title: Resting state eyes-closed cortical rhythms in patients with locked-in-syndrome: an EEG study.
abstract: OBJECTIVE
  Locked-in syndrome (LIS) is a state of complete paralysis, except for ocular movements, which results from ventral brainstem lesions. Patients typically are fully conscious. Here we tested the hypothesis that electroencephalographic (EEG) rhythms are abnormal in LIS patients, possibly due to an impaired neural synchronization between brainstem and cerebral cortex.
  
  
  METHODS
  Resting state eyes-closed EEG data were recorded in 13 LIS subjects and 15 cognitively normal control subjects. With reference to the individual alpha frequency (IAF), the bands of interest were delta (IAF-8 to IAF-6Hz), theta (IAF-6 to IAF-4Hz), alpha 1 (IAF-4 to IAF-2Hz), alpha 2 (IAF-2 to IAFHz), and alpha 3 (IAF to IAF+2Hz). Furthermore, beta 1 (13-20Hz) and beta 2 (20-30Hz) bands were also considered. Cortical EEG sources were estimated by low-resolution electromagnetic tomography (LORETA).
  
  
  RESULTS
  The power of alpha 2 and alpha 3 sources in all regions was lower in patients with LIS compared to controls. The power of delta sources in central, parietal, occipital and temporal regions was higher in patients with LIS compared to controls.
  
  
  CONCLUSIONS
  These results suggest that cortical sources of resting state eyes-closed alpha and delta rhythms are abnormal in LIS patients.
  
  
  CONCLUSIONS
  LIS is accompanied by a functional impairment of cortical neuronal synchronization mechanisms in the resting state condition.
authors.affiliation: Department of Biomedical Sciences, University of Foggia, Italy; Department of Imaging, SAN RAFFAELE Cassino, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Babiloni
authors.forename: Francesca
authors.initials: F
authors.lastname: Pistoia
authors.forename: Marco
authors.initials: M
authors.lastname: Sarà
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Vecchio
authors.forename: Paola
authors.initials: P
authors.lastname: Buffo
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Conson
authors.forename: Paolo
authors.initials: P
authors.lastname: Onorati
authors.forename: Giorgio
authors.initials: G
authors.lastname: Albertini
authors.forename: Paolo Maria
authors.initials: PM
authors.lastname: Rossini
mesh_terms: D000328:Adult; D000368:Aged; D000513:Alpha Rhythm / Q000379:methods; D001931:Brain Mapping / Q000379:methods; D001933:Brain Stem / Q000503:physiopathology; D002540:Cerebral Cortex / Q000502:physiology*; D003700:Delta Rhythm / Q000379:methods; D004569:Electroencephalography / Q000379:methods*; D005123:Eye; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011782:Quadriplegia / Q000175:diagnosis / Q000503:physiopathology*; D012146:Rest / Q000502:physiology*; D012683:Sensory Deprivation / Q000502:physiology*