par Sauvage, Chloé ;Jissendi Tchofo, Patrice ;Manto, Mario ;Habas, Christophe; [et al.]
Référence Journal of neuroradiology, 42, 2, page (115-125)
Publication Publié, 2013-10-01
Article révisé par les pairs
Résumé : We investigated the cerebral networks involved in execution and mental imageryof sequential movements of the left foot, both performed at slow and fast speed. Twelvevolunteers were scanned with a 3T MRI during execution and imagination of a sequence ofankle movements. Overt movement execution and motor imagery shared a common networkincluding the premotor, parietal and cingulate cortices, the striatum and the cerebellum.Motor imagery recruited specifically the prefrontal cortex, whereas motor execution recruitedspecifically the sensorimotor cortex. We also found that slow movements specifically recruitedfrontopolar and right dorsomedian prefrontal areas bilaterally, during both execution and men-tal imagery, whereas fast movements strongly activated the sensorimotor cerebral cortex.Finally, we noted that anterior vermis, lobules VI/VII and VIII of the cerebellum were specifi-cally activated during fast movements, both in imagination and execution. We show that theselection of the neural networks underlying voluntary movement of the foot is depending on thespeed strategy and is sensitive to execution versus imagery. Moreover, to the light of surprisingrecent findings in monkeys showing that the vermis should no longer be considered as entirelyisolated from the cerebral cortex (Coffman et al., 2011), we suggest that the anterior ver-mis contributes to computational aspects of fast commands, whereas more lateral cerebellarsuperior lobe and lobule VIII would regulate patterning and sequencing of submovements in conjunction with movement rate. We also suggest that execution of overt slow movements,which strongly involves prefrontal executive cortex as during motor mental imagery, is associ-ated with conscious mental representation of the ongoing movements.

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