Specific neocerebellar activation during out-of-phase bimanual movements.
We used fMRI to study cerebellar activation during index finger-thumb opposition of the right hand and index finger-thumb opposition of both hands in in-phase and out-of-phase modes. The right hand movement activates the contralateral anterior lobe of the cerebellum. During bimanual in-phase movements, this activity pattern becomes bilateral. More interestingly, bilateral out-of-phase movements recruit the cerebellar posterior lobe VIII, which likely corresponds to the second homunculus. As out-of-phase movements differ from the in-phase movements only by their temporal complexity and their attentional awareness, this study demonstrates the preferential involvement of the cerebellar second homunculus in the control of complex movements.
Habas
C
C
Laboratoire de Neurobiologie du Cervelet, Faculté de Médecine Pitié-Salpêtrière, 91 Bd. de l'Hôpital, 75013 Paris, France. christophe.habas@libertysurf.fr
Axelrad
H
H
Nguyen
T H
TH
Cabanis
E-A
EA
D000328:Adult; D001288:Attention / Q000502:physiology; D001931:Brain Mapping; D002531:Cerebellum / Q000033:anatomy & histology / Q000502:physiology*; D005246:Feedback / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology*; D006225:Hand / Q000294:innervation* / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D011434:Proprioception / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D013997:Time Factors; D013998:Time Perception / Q000502:physiology