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The Spatial Dependence of the Poststimulus Undershoot as Revealed by High-Resolution BOLD- and CBV-Weighted fMRI

Essa Yacoub, Kamil Ugurbil, Noam Harel
2005 Journal of Cerebral Blood Flow and Metabolism  
The hemodynamic response to neural activity consists of changes in blood flow, blood volume and oxygen metabolism.  ...  This poststimulus undershoot has been modeled and investigated to characterize the physiological mechanisms (cerebral blood flow (CBF), cerebral blood volume (CBV), and cerebral oxygen consumption) associated  ...  Introduction Increases in neural activity in the brain are accompanied by elevations in cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral oxygen consumption (CMRO 2 ).  ... 
doi:10.1038/sj.jcbfm.9600239 pmid:16222242 fatcat:plmvp4kofrdfrcb7dzkyb2tuti

The spatial dependence of the post-stimulus undershoot as revealed by high resolution bold and CBV weighted fMRI

Essa Yacoub, Kamil Ugurbil, Noam Harel
2005 Journal of Cerebral Blood Flow and Metabolism  
The hemodynamic response to neural activity consists of changes in blood flow, blood volume and oxygen metabolism.  ...  This poststimulus undershoot has been modeled and investigated to characterize the physiological mechanisms (cerebral blood flow (CBF), cerebral blood volume (CBV), and cerebral oxygen consumption) associated  ...  Introduction Increases in neural activity in the brain are accompanied by elevations in cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral oxygen consumption (CMRO 2 ).  ... 
doi:10.1038/sj.jcbfm.9591524.0335 fatcat:3kxph5wndnhs3iw27rwj3b242y

On the origin of sustained negative BOLD response

Marta Moraschi, Mauro DiNuzzo, Federico Giove
2012 Journal of Neurophysiology  
Analysis of oxygen metabolism implies a neural origin for the negative BOLD response in human visual cortex.  ...  This increase could be due to different coupling patterns between blood flow and oxygen consumption.  ...  However, LFP remains correlated to BOLD even in those conditions that cause an uncoupling between BOLD and spiking.  ... 
doi:10.1152/jn.01199.2011 pmid:22723671 fatcat:rmhb6yceuzcwhf77anpjof2uc4

Page 406 of Journal of Cognitive Neuroscience Vol. 17, Issue 3 [page]

2005 Journal of Cognitive Neuroscience  
Negative dip in BOLD fMRI is caused by blood flowoxygen consumption uncoupling in humans. Neuroimage, 15, 98-102 Rothi, L. J. G., Raymer, A. M., Maher, L., Greenwald, M., & Morris, M. (1991).  ...  Empirical analyses of BOLD fMRI statistics: I. Spatially unsmoothed data collected under null-hypothesis conditions Veuroimage, 5, 179-197 Volume 17, Number 3  ... 

Functional neuroimaging: a physiological perspective

Lin
2010 Frontiers in Neuroenergetics  
In addition, the task-induced increases in CBF were most likely mediated by anaerobic glycolysis rather than oxygen demand.  ...  However, controversies were also raised as regards the metabolic pathways (oxidative vs. non-oxidative) for meeting the energy demand and driving the increases in cerebral blood flow (CBF) during brain  ...  Such uncoupling of CBF and CMRO 2 is the basis for the blood oxygenation level-dependent (BOLD) functional MRI (fMRI) contrast (Kwong et al., 1992; Ogawa et al., 1992) .  ... 
doi:10.3389/fnene.2010.00017 pmid:20725632 pmcid:PMC2916670 fatcat:di6bd3wsandfpfahkqe4vh6nge

Polarographic Electrode Measures of Cerebral Tissue Oxygenation: Implications for Functional Brain Imaging

