganglia. We describe how careful anatomical studies of the basal ganglia have exposed their underlying circuitry, allowing scientists to ascribe function and capture dysfunction in disease. Against this background, we set a number of clinical paradoxes that challenge this model. These force us to take a leap in our conceptualization of the brain, considering it as a plastic network, perturbed by one or more disruptive signals in disease.