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Mapping transient hyperventilation induced alterations with estimates of the multi-scale dynamics of BOLD signal

Vesa J. Kiviniemi
2009 Frontiers in Neuroinformatics  
In this study it was hypothesized that the fractal metrics of 1/f BOLD signal trends can map changes related to dynamic, multi-scale alterations in cerebral blood fl ow (CBF) after a transient hyperventilation  ...  In the future, resting-state fMRI combined with fractal metrics of the BOLD signal may be used for analyzing multi-scale alterations of cerebral blood fl ow.  ...  ACKNOWLEDGEMENT Grants #111711 and #123772 from the Finnish Academy, the Finnish Medical Foundation, and the Finnish Neurological Foundation contributed signifi cantly to the study.  ... 
doi:10.3389/neuro.11.018.2009 pmid:19636388 pmcid:PMC2715265 fatcat:y7y7c5lljfcrnardgiivrp246i

Functional imaging of cerebral perfusion

A. Krainik, M. Villien, I. Troprès, A. Attyé, L. Lamalle, J. Bouvier, J. Pietras, S. Grand, J.-F. Le Bas, J. Warnking
2013 Diagnostic and Interventional Imaging  
Downstream from arterial stenosis, this imaging can estimate the vascular reserve and the risk of ischemia in order to adapt the therapeutic strategy.  ...  Perfusion is a dynamic physiological phenomenon able to respond to changes in the homoeostasis of the vascularized organ and the entire body.  ...  We also thank Patrice Jousse for the creation of the figures.  ... 
doi:10.1016/j.diii.2013.08.004 pmid:24011870 fatcat:b4emypfy2nbrpjy3gm5rwihz2m

Cerebrovascular Reactivity Mapping Without Gas Challenges: A Methodological Guide

Joana Pinto, Molly G. Bright, Daniel P. Bulte, Patrícia Figueiredo
2021 Frontiers in Physiology  
Assessment of CVR is usually based on the use of a vasoactive stimulus combined with a CBF measurement technique.  ...  For the vasoactive stimulus, vasodilatory hypercapnia is usually induced through the manipulation of respiratory gases, including the inhalation of increased concentrations of carbon dioxide.  ...  This strategy combines the large dynamic range of changes induced by breathing tasks with the easiness of resting-state methods.  ... 
doi:10.3389/fphys.2020.608475 pmid:33536935 pmcid:PMC7848198 fatcat:4cgdmdj7ijg4tnanrprnq7rb7q

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  
[37] used fMRI to estimate cerebrovascular reactivity by comparing BOLD signal between normal breathing and hyperventilation-elicited hypocapnia (which increases oxygen extraction, induces vasoconstriction  ...  for interpreting BOLD signal changes in the highly dynamic peri-infarct region.  ... 
doi:10.1098/rstb.2015.0353 pmid:27574307 pmcid:PMC5003855 fatcat:qv4wou6p7vdvlolbhdgznpykou

The physics of functional magnetic resonance imaging (fMRI)

Richard B Buxton
2013 Reports on progress in physics (Print)  
An overarching theme is the growing field of quantitative fMRI, in which other MRI methods are combined with BOLD methods and analyzed within a theoretical modeling framework to derive quantitative estimates  ...  Functional magnetic resonance imaging (fMRI) is a methodology for detecting dynamic patterns of activity in the working human brain.  ...  Acknowledgments The author has benefitted from helpful discussions of this material with Nic Blockley, Valerie Griffeth and Aaron Simon.  ... 
doi:10.1088/0034-4885/76/9/096601 pmid:24006360 pmcid:PMC4376284 fatcat:3r24a6k54jcpbkrcpzo62rwl3q

The absolute CBF response to activation is preserved during elevated perfusion: Implications for neurovascular coupling measures

Joseph R. Whittaker, Ian D. Driver, Molly G. Bright, Kevin Murphy
2016 NeuroImage  
A dual-echo pulsed arterial spin labelling (PASL) sequence provided absolute quantification of CBF in baseline and active states as well as relative BOLD signal changes, which were used to estimate CMRO  ...  For the graded visual stimuli, values of n were significantly reduced during hypercapnia induced hyperperfusion.  ...  Acknowledgments This work was funded by the Welcome Trust [WT090199].  ... 
doi:10.1016/j.neuroimage.2015.10.023 pmid:26477657 pmcid:PMC4692513 fatcat:sxhnomblajfofhd2vvs45yduu4

Pitfalls in fMRI

Sven Haller, Andreas J. Bartsch
2009 European Radiology  
Consequently, the term 'fMRI' is often used synonymously with BOLD imaging.  ...  Because interpretations of fMRI brain activation maps often appear intuitive and compelling, the reader might be tempted not to critically question the fundamental processes and assumptions.  ...  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

Cerebrovascular reactivity measured with arterial spin labeling and blood oxygen level dependent techniques

Yongxia Zhou, Zachary B. Rodgers, Anderson H. Kuo
2015 Magnetic Resonance Imaging  
Both CVR quantifications were derived as the ratio of the fractional cerebral blood flow (CBF) or BOLD signal change over the change in end-tidal CO 2 pressure.  ...  A trend toward increased pCASL CVR with age was observed, scaling as 0.64 %/mmHg per decade for GM.  ...  Acknowledgments The data for this paper were acquired at the Bernard and Irene Schwartz Center for Biomedical Imaging in the Department of Radiology at NYU School of Medicine.  ... 
doi:10.1016/j.mri.2015.02.018 pmid:25708263 pmcid:PMC4426232 fatcat:jfey5ak7dfahphmxakhug3yopy