Kate Bartlett, Mohamad Saka, Myles Jones
2008 Sensors  
A principle factor influencing blood oxygenation, the cerebral metabolic rate of oxygen consumption is poorly understood and as such, data from imaging techniques are difficult to interpret in terms of  ...  The changes in blood flow, blood volume and oxygenation that accompany focal increases in neural activity are collectively referred to as the hemodynamic response and form the basis of non-invasive neuroimaging  ...  Acknowledgements This review was supported by MRC New Investigator Award G0501127. The authors would also like to thank Mrs Marion Simkins for proof reading the manuscript and Drs Jason Berwick, Ying  ... 
doi:10.3390/s8127649 pmid:27873951 pmcid:PMC3790982 fatcat:iwqqd4lymvbgva2tbejmllhaxe

Intraoperative Human Functional Brain Mapping Using Optical Intrinsic Signal Imaging [chapter]

Sameer A., Vijay Yanamadala, Emad N.
2012 Advances in Brain Imaging  
This so-called blood oxygenation level dependent (BOLD) contrast is by far the most common in fMRI studies.  ...  J Cereb Blood Flow Metab, 1997. 17(10): p. 1040-7. [11] Hoge, R.D., et al., Linear coupling between cerebral blood flow and oxygen consumption in activated human cortex.  ... 
doi:10.5772/29255 fatcat:7lardjth7vh4bhyqnjwrzal2z4

Technical aspects and utility of fMRI using BOLD and ASL

John A. Detre, Jiongjiong Wang
2002 Clinical Neurophysiology  
In particular, fMRI methods based on blood oxygenation level dependent (BOLD) contrast and arterial spin labeling (ASL) perfusion contrast have enabled imaging of changes in blood oxygenation and cerebral  ...  blood flow (CBF).  ...  Table 1 1 Comparison between imaging characteristics of fMRI using BOLD and ASL perfusion contrasts BOLD ASL perfusion Signal mechanism Blood flow, blood volume, oxygenation consumption Blood flow  ... 
doi:10.1016/s1388-2457(02)00038-x pmid:11976042 fatcat:7d6aw4iizfh3lmy53fjadpnqeu

Neural–metabolic coupling in the central visual pathway

Ralph D. Freeman, Baowang Li
2016 Philosophical Transactions of the Royal Society of London. Biological Sciences  
One contribution of 15 to a Theo Murphy meeting issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'.  ...  However, fMRI is a powerful technique because in an activated brain area, blood flow increases much more than oxygen metabolic rate [1, 2] .  ...  Tissue oxygen is directly related to the BOLD signal, which is the primary measurement in fMRI. It can be readily assessed by a micro-sensor in an in vivo preparation.  ... 
doi:10.1098/rstb.2015.0357 pmid:27574310 pmcid:PMC5003858 fatcat:niqdwtg3enavfm3rvmfqfb6fre

Negative BOLD with Large Increases in Neuronal Activity

Ulrich Schridde, Manjula Khubchandani, Joshua E. Motelow, Basavaraju G. Sanganahalli, Fahmeed Hyder, Hal Blumenfeld
2007 Cerebral Cortex  
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 (CMRO 2 ) consumption.  ...  We also thank Miro Enev for contributing software for data analysis, Dr Bei Wang for technical assistance in animal preparation, Dr Peter Herman for help with the recordings, and the engineering staff  ... 
doi:10.1093/cercor/bhm208 pmid:18063563 pmcid:PMC2790390 fatcat:p6zn2fhhzzeife6jqxwdvyfa7i

Imaging oxygen consumption in forepaw somatosensory stimulation in rats under isoflurane anesthesia

Zhaohui M. Liu, Karl F. Schmidt, Kenneth M. Sicard, Timothy Q. Duong
2004 Magnetic Resonance in Medicine  
Combined cerebral blood flow signals (CBF) and blood oxygenation level-dependent (BOLD) fMRI signals were simultaneously measured with the use of a multislice continuous arterial spin labeling (CASL) technique  ...  In contrast to ␣-chloralose, which is the most widely used anesthetic in forepaw-stimulation fMRI studies of rats under mechanical ventilation, isoflurane (1.1-1.2%) provided a stable anesthesia level  ...  metabolic rate of oxygen (CMRO 2 ) is tightly coupled to the cerebral blood flow (CBF) and the cerebral metabolic rate of glucose (CMR glucose ) (1) .  ... 
doi:10.1002/mrm.20148 pmid:15282809 pmcid:PMC2962950 fatcat:w5mysjszpfezniztpnnpfda5ve

