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Brain region and activity-dependent properties of M for calibrated fMRI

Christina Y. Shu, Peter Herman, Daniel Coman, Basavaraju G. Sanganahalli, Helen Wang, Christoph Juchem, Douglas L. Rothman, Robin A. de Graaf, Fahmeed Hyder
2016 NeuroImage  
Since it is unclear if the range of M-values in human calibrated fMRI is due to regional/state differences, we conducted a 9.4T study to measure M-values across brain regions in deep (αchloralose) and  ...  Calibrated fMRI extracts changes in oxidative energy demanded by neural activity based on hemodynamic and metabolic dependencies of the blood oxygenation level-dependent (BOLD) response.  ...  Acknowledgments Thanks to Xenophon Papademetris for inputs on image analysis software and Bei Wang for assistance in animal surgeries.  ... 
doi:10.1016/j.neuroimage.2015.10.083 pmid:26529646 pmcid:PMC4691415 fatcat:5bcpf6junfdmjjbvk7x6wiglsm

Age-related differences in memory-encoding fMRI responses after accounting for decline in vascular reactivity

Peiying Liu, Andrew C. Hebrank, Karen M. Rodrigue, Kristen M. Kennedy, Jarren Section, Denise C. Park, Hanzhang Lu
2013 NeuroImage  
Based on the CVR-corrected fMRI signal, an age-related increase is now seen in both the left and right sides of IFG; and no brain regions showed a signal decrease with age.  ...  A common finding is that posterior regions of the brain manifest an age-related decrease in activation while the anterior regions show an age-related increase.  ...  .), and NIH R21 NS078656 (to H.L.). The authors are grateful to Bela Bhatia and Blair Flicker for assistance with the experiments.  ... 
doi:10.1016/j.neuroimage.2013.04.053 pmid:23624491 pmcid:PMC3694392 fatcat:4xyqs5qfnnhlboijkpkxkgk7wa

Energetics of neuronal signaling and fMRI activity

N. J. G. Maandag, D. Coman, B. G. Sanganahalli, P. Herman, A. J. Smith, H. Blumenfeld, R. G. Shulman, F. Hyder
2007 Proceedings of the National Academy of Sciences of the United States of America  
We discuss implications for interpreting fMRI data where stimulus-specific ⌬CMR O2 is generally small compared with baseline CMR O2. awake ͉ behavior ͉ calibrated fMRI ͉ glucose ͉ glutamate N oninvasive  ...  Localized energy consumption of neuronal and glial populations in MRI voxels has been evaluated (1), initially from 13 C MRS (2) and more recently from calibration of functional MRI (fMRI) (3).  ...  Seiji Ogawa, Simon Laughlin, Afonso Silva, Bharat Biswal, and Joshua Brumberg for comments on earlier drafts of the manuscript and Drs.  ... 
doi:10.1073/pnas.0709515104 pmid:18079290 pmcid:PMC2154468 fatcat:uh6qpaujrbdfxcee54ucr4od54

Insights from Neuroenergetics into the Interpretation of Functional Neuroimaging: An Alternative Empirical Model for Studying the Brain's Support of Behavior

Robert G Shulman, Fahmeed Hyder, Douglas L Rothman
2014 Journal of Cerebral Blood Flow and Metabolism  
Furthermore, the incremental signal depends on the baseline activity contradicting theoretical assumptions about linearity and insertion of mental modules.  ...  However, reproducible localization of these modules in the brain using functional magnetic resonance imaging (MRI) and positron emission tomography (PET) imaging has been elusive other than for sensory  ...  ACKNOWLEDGMENTS We thank the National Institute of Health for their support through the following grants: R01 AG034953, R01 MH067528, P30 NS052519.  ... 
doi:10.1038/jcbfm.2014.145 pmid:25160670 pmcid:PMC4269754 fatcat:7tzpzx4n6ne7vksbtb5gsxfmfu

