ABSTRACT
INTRODUCTION In the last decades, technological innovations have provided a better understanding of the mechanisms underlying neurological disorders. Magnetic resonance imaging (MRI) has evolved into functional MRI, with the ability to measure regional cerebral function with good temporal resolution. Increases in spatial resolution of positron emission tomography (PET) and single-photon emission computed tomography (SPECT), associated with the development of new radiotracers, have also allowed novel approaches to the study of disease. The impact of such advances is particularly pronounced in the fi elds of movement disorders and epilepsy. The investigation of Parkinson’s disease (PD) and dystonia has benefi ted substantially from this advanced and more widely available technology. In PD, functional imaging is useful in detecting dopaminergic cell loss and changes in cerebral metabolic rates at rest or during the performance of behavioral or motor tasks. As for the various forms of dystonia, imaging has corroborated what was suggested in clinical and pathologic investigations: instead of a single pathologic focus, dystonia is the consequence of dysfunction in the cortico-subcortical networks of sensorimotor control, in which the basal ganglia are only one of the players.
