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Modeling of region-specific fMRI BOLD neurovascular response functions in rat brain reveals residual differences that correlate with the differences in regional evoked potentials

Christopher P. Pawela, Anthony G. Hudetz, B. Douglas Ward, Marie L. Schulte, Rupeng Li, Dennis S. Kao, Matthew C. Mauck, Younghoon R. Cho, Jay Neitz, James S. Hyde
2008 NeuroImage  
To explain these differences, the BOLD neurovascular response function was modeled.  ...  The response of the rat visual system to flashes of blue light has been studied by blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI).  ...  Acknowledgements This work was supported by grants EB000215, EB000215-S1, and GM56398 from the National Institutes of Health, and DABK39-03-C-0058 from the Counterdrug Technology Assessment Center, Office  ... 
doi:10.1016/j.neuroimage.2008.02.022 pmid:18406628 pmcid:PMC2483240 fatcat:vzrxxcjb4vef5m6y3ptmd66kpa

Mapping the functional network of medial prefrontal cortex by combining optogenetics and fMRI in awake rats

Zhifeng Liang, Glenn D.R. Watson, Kevin D. Alloway, Gangchea Lee, Thomas Neuberger, Nanyin Zhang
2015 NeuroImage  
Here we combined optogenetic stimulation and functional magnetic resonance imaging (opto-fMRI) to reveal the network of brain regions functionally activated by mPFC outputs in awake rodents.  ...  Given its vital importance, investigating the function of individual mPFC circuits in animal models has provided critical insight into the neural basis underlying different behaviors and psychiatric conditions  ...  the National Institute of Neurological Disorders and Stroke.  ... 
doi:10.1016/j.neuroimage.2015.05.036 pmid:26002727 pmcid:PMC4512884 fatcat:4ojeclql2zf4bahgeezwvipxsi

Functional magnetic resonance imaging in chronic ischaemic stroke

Evelyn M. R. Lake, Paolo Bazzigaluppi, Bojana Stefanovic
2016 Philosophical Transactions of the Royal Society of London. Biological Sciences  
Indeed, the perceived clinical potential of BOLD fMRI remains unrealized. In this review, we focus on the application of fMRI to studies of brain function in the chronic stage of stroke progression.  ...  Despite its potential as a sensitive non-invasive in vivo marker of brain function that may aid in the development of new treatments, blood oxygenation level-dependent (BOLD) functional magnetic resonance  ... 
doi:10.1098/rstb.2015.0353 pmid:27574307 pmcid:PMC5003855 fatcat:qv4wou6p7vdvlolbhdgznpykou

Coupling Mechanism and Significance of the BOLD Signal: A Status Report

Elizabeth M.C. Hillman
2014 Annual Review of Neuroscience  
The blood-oxygen-level-dependent (BOLD) signal, detected in fMRI, reflects changes in deoxyhemoglobin driven by localized changes in brain blood flow and blood oxygenation, which are coupled to underlying  ...  Functional magnetic resonance imaging (fMRI) provides a unique view of the working human mind.  ...  The author acknowledges support from NINDS 1R01NS063226,  ... 
doi:10.1146/annurev-neuro-071013-014111 pmid:25032494 pmcid:PMC4147398 fatcat:yrptkxd6xbhubgu3bpnco4xbua

Neurovascular and neurometabolic couplings in dynamic calibrated fMRI: transient oxidative neuroenergetics for block-design and event-related paradigms

D. S. Fahmeed Hyder
2010 Frontiers in Neuroenergetics  
Functional magnetic resonance imaging (fMRI) with blood-oxygenation level dependent (BOLD) contrast is an important tool for mapping brain activity.  ...  Interest in quantitative fMRI has renewed awareness in importance of oxidative neuroenergetics, as reflected by cerebral metabolic rate of oxygen consumption ( ), CMR O 2 for supporting brain function.  ...  In each case, the comparison showed that the residual "noise" in modeling was smaller than the measurement uncertainty.  ... 
doi:10.3389/fnene.2010.00018 pmid:20838476 pmcid:PMC2936934 fatcat:kq73jrpmhvbozdilpxqxxaojxa

Quantitative basis for neuroimaging of cortical laminae with calibrated functional MRI