A Primer on Functional Magnetic Resonance Imaging

Gregory G. Brown, Joanna E. Perthen, Thomas T. Liu, Richard B. Buxton
2007 Neuropsychology Review  
In the fourth section, calibrated fMRI, which uses BOLD and ASL to infer alterations of oxygen utilization during behavioral activation, is reviewed.  ...  In the second section, the biophysical mechanisms that alter the apparent transverse relaxation time, T * 2 , in blood oxygenation level dependent (BOLD) studies and the creation of BOLD activation maps  ...  There have been a wide range of M values reported in the literature, and M may vary over different brain regions and therefore should be measured for each experiment.  ... 
doi:10.1007/s11065-007-9028-8 pmid:17468956 fatcat:v4c7dkp3xvantedcmh62kmq55m

Direct estimation of evoked hemoglobin changes by multimodality fusion imaging

Theodore J. Huppert, Solomon G. Diamond, David A. Boas
2008 Journal of Biomedical Optics  
for imaging evoked cerebral hemodynamic changes in studies of brain activity.  ...  comparison to DOT alone, and show how this approach can provide cross-calibrated estimates of hemoglobin changes.  ...  The authors would also like to thank Ville Kolehmainen, Jari Kaipio, and Simon Arridge for useful discussions of this work.  ... 
doi:10.1117/1.2976432 pmid:19021411 pmcid:PMC2718838 fatcat:gc5nsiaamjhyfiu6ptxi5fae5m

Interpreting BOLD: towards a dialogue between cognitive and cellular neuroscience

Catherine N. Hall, Clare Howarth, Zebulun Kurth-Nelson, Anusha Mishra
2016 Philosophical Transactions of the Royal Society of London. Biological Sciences  
We declare we have no competing interests. 2 Cognitive neuroscience depends on the use of blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to probe brain function.  ...  in the relationship between BOLD and neuronal activity across different brain regions and experimental conditions (discussed below).  ...  coupling properties vary with net energy demand of a brain region.  ... 
doi:10.1098/rstb.2015.0348 pmid:27574302 pmcid:PMC5003850 fatcat:lgdgdei5izd35g7545tuuydbuy

Glutamatergic Function in the Resting Awake Human Brain is Supported by Uniformly High Oxidative Energy

Fahmeed Hyder, Robert K Fulbright, Robert G Shulman, Douglas L Rothman
2013 Journal of Cerebral Blood Flow and Metabolism  
Variations of CMR O2 and CMR glc from gray-matter regions and networks were within ±10% of means, suggesting that most areas required similar energy for ubiquitously high resting activity.  ...  We analyzed human data of electroencephalography (EEG), positron emission tomography (PET) maps of oxygen (CMR O2 ) and glucose (CMR glc ) utilization, and calibrated fMRI from a variety of experimental  ...  ACKNOWLEDGEMENTS FH thanks Xenophon Papademetris for help with BioImage Suite (www.  ... 
doi:10.1038/jcbfm.2012.207 pmid:23299240 pmcid:PMC3587823 fatcat:mlo7j3c5sjhxtmm634zvkvyhtq

Quantitative fMRI and oxidative neuroenergetics

Fahmeed Hyder, Douglas L. Rothman
2012 NeuroImage  
The blood oxygenation level-dependent (BOLD) signal, using deoxyhemoglobin as an endogenous paramagnetic contrast agent, exposes regions of interest in task-based and restingstate paradigms.  ...  Here we describe how studies of brain energy metabolism at Yale, especially with 13 C magnetic resonance spectroscopy and related techniques, contributed to development of quantitative functional brain  ...  Acknowledgments Thanks to colleagues at Yale University for insightful comments. Supported by National Institutes of Health Grants (R01 MH-067528 to FH, P30 NS-052519 to FH, R01 AG-034953 to DLR).  ... 
doi:10.1016/j.neuroimage.2012.04.027 pmid:22542993 pmcid:PMC3389300 fatcat:popox45ytvbzdgbzeysyxdutda

Hemodynamic Scaling of Task-Induced Signal Changes in Tumor Subjects

Tianming Qiu, N. U. Farrukh Hameed, Ching-Po Lin, Bharat B. Biswal, Jinsong Wu
2020 Frontiers in Human Neuroscience  
To account for these changes in fMRI activation signal, we used breath-hold tasks to mimic hemodynamic changes in brain tumor subjects and scaled the activation response.  ...  The task activation signals were calibrated on a voxel wise basis for all the subjects. Direct cortical stimulation was used to verify the scaled results of task-based fMRI.  ...  INTRODUCTION Blood oxygenation level dependent (BOLD) based fMRI is a non-invasive method for mapping human brain function by indirectly measuring neural activity.  ... 
doi:10.3389/fnhum.2020.569463 pmid:33132884 pmcid:PMC7566414 fatcat:rmlukg4ivrep3pg63w7nav2xxy