Mechanistic Mathematical Modeling Tests Hypotheses of the Neurovascular Coupling in fMRI

Karin Lundengård, Gunnar Cedersund, Sebastian Sten, Felix Leong, Alexander Smedberg, Fredrik Elinder, Maria Engström, Jörn Diedrichsen
2016 PLoS Computational Biology  
Functional magnetic resonance imaging (fMRI) measures brain activity by detecting the blood-oxygen-level dependent (BOLD) response to neural activity.  ...  to the BOLD response in fMRI.  ...  Witt for valuable discussions regarding fMRI image analysis and the test subjects for donating their time in the scanner. Author Contributions Conceived and designed the experiments: KL ME.  ... 
doi:10.1371/journal.pcbi.1004971 pmid:27310017 pmcid:PMC4911100 fatcat:rtlc43l52rhwze3vjt2uhpmze4

ON THE CHARACTERISTICS OF FUNCTIONAL MAGNETIC RESONANCE IMAGING OF THE BRAIN

S. Ogawa, R. S. Menon, S.-G. Kim, K. Ugurbil
1998 Annual Review of Biophysics and Biomolecular Structure  
Finally, the advantage of fMRI mapping is shown in a few examples. Reviewing the vast number of recent fMRI application that have now been reported is beyond the scope of this article.  ...  The question of spatial resolution of fMRI, which must be dictated by the vascular structure serving the functional system, is discussed based on various fMRI observations.  ...  The negative dip has been attributed to an increase of the deoxyhemoglobin content in the tissue caused by the increase of the metabolic load as shown by optical imaging data (39) on an awake monkey.  ... 
doi:10.1146/annurev.biophys.27.1.447 pmid:9646874 fatcat:jdp5zlw7jnapvgmhhbeafswoqi

Reproducing the Hemoglobin Saturation Profile, a Marker of the Blood Oxygenation Level Dependent (BOLD) fMRI Effect, at the Microscopic Level

Constantinos Hadjistassou, Keri Moyle, Yiannis Ventikos, Jodie L. Rummer
2016 PLoS ONE  
Brain activation, mimicked by dynamic transitions in cerebral blood velocity (CBv) and oxidative metabolism (CMR O 2 ), is simulated by normalized changes in m = (ΔCBv/CBv)/(ΔCMR O 2 /CMR O 2 ) of values  ...  Finally, factoring in neurovascular effects, we show that no initial dip will be observed unless there is a time delay in the onset of increased CBv relative to CMR O 2 .  ...  We argue that at the local microscopic brain level m, rather than n, is a more objective measure for blood flow studies and coupling and uncoupling comparisons for blood flow and oxygen metabolism at the  ... 
doi:10.1371/journal.pone.0149935 pmid:26939128 pmcid:PMC4777512 fatcat:peewqcjfe5dqtawdjwzmtmcfcm

Microvascular Oxygen Tension and Flow Measurements in Rodent Cerebral Cortex during Baseline Conditions and Functional Activation

Mohammad A Yaseen, Vivek J Srinivasan, Sava Sakadžić, Harsha Radhakrishnan, Iwona Gorczynska, Weicheng Wu, James G Fujimoto, David A Boas
2010 Journal of Cerebral Blood Flow and Metabolism  
Oxygen extraction is linearly related to flow in ascending venules, suggesting that flow in ascending venules closely matches oxygen demand of the drained territory.  ...  Cerebral blood flow and pO 2 measurements displayed heterogeneity over distances irresolvable with fMRI and positron emission tomography.  ...  oxygen (CMRO 2 ), involves the dynamic uncoupling of CBF and oxygen consumption, with disproportionately larger increases in CBF compared with CMRO 2 .  ... 
doi:10.1038/jcbfm.2010.227 pmid:21179069 pmcid:PMC3070982 fatcat:6ddfollafbdvfad2bbnbo2v27u
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