P. Herman, B. G. Sanganahalli, H. Blumenfeld, D. L. Rothman, F. Hyder
2013 Proceedings of the National Academy of Sciences of the United States of America  
Results During forepaw stimulation in the rat we measured dynamic responses of BOLD, CBV, and CBF at 11.7 T with different fMRI methods and then combined these data to calibrate the fMRI signal to calculate  ...  that changes in cerebral metabolic rate of oxygen consumption (CMR O2 ) can be calculated with a biophysical model of BOLD (6).  ...  This work was supported by National Institutes of Health Grants R01 MH-067528 and P30 NS-052519 (to F.H.), R01 AG-034953 (to D.L.R.), and R01 NS-066974 (to H.B.).  ... 
doi:10.1073/pnas.1307154110 pmid:23980158 pmcid:PMC3773779 fatcat:5zopaejiufg63mltccnmaqp6ti

Resting-state hemodynamics are spatiotemporally coupled to synchronized and symmetric neural activity in excitatory neurons

Ying Ma, Mohammed A. Shaik, Mariel G. Kozberg, Sharon H. Kim, Jacob P. Portes, Dmitriy Timerman, Elizabeth M. C. Hillman
2016 Proceedings of the National Academy of Sciences of the United States of America  
In stimulus-evoked studies, the positive fMRI blood oxygen level-dependent (BOLD) signal corresponds to a decrease in [HbR] caused by a local increase in blood flow leading to over-oxygenation of the region  ...  In resting-state fMRI, hemodynamic fluctuations have been found to exhibit patterns of bilateral synchrony, with correlated regions inferred to have functional connectivity.  ...  (iii) The analysis approach used here assumed a neurovascular coupling model in which neural events would (directly or indirectly) evoke a stereotyped Δ[HbT] response, a model with a strong physiological  ... 
doi:10.1073/pnas.1525369113 pmid:27974609 pmcid:PMC5206542 fatcat:woxqfamtubfuhnwfpq3fhvnouq

Time to wake up: Studying neurovascular coupling and brain-wide circuit function in the un-anesthetized animal

Yu-Rong Gao, Yuncong Ma, Qingguang Zhang, Aaron T. Winder, Zhifeng Liang, Lilith Antinori, Patrick J. Drew, Nanyin Zhang
2017 NeuroImage  
Here, we review work showing that neurovascular coupling and brain circuit function in the awake animal are profoundly different from those in the anesthetized state.  ...  While there has been extensive study of neurovascular coupling in anesthetized animal models, anesthesia causes large disruptions of brain metabolism, neural responsiveness and cardiovascular function.  ...  NZ is supported by R01MH098003 from the National Institute of Mental Health and R01NS085200 from the National Institute of Neurological Disorders and Stroke.  ... 
doi:10.1016/j.neuroimage.2016.11.069 pmid:27908788 pmcid:PMC5526447 fatcat:apmur7ojhbasrgexfswze6lhme

Imaging Neurovascular Function and Functional Recovery after Stroke in the Rat Striatum Using Forepaw Stimulation

Yen-Yu Ian Shih, Shiliang Huang, You-Yin Chen, Hsin-Yi Lai, Yu-Chieh Jill Kao, Fang Du, Edward S Hui, Timothy Q Duong
2014 Journal of Cerebral Blood Flow and Metabolism  
This study shows that fMRI signals could differ significantly from LFP and that the observed negative CBV response has potential to serve as a marker for striatal functional integrity in rats.  ...  with LFP (r ¼ 0.04), demonstrating that the negative striatal CBV response is not originated from net regional inhibition.  ...  In normal rats, neurovascular fMRI of the striatum in normal and stroke rats Y-YI Shih et al function in the cortex and the striatum was evaluated by correlating CBV fMRI response with LFP results.  ... 
doi:10.1038/jcbfm.2014.103 pmid:24917039 pmcid:PMC4158660 fatcat:oeov6zfbjrhmlkd2242m6dkhbm

Spatial contribution of hippocampal BOLD activation in high-resolution fMRI

Yoshifumi Abe, Tomokazu Tsurugizawa, Denis Le Bihan, Luisa Ciobanu
2019 Scientific Reports  
Here, we take advantage of these two benefits to investigate the spatial characteristics of the hippocampal activation in a rat model before and after changing the hippocampal plasticity by long-term potentiation  ...  We found that the hippocampal BOLD signals evoked by electrical stimulation at the perforant pathway increased more at the radiatum layer of the hippocampal CA1 region than at the pyramidal cell layer.  ...  Acknowledgements The authors acknowledge funding from Louis-Jeantet and Louis D. Foundations (DLB) and CEA bottom-up programme (LC). YA thanks B. Djemai for support with general animal handling.  ... 
doi:10.1038/s41598-019-39614-3 pmid:30816226 pmcid:PMC6395694 fatcat:q54phw6tdbhibbfw3ehc2omsvq

Pitfalls in fMRI

Sven Haller, Andreas J. Bartsch
2009 European Radiology  
Several different techniques allow a functional assessment of neuronal activations by magnetic resonance imaging (fMRI).  ...  Consequently, the term 'fMRI' is often used synonymously with BOLD imaging.  ...  Acknowledgements We thank Georg Homola for assisting with data analyses and figure generations. Andreas Bartsch's work has been generously facilitated by the Vera and Volker Doppelfeld Foundation.  ... 
doi:10.1007/s00330-009-1456-9 pmid:19504107 fatcat:dnd7t5ite5dj3fjm7rlm4hi2dm

Remote Changes in Cortical Excitability after Experimental Traumatic Brain Injury and Functional Reorganization

Derek R. Verley, Daniel Torolira, Brandon Pulido, Boris Gutman, Anatol Bragin, Andrew Mayer, Neil G. Harris
2018 Journal of Neurotrauma  
We used the adult rat controlled cortical impact injury model to study the ipsilesional forelimb map evoked by electrical stimulation of the affected limb, as well as the contralesional forelimb map evoked  ...  The results show a transient trans-hemispheric shift in the ipsilesional cortical map as indicated by fMRI, remote contralesional increases in cortical excitability that occur in spatially similar regions  ...  The project described was also supported in part CORTICAL EXCITABILITY AND FUNCTIONAL REORGANIZATION  ... 
doi:10.1089/neu.2017.5536 pmid:29717625 pmcid:PMC6196752 fatcat:ox6doxo7cbfqnbkxkkozytukfe

Spontaneous activity changes in large-scale cortical networks in older adults couple to distinct hemodynamic morphology [article]

Tatiana Sitnikova, Jeremy W Hughes, Casey M Howard, Kimberly A Stephens, Mark W Woolrich, David H Salat
2020 bioRxiv   pre-print
These results demonstrate the potential of our integrated EEG/fMRI analysis for making inferences about neural and vascular processes in higher-level cognitive networks in healthy and at-risk populations  ...  In the default mode network, the HDR pattern in our sample of older adults was associated with a structural surrogate marker of general cerebrovascular deterioration and predicted temporal disruption in  ...  a potential role of such activity states in reducing the cost of brain 7 function during resting state.  ... 
doi:10.1101/2020.05.05.079749 fatcat:3af4lpkngngwlhawcswjxq47bi

Time to wake up: Studying neurovascular coupling and brain-wide circuit function in the un-anesthetized animal [article]

Yu-Rong Gao, Yuncong Ma, Qingguang Zhang, Aaron T Winder, Zhifeng Liang, Lilith Antinori, Patrick J Drew, Nanyin Zhang
2016 bioRxiv   pre-print
Here, we review work showing that neurovascular coupling and brain circuit function in the awake animal are profoundly different from those in the anesthetized state.  ...  While there has been extensive study of neurovascular coupling in anesthetized animal models, anesthesia causes large disruptions of brain metabolism, neural responsiveness and cardiovascular function.  ...  In the resting state, fMRI (termed resting-state fMRI or rsfMRI) measures resting-state functional connectivity (RSFC) between brain regions by quantifying the temporal synchronization of spontaneously  ... 
doi:10.1101/077024 fatcat:brk3y6diibfd7lpycygudr4sl4

BOLD-fMRI in the mouse auditory pathway

Guilherme Blazquez Freches, Cristina Chavarrias, Noam Shemesh
2018 NeuroImage  
Given the importance of the mouse model in plasticity studies, animal models, and optogenetics, and fMRI's potential to map dynamic responses to specific cues, this first fMRI study of the mouse auditory  ...  Indeed, fMRI has been previously used to characterize the auditory pathway in humans and in rats.  ...  Chronic functions in rat brain reveals residual differences that correlate with the differences in regional evoked potentials. Neuroimage 41, 525-534.  ... 
doi:10.1016/j.neuroimage.2017.10.027 pmid:29050909 fatcat:r34y6vj3araz5pllne4f4bhnmq
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