Dissociation in the neural control of single-joint and multi-joint movements in the thalamic ataxia syndrome.
We report a patient presenting with a right thalamic ataxia syndrome following a hemorrhage located in the left lateral and posterior thalamus. We investigated the fast goal-directed movements of the wrists (single-joint movements) and the fast pointing movements in the upper limbs (multi-joint movements). On the right side, single-joint movements were markedly hypermetric and characterized by an asymmetry in kinematics, an abnormality of ballistic movements which is considered to be a fundamental cerebellar disorder. By contrast, rapid multi-joint movements were only very slightly impaired. These results suggest that ballistic movements of the wrist are under the strong influence of the cerebello-thalamo-cortical pathway, while rapid pointing multi-joint movements in upper limb are mostly influenced by another pathway emerging from the lateral cerebellum, possibly the dentato-rubral or the dentato-reticular projections in the brainstem. The roles of these neuroanatomical pathways in the control of fast single-joint and multi-joint movements are discussed.
van Blercom
N
N
Service de Neurologie, Hôpital Erasme, Brussels, Belgium.
Manto
M
M
Jacquy
J
J
Hildebrand
J
J
D001259:Ataxia / Q000503:physiopathology*; D002524:Cerebellar Ataxia / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology; D013577:Syndrome; D013786:Thalamic Diseases / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed