Spatial correlations of laminar BOLD and CBV responses to rat whisker stimulation with neuronal activity localized by Fos expression. Magn Reson Med 2004 Nov;52(5):1060-8
Date
10/28/2004Pubmed ID
15508149DOI
10.1002/mrm.20265Scopus ID
2-s2.0-7544245944 (requires institutional sign-in at Scopus site) 101 CitationsAbstract
The spatial relationship between a measured fMRI signal and its underlying neuronal activity remains unclear. One obstacle is the localization of neuronal activity; another is the spatial resolution of fMRI. In the present study, high-resolution BOLD and CBV fMRI experiments (voxel size: 156 x 156 x 2000 microm3) were conducted in the rat whisker barrel cortex at 3 T; neuronal activity across cortical layers was mapped using the Fos expression technique. Results show that BOLD response is weighted by blood volume and that pixels with high BOLD response can be located at the cortical surface or in deep layers, depending on local vasculature. In contrast to BOLD response, the pixels with high CBV response were consistently clustered in the deep cortical layers. Percentage-CBV change in cortical layers IV-V was 7.3 +/- 1.5%, which was significantly higher than in layers I-III (4.1 +/- 0.9%) and VI (4.3 +/- 0.7%) (mean +/- SEM). The laminar distribution of CBV response correlates well with neuronal activity localized by Fos expression. We conclude that neuronal activity can be inferred from CBV fMRI data with high spatial accuracy. The data indicate that both intracolumn functional connectivity and neurovascular coupling can be studied using CBV fMRI.
Author List
Lu H, Patel S, Luo F, Li SJ, Hillard CJ, Ward BD, Hyde JSAuthor
Cecilia J. Hillard PhD Associate Dean, Center Director, Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBrain Mapping
Cerebrovascular Circulation
Contrast Media
Echo-Planar Imaging
Electric Stimulation
Genes, fos
Image Enhancement
Male
Proto-Oncogene Proteins c-fos
Rats
Rats, Sprague-Dawley
Vibrissae