title: A functional magnetic resonance imaging study of pathophysiological changes responsible for mirror movements in Parkinson's disease.
abstract: Mirror movements correspond to involuntary movements observed in the limb contralateral to the one performing voluntary movement. They can be observed in Parkinson's disease (PD) but their pathophysiology remains unclear. The present study aims at identifying their neural correlates in PD using functional magnetic resonance imaging. Ten control subjects and 14-off drug patients with asymmetrical right-sided PD were included (8 with left-sided mirror movements during right-hand movements, and 6 without mirror movements). Between-group comparisons of BOLD signal were performed during right-hand movements and at rest (p<0.005 uncorrected). The comparison between PD patients with and without mirror movements showed that mirror movements were associated with an overactivation of the insula, precuneus/posterior cingulate cortex bilaterally and of the left inferior frontal cortex and with a deactivation of the right dorsolateral prefrontal cortex, medial prefrontal cortex, and pre-supplementary motor area and occipital cortex. These data suggest that mirror movements in Parkinson's disease are promoted by: 1- a deactivation of the non-mirroring inhibitory network (dorsolateral prefrontal cortex, pre-supplementary motor area); 2- an overactivation of prokinetic areas (notably the insula). The concomitant overactivation of a proactive inhibitory network (including the posterior cingulate cortex and precuneus) could reflect a compensatory inhibition of mirror movements.
authors.affiliation: Université de Lyon, Faculté de Médecine Lyon Sud Charles Mérieux, Lyon, France.
authors.forename: Alice
authors.initials: A
authors.lastname: Poisson
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Ballanger
authors.forename: Elise
authors.initials: E
authors.lastname: Metereau
authors.forename: Jérome
authors.initials: J
authors.lastname: Redouté
authors.forename: Danielle
authors.initials: D
authors.lastname: Ibarolla
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Comte
authors.forename: Hélène Gervais
authors.initials: HG
authors.lastname: Bernard
authors.forename: Marie
authors.initials: M
authors.lastname: Vidailhet
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Broussolle
authors.forename: Stéphane
authors.initials: S
authors.lastname: Thobois
mesh_terms: D000368:Aged; D020820:Dyskinesias / Q000150:complications / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology*