title: Brain plasticity in the motor network is correlated with disease progression in amyotrophic lateral sclerosis.
abstract: OBJECTIVE
  To test the influence of functional cerebral reorganization in amyotrophic lateral sclerosis (ALS) on disease progression.
  
  
  METHODS
  Nineteen predominantly right-handed ALS patients and 21 controls underwent clinical evaluation, functional Magnetic Resonance Imaging (fMRI), and diffusion tensor imaging. Patients were clinically re-evaluated 1 year later and followed until death. For fMRI, subjects executed and imagined a simple hand-motor task. Between-group comparisons were performed, and correlations were searched with motor deficit arm Medical Research Council (MRC) score, disease progression ALS Functional Rating Scale (ALSFRS), and survival time.
  
  
  RESULTS
  By the MRC score, the hand strength was lowered by 12% in the ALS group predominating on the right side in accordance with an abnormal fractional anisotropy (FA) limited to the left corticospinal tract (37.3% reduction vs. controls P < 0.01). Compared to controls, patients displayed overactivations in the controlateral parietal (P < 0.004) and somatosensory (P < 0.004) cortex and in the ipsilateral parietal (P < 0.01) and somatosensory (P < 0.01) cortex to right-hand movement. Movement imagination gave similar results while no difference occurred with left-hand tasks. Stepwise regression analysis corrected for multiple comparisons showed that controlateral parietal activity was inversely correlated with disease progression (R(2) = 0.43, P = 0.001) and ipsilateral somatosensory activations with the severity of the right-arm deficit (R(2) = 0.48, P = 0.001).
  
  
  CONCLUSIONS
  Cortical Blood Oxygen Level Dependent (BOLD) signal changes occur in the brain of ALS patients during a simple hand-motor task when the motor deficit is still moderate. It is correlated with the rate of disease progression suggesting that brain functional rearrangement in ALS may have prognostic implications.
authors.affiliation: INSERM U1028, Centre de Recherche en Neurosciences de Lyon, Université de Lyon, F-42023, Saint-Etienne, France; Service de Neurologie, Centre SLA, Centre Hospitalier Universitaire, Saint-Etienne, France.
authors.forename: Aurélia
authors.initials: A
authors.lastname: Poujois
authors.forename: Fabien C
authors.initials: FC
authors.lastname: Schneider
authors.forename: Isabelle
authors.initials: I
authors.lastname: Faillenot
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Camdessanché
authors.forename: Nadia
authors.initials: N
authors.lastname: Vandenberghe
authors.forename: Catherine
authors.initials: C
authors.lastname: Thomas-Antérion
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Antoine
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000503:physiopathology*; D016880:Anisotropy; D001132:Arm / Q000294:innervation; D001931:Brain Mapping; D002560:Cerebrovascular Circulation; D056324:Diffusion Tensor Imaging; D018450:Disease Progression; D005260:Female; D006225:Hand / Q000294:innervation; D018737:Hand Strength; D006801:Humans; D007092:Imagination; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D009415:Nerve Net / Q000503:physiopathology*; D009473:Neuronal Plasticity; D010100:Oxygen / Q000097:blood; D010296:Parietal Lobe / Q000503:physiopathology*; D011712:Pyramidal Tracts / Q000503:physiopathology*; D012720:Severity of Illness Index; D013003:Somatosensory Cortex / Q000503:physiopathology*
chemical_list: D010100:Oxygen