The Role of Cerebrovascular-Reactivity Mapping in Functional MRI: Calibrated fMRI and Resting-State fMRI

J. Jean Chen, Claudine J. Gauthier
2021 Frontiers in Physiology  
fMRI for that purpose.  ...  CVR and calibrated fMRI, and provides a view into the future of non-invasive CVR measurement.  ...  FUNDING The writing of this review was supported by the Canadian Institutes of Health Research (CIHR), the Heart and Stroke Foundation, and the Michal and Renata Hornstein Chair in Cardiovascular Imaging  ... 
doi:10.3389/fphys.2021.657362 pmid:33841190 pmcid:PMC8027080 fatcat:rr7riv4advfitaovxhhgojyu2m

Separating vascular and neuronal effects of age on fMRI BOLD signals [article]

Kamen A. Tsvetanov, Richard N.A. Henson, James B. Rowe
2020 arXiv   pre-print
We review current approaches to dissociate neuronal and vascular components of BOLD-fMRI of regional activity and functional connectivity.  ...  However, although fMRI data are often interpreted in terms of neuronal activity, the blood-oxygen-level-dependent (BOLD) signal measured by fMRI includes contributions of both vascular and neuronal factors  ...  The subscript CVR denotes the hypercapnia condition and the parameter M defines the maximum possible BOLD signal change for a brain region.  ... 
arXiv:1912.02899v2 fatcat:tq4mkl776vdzpialwczs5hgama

Functional MRI Limitations and Aspirations [chapter]

Peter A. Bandettini
2009 Neural Correlates of Thinking  
In addition, issues of how sensitive functional MRI is in detecting brain activity and how deeply we can interpret the signal changes are explored.  ...  This chapter describes the basics, limits, and future directions of one of the more effective tools we have to observe the human brain while it is functioningfunctional MRI.  ...  brain activation timing within the same voxel or region of the brain that are no smaller than 100 ms. • Able to detect inhibitory interaction, with no temporal limit, between connected and interacting  ... 
doi:10.1007/978-3-540-68044-4_2 fatcat:6jln3c73djefhcxumollk4viji

The Relationship Between M in "Calibrated fMRI" and the Physiologic Modulators of fMRI

Hanzhang Lu, Joanna Hutchison, Feng Xu, Bart Rypma
2011 The Open Neuroimaging Journal  
The "calibrated fMRI" technique requires a hypercapnia calibration experiment in order to estimate the factor "M".  ...  The lack of correlation may be explained by the counteracting effect of venous oxygenation and CBF on the M factor, such that the actual M value of an individual may be mostly dependent on other parameters  ...  INTRODUCTION Blood-Oxygenation-Level-Dependent (BOLD) fMRI is based on MRI signal changes associated with indirect effects of neural activation [1] .  ... 
doi:10.2174/1874440001105010112 pmid:22276083 pmcid:PMC3263507 fatcat:u4f3puscorcmpppluhyj4yclpe

Potentials and Challenges for Arterial Spin Labeling in Pharmacological Magnetic Resonance Imaging

D. J. J. Wang, Y. Chen, M. A. Fernandez-Seara, J. A. Detre
2011 Journal of Pharmacology and Experimental Therapeutics  
These two characteristics make ASL an ideal tool for phMRI to study both intravenous and oral drug action as well as to understand drug effects on baseline brain function and on brain activation to cognitive  ...  As an alternative method, ASL provides noninvasive, absolute quantification of cerebral blood flow both at rest and during task activation.  ...  Interested readers can refer to earlier reviews addressing the general properties of ASL and BOLD contrast for fMRI studies (Aguirre et al. 2005, Detre and as well as reviews on existing BOLD phMRI studies  ... 
doi:10.1124/jpet.110.172577 pmid:21317356 pmcid:PMC3083105 fatcat:e6glikhhpzdmvkggcjvg6m7ht4
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