Skip Navigation


Cerebral Cortex Advance Access originally published online on December 5, 2007
Cerebral Cortex 2008 18(8):1814-1827; doi:10.1093/cercor/bhm208
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Data
Right arrow All Versions of this Article:
18/8/1814    most recent
bhm208v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Schridde, U.
Right arrow Articles by Blumenfeld, H.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Schridde, U.
Right arrow Articles by Blumenfeld, H.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2007. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org

Negative BOLD with Large Increases in Neuronal Activity

Ulrich Schridde1, Manjula Khubchandani2, Joshua E. Motelow1, Basavaraju G. Sanganahalli2,3, Fahmeed Hyder2,3,4 and Hal Blumenfeld1,3,5,6

1 Department of Neurology, 2 Department of Diagnostic Radiology, 3 Quantitative Neuroscience with Magnetic Resonance and Magnetic Resonance Research Center, 4 Department of Biomedical Engineering, 5 Department of Neurobiology, 6 Department of Neurosurgery, Yale University, New Haven, CT 06510, USA

Address correspondence to Hal Blumenfeld, MD PhD, Department of Neurology, Yale University, 333 Cedar Street, New Haven, CT 06520-8018, USA. Email: hal.blumenfeld{at}yale.edu.

Blood oxygen level–dependent (BOLD) functional magnetic resonance imaging (fMRI) is widely used in neuroscience to study brain activity. However, BOLD fMRI does not measure neuronal activity directly but depends on cerebral blood flow (CBF), cerebral blood volume (CBV), and cerebral metabolic rate of oxygen (CMRO2) consumption. Using fMRI, CBV, CBF, neuronal recordings, and CMRO2 modeling, we investigated how the signals are related during seizures in rats. We found that increases in hemodynamic, neuronal, and metabolic activity were associated with positive BOLD signals in the cortex, but with negative BOLD signals in hippocampus. Our data show that negative BOLD signals do not necessarily imply decreased neuronal activity or CBF, but can result from increased neuronal activity, depending on the interplay between hemodynamics and metabolism. Caution should be used in interpreting fMRI signals because the relationship between neuronal activity and BOLD signals may depend on brain region and state and can be different during normal and pathological conditions.

Key Words: cerebral blood flow • epilepsy • fMRI • hippocampus • neuroimaging • neurovascular coupling

Ulrich Schridde and Manjula Khubchandani have contributed equally to the study.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 J. Neurosci.Home page
D. J. Englot, A. M. Mishra, P. K. Mansuripur, P. Herman, F. Hyder, and H. Blumenfeld
Remote Effects of Focal Hippocampal Seizures on the Rat Neocortex
J. Neurosci., September 3, 2008; 28(36): 9066 - 9081.
[Abstract] [Full Text] [PDF]


Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.