title: Global, regional, and local measures of complexity of multichannel electroencephalography in acute, neuroleptic-naive, first-break schizophrenics.
abstract: BACKGROUND
  Schizophrenic symptoms commonly are felt to indicate a loosened coordination, i.e. a decreased connectivity of brain processes.
  
  
  METHODS
  To address this hypothesis directly, global and regional multichannel electroencephalographic (EEG) complexities (omega complexity and dimensional complexity) and single channel EEG dimensional complexities were calculated from 19-channel EEG data from 9 neuroleptic-naive, first-break, acute schizophrenics and 9 age- and sex-matched controls. Twenty artifact-free 2 second EEG epochs during resting with closed eyes were analyzed (2-30 Hz bandpass, average reference for global and regional complexities, local EEG gradient time series for single channels).
  
  
  RESULTS
  Anterior regional Omega-Complexity was significantly increased in schizophrenics compared with controls (p < 0.001) and anterior regional Dimensional Complexity showed a trend for increase. Single channel Dimensional Complexity of local gradient waveshapes was prominently increased in the schizophrenics at the right precentral location (p = 0.003).
  
  
  CONCLUSIONS
  The results indicate a loosened cooperativity or coordination (vice versa: an increased independence) of the active brain processes in the anterior brain regions of the schizophrenics.
authors.affiliation: KEY Institute for Brain-Mind Research, University Hospital of Psychiatry, Zurick, Switzerland.
authors.forename: N
authors.initials: N
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Kuginuki
authors.forename: T
authors.initials: T
authors.lastname: Yagyu
authors.forename: T
authors.initials: T
authors.lastname: Kinoshita
authors.forename: T
authors.initials: T
authors.lastname: Koenig
authors.forename: R D
authors.initials: RD
authors.lastname: Pascual-Marqui
authors.forename: K
authors.initials: K
authors.lastname: Kochi
authors.forename: J
authors.initials: J
authors.lastname: Wackermann
authors.forename: D
authors.initials: D
authors.lastname: Lehmann
mesh_terms: D000208:Acute Disease; D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology; D004569:Electroencephalography / Q000295:instrumentation*; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D009415:Nerve Net / Q000503:physiopathology; D011569:Psychiatric Status Rating Scales; D012016:Reference Values; D012559:Schizophrenia / Q000175:diagnosis / Q000503:physiopathology*; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*