title: Relationship between event-related desynchronization and cortical excitability in healthy subjects and stroke patients.
abstract: OBJECTIVE
  Relation between cortical excitability and magnitudes of event-related dysynchronizaton (ERD) has not been clarified. This study was investigated that relationshp between cortical excitability and ERD magnitudes in healthy subjects and stroke patients.
  
  
  METHODS
  Ten healthy subjects and four patients with stroke participated in this study. EEGs were recorded over the sensorimotor cortex (left hemisphere in healthy subjects; damaged hemisphere in stroke subjects) to calculate ERD during motor imagery,. Motor-evoked potential (MEP) induced by single-pulse transcranial magnetic stimulation over the primary motor cortex was recorded from the first dorsal interosseus (FDI) muscle at ERD magnitudes of 10% and 30%.
  
  
  RESULTS
  MEP significantly increased at 10% and 30% ERD (p<0.01) than that during rest in healthy subjects. The 30% ERD condition showed significantly higher MEP than that at 10% ERD (p<0.05). In stroke patients, MEP increased with ERD induced by motor imagery, but the change of MEP to ERD amplitude was critically different among the subject.
  
  
  CONCLUSIONS
  ERD magnitude corresponds to corticospinal excitability increases in healthy subjects and patients with hemiplegic stroke. BCI based on motor imagery-induced ERD may be a potential rehabilitation strategy for patients with hemiplegic stroke.
authors: Department of Rehabilitation Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan. ko_ao417@ybb.ne.jp.
authors: Koji
authors: K
authors: Aono
authors: Shotaro
authors: S
authors: Miyashita
authors: Yosuke
authors: Y
authors: Fujiwara
authors: Mitsuhiko
authors: M
authors: Kodama
authors: Kozo
authors: K
authors: Hanayama
authors: Yoshihisa
authors: Y
authors: Masakado
authors: Junichi
authors: J
authors: Ushiba
mesh_terms: D000328:Adult; D000368:Aged; D003344:Cortical Synchronization / Q000502:physiology*; D004569:Electroencephalography; D005071:Evoked Potentials; D019054:Evoked Potentials, Motor; D005260:Female; D006801:Humans; D007092:Imagination / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology*; D020521:Stroke / Q000503:physiopathology*; D000071939:Stroke Rehabilitation; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult