title: Cortical activation during optokinetic stimulation - an fMRI study.
abstract: CONCLUSIONS
  Activation of cortical areas related to visual motion processing and control of eye movement, and deactivation of parieto-insular vestibular cortices (PIVC) were revealed by functional magnetic resonance imaging (fMRI) with small-field optokinetic stimulation (OKS). The results agreed well with those of previous studies, which indicates that the current protocol is reliable enough to be used as a clinical examination.
  
  
  OBJECTIVE
  To propose an fMRI set-up with OKS that is reliable and simple enough to be performed as a clinical test.
  
  
  METHODS
  Ten right-handed healthy volunteers participated in this study. fMRI was used to measure blood oxygen level-dependent (BOLD) signal increases (contrast: OKS - rest) and decreases (contrast: rest - OKS) during small-field OKS. Functional images were acquired using a standard clinical scanner operating at a magnetic field strength of 1.5 T. The data were analyzed by statistical parametric mapping (SPM2), and the significance level was set at p<0.001, uncorrected.
  
  
  RESULTS
  BOLD signal increases were observed in the visual association area of both hemispheres (BA19) (MT/V5), primary visual cortex (BA17) of the right hemisphere, bilateral superior parietal lobules (BA7), and bilateral frontal eye fields (BA6). Decreases of BOLD signals were observed in the PIVC bilaterally.
authors.affiliation: Department of Otolaryngology, Kobe City Medical Center General Hospital, Kobe, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Naito
authors.forename: Michio
authors.initials: M
authors.lastname: Senda
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Okada
authors.forename: Shogo
authors.initials: S
authors.lastname: Shinohara
authors.forename: Keizo
authors.initials: K
authors.lastname: Fujiwara
authors.forename: Shin-Ya
authors.initials: SY
authors.lastname: Hori
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Tona
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamazaki
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009039:Motion Perception; D017120:Nystagmus, Optokinetic; D015835:Ocular Motility Disorders / Q000175:diagnosis; D014793:Visual Cortex / Q000502:physiology*