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Normal functional imaging of the basal ganglia Volume 4, supplément 3, Supplement 3, December 2002


   
   Figure 1. Schematic representation of fronto-striatal projections. Abbreviations: CN, caudate nucleus; FEF, frontal eye field; MC, motor cortex; OF, orbito-frontal cortex; PF, prefrontal cortex; PM, premotor cortex; Pu, putamen, T, thalamus; VS, ventral striatum.



   
   Figure 2. Cortico-subcortical activation during simple hand movement (3T fMRI). Activation of the sensorimotor compartment of the putamen during flexion/extension of the fingers of the right hand. The putamen is activated bilaterally along with the contralateral sensorimotor cortex (SMC), the supplementary motor area (SMA), the ventrolateral thalamus (T), bilateral secondary somatosensory area (SII) and ipsilateral cerebellum (CE). Right is left.



   
   Figure 3. Somatotopic representation of the toes, fingers, lips, and eyes in the left striatum (adapted from [73]) (1.5T fMRI). Left and middle: Within the left putamen, pixels activated during self-paced flexion/extension of the toes were located in the dorsal part of the structure (red), pixels activated during lip contraction were located more ventrally and medially (blue), and pixels activated during flexion/extension of the fingers were located in between (yellow). There is a moderate overlap between territories (green). Right: activation during horizontal self-paced saccadic eye movements (orange). Abbreviations: Ant, anterior; CN, caudate nucleus; Post, posterior; Pu, putamen.



   
   Figure 4. fMRI activation maps during execution, preparation, selection of the side of button pressing, and during imagination of hand movements. Upper row: superior view of the cortex, lower row: axial slice at the level of the basal ganglia. When subjects executed the movement (corresponding to pressing a button, left column), activation was observed in the sensorimotor circuit including the sensorimotor cortex (SMC), the posterior part of the SMA (SMA) and the posterior part of the putamen (Pu post). When subjects prepared to press the button (middle left), activation was found in the contralateral motor and adjacent premotor cortex (MC/PM), the preSMA, and the anterior part of the putamen (Pu ant). When subjects selected which side they were going to press the button (middle right), activation was found in the prefrontal (PF) and associative parietal areas (Par), and the caudate nucleus (CN) (adapted from [61]). Similarly, when subjects imagined simple (simultaneous flexion/extension of the fingers), or complex (selective flexion/extension of the index and the little finger right) hand movements, activation was found in the premotor, prefrontal, and associative parietal areas, and in the anterior putamen and caudate nucleus (adapted from [48]). Lower row: right is right.