title: Changes in Event-Related Desynchronization and Synchronization during the Auditory Oddball Task in Schizophrenia Patients.
abstract: OBJECTIVE
  We studied differences in the spatiotemporal dynamics of cortical oscillation across brain regions of patients with schizophrenia and normal subjects during the auditory oddball task using magnetoencephalography (MEG) and electroencephalography (EEG).
  
  
  METHODS
  Ten right-handed male schizophrenia patients were studied. We used a newly developed adaptive spatial filtering algorithm optimized for robust source time-frequency reconstruction of MEG and EEG data, and obtained consecutive images in functional maps of event-related desynchronization (ERD) and synchronization (ERS) in theta, lower alpha (8-10 Hz), upper alpha (10-13 Hz), and beta bands.
  
  
  RESULTS
  Beta ERD power at 750-1000 ms in patients was significantly increased in large right upper temporal and parietal regions and small upper portions of bilateral dorsal frontal and dorsal-medial parietal regions. Theta ERS power in schizophrenic patients during the oddball task was significantly increased in the left temporal pole at 250-500 ms, and was significantly increased in dorsal, medial frontal, and anterior portions of the anterior cingulate cortex in both hemispheres, and the left portion of lateral temporal regions at 500-750 ms, compared to the control group (family-wise error correction p<0.05). Lower alpha ERS power was significantly decreased in the right occipital region at 500-750 ms and in the right midline parietal and bilateral occipital regions at 750-1000 ms. Upper alpha ERS power was significantly decreased in right midline parietal and left occipital regions at 750-1000 ms.
  
  
  CONCLUSIONS
  ERD/ERS changes were noted in the left temporal pole and midline frontal and anterior cingulate cortex in theta ERS, occipital lobe in alpha ERS, and right temporal-frontal-parietal, midline frontal, and anterior cingulate cortex in beta ERD. These findings may reflect disturbances in interaction among active large neuronal groups and their communication with each other that may be related to abnormal cognitive and psychopathological function.
  
  
  CONCLUSIONS
  Study of ERD and ERS by time-frequency analyses using MEG is useful to clarify data processing dysfunction in schizophrenia.
authors.affiliation: Fujimoto Hayasuzu Hospital, Yokakai Association, Miyazaki, Japan.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Fujimoto
authors.forename: Eiichi
authors.initials: E
authors.lastname: Okumura
authors.forename: Kouzou
authors.initials: K
authors.lastname: Takeuchi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kodabashi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Otsubo
authors.forename: Katsumi
authors.initials: K
authors.lastname: Nakamura
authors.forename: Masaki
authors.initials: M
authors.lastname: Sekine
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Kamiya
authors.forename: Yuji
authors.initials: Y
authors.lastname: Higashi
authors.forename: Miwa
authors.initials: M
authors.lastname: Tsuji
authors.forename: Susumu
authors.initials: S
authors.lastname: Shimooki
authors.forename: Toshiyo
authors.initials: T
authors.lastname: Tamura