title: Alpha-band desynchronization in human parietal area during reach planning.
abstract: OBJECTIVE
  The symptoms with optic ataxia suggest that simple and visually guided hand movements are controlled by 2 different neural substrates. To assess the differential frequency-coded posterior parietal cortex (PPC) role in planning visuo-motor goal-directed tasks, we studied the action specificity of event-related desynchronization (ERD) in this area.
  
  
  METHODS
  We investigated cortical activity by electroencephalography, while 16 healthy subjects performed self-paced reaching or wrist extension (control) movements. Time-frequency representations were calculated for each movement during the preparatory period.
  
  
  RESULTS
  ERD dynamics in upper alpha-band indicated that preparing a goal-directed action activates contralateral PPC to the moving hand around 1.2s before starting the movement, while this activation is later (around 0.7s) in preparing a not-goal-directed action. The posterior dominant rhythm had peak frequency of lower alpha-band at bilateral parietal.
  
  
  CONCLUSIONS
  Posterior parietal cortex encodes goal-directed movement preparation through upper alpha-band activity, whereas general attention is processed via lower alpha-band oscillations.
  
  
  CONCLUSIONS
  Preparing to reach an object engages posterior parietal cortex earlier than a not-goal directed movement.
authors.affiliation: Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan; Research and Educational Unit of Leaders for Integrated Medical System, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Fumuro
authors.affiliation: Research and Educational Unit of Leaders for Integrated Medical System, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan; Human Brain Research Center, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Matsuhashi
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Miyazaki
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan; Department of Respiratory Care and Sleep Control Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Morito
authors.initials: M
authors.lastname: Inouchi
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan; Department of Respiratory Care and Sleep Control Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan; Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Takefumi
authors.initials: T
authors.lastname: Hitomi
authors.affiliation: Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Riki
authors.initials: R
authors.lastname: Matsumoto
authors.affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Takahashi
authors.affiliation: Human Brain Research Center, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Hidenao
authors.initials: H
authors.lastname: Fukuyama
authors.affiliation: Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, 54 Shogoin-kawaracho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: akio@kuhp.kyoto-u.ac.jp.
authors.forename: Akio
authors.initials: A
authors.lastname: Ikeda
mesh_terms: D000328:Adult; D000513:Alpha Rhythm / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods*; D004569:Electroencephalography / Q000379:methods; D005260:Female; D006225:Hand / Q000502:physiology*; D006801:Humans; D033182:Intention; D008297:Male; D009068:Movement / Q000502:physiology*; D010296:Parietal Lobe / Q000502:physiology*; D055815:Young Adult
keywords: Alpha-band desynchronization; Motor planning; Parietal area; Reaching