High-resolution mapping of iso-orientation columns by fMRI

Nat Neurosci. 2000 Feb;3(2):164-9. doi: 10.1038/72109.


Blood-oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is an important tool for localizing brain functions in vivo. However, the ability of BOLD fMRI to map cortical columnar structures is highly controversial, as the ultimate functional specificity of BOLD remains unknown. Here we report a biphasic BOLD response to visual stimulation in the primary visual cortex of cats. In functional imaging, the initial BOLD signal decrease accurately labeled individual iso-orientation columns. In contrast, the delayed positive BOLD changes indicated the pattern of overall activation in the visual cortex, but were less suited to discriminate active from inactive columns.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Brain Mapping / methods*
  • Cats
  • Magnetic Resonance Imaging / methods
  • Oxygen / blood
  • Photic Stimulation
  • Sensitivity and Specificity
  • Signal Processing, Computer-Assisted
  • Visual Cortex / blood supply
  • Visual Cortex / physiology*
  • Visual Pathways / physiology
  • Visual Perception / physiology


  • Oxygen