The neuroimaging evidence of brain abnormalities in functional movement disorders

Abstract

Neuroimaging has been pivotal in identifying and reframing our understanding of functional movement disorders. If accessible, it compensates for the limitations of the clinical exam and is especially useful where there is overlap of functional symptoms with classical presentations of disease. Imaging in functional movement disorders has increasingly identified structural and functional abnormalities that implicate hypoactivation of the cortical and subcortical motor pathways and increased modulation by the limbic system. Neurobiological theories suggest an impaired sense of agency, faulty top-down regulation of motor movement and abnormal emotional processing in these individuals. This framework challenges our traditional understanding of functional movement disorders as distinct from the deceptive term of 'organic' diseases and proposes that these conditions are not considered as mutually exclusive. This update summarizes the literature to date and explores the role of imaging in the diagnosis of functional movement disorders and in detecting its underlying molecular network.

Keywords: MRI; PET; SPECT; functional movement disorders; imaging.