Functional Imaging of the Monkey Brain

Nat Neurosci. 1999 Jun;2(6):555-62. doi: 10.1038/9210.


Functional magnetic resonance imaging (fMRI) has become an essential tool for studying human brain function. Here we describe the application of this technique to anesthetized monkeys. We present spatially resolved functional images of the monkey cortex based on blood oxygenation level dependent (BOLD) contrast. Checkerboard patterns or pictures of primates were used to study stimulus-induced activation of the visual cortex, in a 4.7-Tesla magnetic field, using optimized multi-slice, gradient-recalled, echo-planar imaging (EPI) sequences to image the entire brain. Under our anesthesia protocol, visual stimulation yielded robust, reproducible, focal activation of the lateral geniculate nucleus (LGN), the primary visual area (V1) and a number of extrastriate visual areas, including areas in the superior temporal sulcus. Similar responses were obtained in alert, behaving monkeys performing a discrimination task.

MeSH terms

  • Animals
  • Brain / blood supply
  • Brain / physiology*
  • Discrimination, Psychological / physiology
  • Geniculate Bodies / physiology
  • Macaca mulatta / physiology*
  • Magnetic Resonance Imaging*
  • Oxygen / blood
  • Photic Stimulation / methods
  • Time Factors
  • Visual Cortex / physiology
  • Visual Pathways / physiology


  • Oxygen