Ridding fMRI data of motion-related influences: Removal of signals with distinct spatial and physical bases in multiecho data

Jonathan D. Power, Mark Plitt, Stephen J. Gotts, Prantik Kundu, Valerie Voon, Peter A. Bandettini, Alex Martin
2018 Proceedings of the National Academy of Sciences of the United States of America  
., and A.M. contributed new reagents/analytic tools; J.D.P. analyzed data; and J.D.P. and A.M. wrote the paper. The authors declare no conflict of interest. This article is a PNAS Direct Submission.  ...  Published under the PNAS license.  ...  This work was supported by the Intramural Research Program, National Institute of Mental Health/NIH (Grants ZIAMH002920 and NCT01031407), and by the Sackler Institute for Developmental Psychobiology (J.D.P  ... 
doi:10.1073/pnas.1720985115 pmid:29440410 pmcid:PMC5834724 fatcat:2kbwfxbd5rfb7o3j3bmclzkklm

Estimating intracranial pressure via low-dimensional models: toward a practical tool for clinical decision support at multi-hour timescales [article]

J.N. Stroh, Tell Bennett, Vitaly Kheyfets, Dave Albers
2020 bioRxiv   pre-print
We compare the performance of these two approaches by evaluating model estimates against observed ICP in the case of a slow hypertensive event from a publically available dataset.  ...  We present model comparisons to highlight the advantages of the incorporated simple model and its possible predictive power with further optimization.  ...  Blue regions outline the raw pulsatile signal, with the red curve identifying the signal smoothed over 2 minute window by a cubic polynomial filter to illustrate the scale of local signal variability.  ... 
doi:10.1101/2020.06.26.174540 fatcat:bp4cadorxrce3drm2evie2qrji

Poster Viewing Session II

2017 Journal of Cerebral Blood Flow and Metabolism  
Conclusions: Hypoperfusion-related changes in the temporal dynamics of the BOLD signal occur due to alterations in LFOs, not cyclical cardiac or respiratory activity.  ...  We investigated the characteristics of these perfusion-related BOLD signal changes in stroke patients.  ...  The following methods were employed for the correction of cross-talk with the I 125 signal: 1) an estimation of the secondary I 123 signal from the primary one given their linear relationship, 2) the use  ... 
doi:10.1177/0271678x17695989 pmid:28366134 pmcid:PMC5441166 fatcat:no54qir44jemni3wacaipk5wxa

What Does Cerebral Oxygenation Tell Us About Central Motor Output? [chapter]

Nicolas Bourdillon, Stphane Perrey
2012 Neuroimaging - Cognitive and Clinical Neuroscience  
To date, several studies have used NIRS to examine alterations in cerebral oxygenation during dynamic exercise, and have found an increase in cerebral oxygenation with medium and high-intensity exercise  ...  Consequently, in subjects exercising at high metabolic rates (elevated oxygen consumption), with hyperventilation, hyper/hypocapnia and high cardiac output, the NIRS signal is rather dependant on systemic  ...  Nevertheless, it is unlikely that even the strongest advocates of the cognitive neuroscience approach would maintain that advances in cognitive theory have kept in step with methods-based developments.  ... 
doi:10.5772/23609 fatcat:mx5sacq5bjetnomh6hlhlib5ja


2010 Cerebrovascular Diseases  
The accuracy of TCD method is enhanced compared to TCCD -combined real-time ultrasound imaging with color coded Doppler signal to display the arterial anatomy and show the flow direction which made the  ...  With the help of today's imaging machinery, dissections can reliably be diagnosed. Their pathogenesis remains obscure.  ...  Different Techniques to Initiate Hyperventilation: Their Effect on Continuous Estimates of Dynamic Cerebral Autoregulation C. Philbey, T. Robinson, R.  ... 
doi:10.1159/000315331 fatcat:hr65yin5bjhedcujexbhd7ygfm

Poster Viewing Session VI

2017 Journal of Cerebral Blood Flow and Metabolism  
Subarachnoid hemorrhage (SAH) induces acute changes in the cerebral microcirculation such as microthrombosis, microvasospasms, and lack of CO 2 reactivity.  ...  Results: In the post-ischemic stroke patients with genotype DD versus genotype II and ID of the ACE gene, the power within a range of alpha -1, alpha -2, beta -1 and beta -2 was statistically lower in  ...  concerted with penetrating arterioles. These coordinated multi-segmental responses require a common signal (i.e. charge) to be shared among neighboring vascular cells.  ... 
doi:10.1177/0271678x17695990 pmid:28366132 pmcid:PMC5441167 fatcat:6z42kszazjdxfgbi5avzlmphdu

ACNP 57th Annual Meeting: Poster Session II

2018 Neuropsychopharmacology  
contextual freezing or in freezing with altered context.  ...  Two weeks post predator stress, we assessed avoidance of trauma cues by measuring exploration of a cue scented with dirty cat litter.  ...  For each task, blood-oxygen-level dependent (BOLD) signals were extracted from each of 378 brain regions derived from a multi-modal parcellation (anatomy, functional MRI, and resting state connectivity  ... 
doi:10.1038/s41386-018-0267-6 fatcat:febeq6uwefgdzm65ccmzrmjwjy
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