title: Cortical activation and inter-hemispheric sensorimotor coherence in individuals with arm dystonia due to childhood stroke.
abstract: OBJECTIVE
  Dystonia is a disabling motor disorder often without effective therapies. To better understand the genesis of dystonia after childhood stroke, we analyzed electroencephalographic (EEG) recordings in this population.
  
  
  METHODS
  Resting spectral power of EEG signals over bilateral sensorimotor cortices (Powrest), resting inter-hemispheric sensorimotor coherence (Cohrest), and task-related changes in power (TRPow) and coherence (TRCoh) during wrist extension were analyzed in individuals with dystonia (age 20±3years) and healthy volunteers (age 17±5years).
  
  
  RESULTS
  Ipsilesional TRPow decrease was significantly lower in patients than controls during the more affected wrist task. Force deficits of the affected wrist correlated with reduced alpha TRPow decrease on the ipsilesional and not the contralesional hemisphere. Cohrest was significantly lower in patients than controls, and correlated with more severe dystonia and poorer hand function. Powrest and TRCoh were similar between groups.
  
  
  CONCLUSIONS
  The association between weakness and cortical activation during wrist extension highlights the importance of ipsilesional sensorimotor activation on function. Reduction of Cohrest in patients reflects a loss of inter-hemispheric connectivity that may result from structural changes and neuroplasticity, potentially contributing to the development of dystonia.
  
  
  CONCLUSIONS
  Cortical and motor dysfunction are correlated in patients with childhood stroke and may in part explain the genesis of dystonia.
authors.affiliation: Biomedical Engineering Department, The Catholic University of America, USA; Rehabilitation Medicine Department, National Institutes of Health Clinical Center, USA; National Institute of Neurological Disorders and Stroke, National Institutes of Health, USA.
authors.forename: Sahana N
authors.initials: SN
authors.lastname: Kukke
authors.affiliation: Rehabilitation Medicine Department, National Institutes of Health Clinical Center, USA.
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: de Campos
authors.affiliation: Rehabilitation Medicine Department, National Institutes of Health Clinical Center, USA.
authors.forename: Diane
authors.initials: D
authors.lastname: Damiano
authors.affiliation: Rehabilitation Medicine Department, National Institutes of Health Clinical Center, USA; Mount Washington Pediatric Hospital, USA.
authors.forename: Katharine E
authors.initials: KE
authors.lastname: Alter
authors.affiliation: Radiology Department, National Institutes of Health Clinical Center, USA.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Patronas
authors.affiliation: National Institute of Neurological Disorders and Stroke, National Institutes of Health, USA. Electronic address: hallettm@ninds.nih.gov.
authors.forename: Mark
authors.initials: M
authors.lastname: Hallett
mesh_terms: D000293:Adolescent; D001132:Arm / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000503:physiopathology*; D002648:Child; D020821:Dystonic Disorders / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology; D009434:Neural Pathways / Q000503:physiopathology; D011597:Psychomotor Performance / Q000502:physiology; D020521:Stroke / Q000150:complications / Q000503:physiopathology*; D055815:Young Adult
keywords: Cerebral palsy; Childhood stroke; Coherence; Cortical activation; Dystonia; Electroencephalography