BOLD fMRI of visual and somatosensory-motor stimulations in baboons

Hsiao Ying Wey, Jinqi Li, C. Ákos Szabó, Peter T. Fox, M. Michelle Leland, Lisa Jones, Timothy Q. Duong

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


Baboon, with its large brain size and extensive cortical folding compared to other non-human primates, serves as a good model for neuroscience research. This study reports the implementation of a baboon model for blood oxygenation level-dependent (BOLD) fMRI studies (1.5×1.5×4 mm resolution) on a clinical 3T-MRI scanner. BOLD fMRI responses to hypercapnic (5% CO2) challenge, 10Hz flicker visual, and vibrotactile somatosensory-motor stimulations were investigated in baboons anesthetized sequentially with isoflurane and ketamine. Hypercapnia evoked robust BOLD increases. Paralysis was determined to be necessary to achieve reproducible functional activations within and between subjects under our experimental conditions. With optimized anesthetic doses (0.8-1.0% isoflurane or 6-8mg/kg/h ketamine) and adequate paralysis (vecuronium, 0.2mg/kg), robust activations were detected in the visual (V), primary (S1) and secondary (S2) somatosensory, primary motor (M cortices), supplementary motor area (SMA), lateral geniculate nucleus (LGN) and thalamus (Th). Data were tabulated for 11 trials under isoflurane and 10 trials under ketamine on 5 baboons. S1, S2, M, and V activations were detected in essentially all trials (90-100% of the time, except 82% for S2 under isoflurane and 70% for M under ketamine). LGN activations were detected 64-70% of the time under both anesthetics. SMA and Th activations were detected 36-45% of the time under isoflurane and 60% of the time under ketamine. BOLD percent changes among different structures were slightly higher under ketamine than isoflurane (0.75% versus 0.58% averaging all structures), but none was statistically different (P>0.05). This baboon model offers an opportunity to non-invasively image brain functions and dysfunctions in large non-human primates.

Original languageEnglish (US)
Pages (from-to)1420-1427
Number of pages8
Issue number4
StatePublished - Oct 2010


  • Anesthetic
  • Animal models
  • Blood oxygenation level-dependent (BOLD) fMRI
  • Brain mapping
  • Cerebral blood flow
  • Non-human primates
  • Thalamus

ASJC Scopus subject areas

  • Neurology
  • Cognitive Neuroscience


Dive into the research topics of 'BOLD fMRI of visual and somatosensory-motor stimulations in baboons'. Together they form a unique fingerprint.

Cite this