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Low-frequency fluctuations in the cardiac rate as a source of variance in the resting-state fMRI BOLD signal
2007
NeuroImage
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Heart rate fluctuations occur in the low-frequency range (b0.1 Hz) probed in functional magnetic resonance imaging (fMRI) studies of resting-state functional connectivity and most fMRI block paradigms ...
Regressors consisting of cardiac rate timecourses shifted by delays of between 0 and 24 s explained an additional 1% of the BOLD signal variance on average over the whole brain across 9 subjects, a similar ...
Acknowledgments This research was supported by the Intramural Research Program of the National Institute of Neurological Disorders and Stroke, National Institutes of Health. ...
doi:10.1016/j.neuroimage.2007.07.037
pmid:17869543
pmcid:PMC2128785
fatcat:usyjjfajdnfcfomgdxmmgn6nji
Sources of functional magnetic resonance imaging signal fluctuations in the human brain at rest: a 7 T study
2009
Magnetic Resonance Imaging
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We suggest the selection and use of four lagged physiological noise regressors as an effective model to explain the variance related to fluctuations in the rate of respiration volume change and cardiac ...
The following sources of variance were evaluated separately: low frequency drifts due to scanner instability, effects correlated with respiratory and cardiac cycles, effects due to variability in the respiratory ...
Acknowledgments This research was supported by the Intramural Research Program of the National Institutes of Health, National Institutes of Neurological Disorders and Stroke. We thank Alan P. ...
doi:10.1016/j.mri.2009.02.004
pmid:19375260
pmcid:PMC3512098
fatcat:qy76sagjrrffvpl6xxa3777auu
The relationship between BOLD signal and autonomic nervous system functions: implications for processing of "physiological noise"
2011
Magnetic Resonance Imaging
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On the other hand, a different line of work has made important progress in showing that ANS functions such as cardiac pulsation, heart rate variability and breathing rate could be considered as a theoretically ...
brain states as measured in the human brain. ...
This suggests that, when analyzing BOLD signal fluctuations in this frequency band, ANS influences could be considered as a significant source of fluctuations. ...
doi:10.1016/j.mri.2011.03.006
pmid:21543181
fatcat:et3ym6jgb5c3hg77wbvyb6jega
Physiological denoising of BOLD fMRI data using Regressor Interpolation at Progressive Time Delays (RIPTiDe) processing of concurrent fMRI and near-infrared spectroscopy (NIRS)
2012
NeuroImage
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Cardiac noise is particularly problematic, as the low sampling frequency of BOLD fMRI ensures that these effects are aliased in recorded data. ...
Confounding noise in BOLD fMRI data arises primarily from fluctuations in blood flow and oxygenation due to cardiac and respiratory effects, spontaneous low frequency oscillations (LFO) in arterial pressure ...
Acknowledgments This work was supported by the National Institutes of Health, Grant Nos. R21-DA021817 and R21-DA027877. ...
doi:10.1016/j.neuroimage.2012.01.140
pmid:22342801
pmcid:PMC3593078
fatcat:7y24wwlyqvdiplozrsrepqq53i
Impact of physiological noise correction on detecting blood oxygenation level-dependent contrast in the breast
2016
Physics in Medicine and Biology
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the detection of BOLD contrast in the breast in response to a modulated respiratory stimulus. ...
Abstract Physiological fluctuations are expected to be a dominant source of noise in blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) experiments to assess tumour oxygenation and ...
Acknowledgments This work was supported by the NIHR Cambridge Biomedical Research Centre, the Cambridge Experimental Cancer Medicine Centre and the CRUK-EPSRC Cancer Imaging Centre in Cambridge and Manchester ...
doi:10.1088/1361-6560/62/1/127
pmid:27973353
pmcid:PMC6050521
fatcat:obqhatsxljcwbgk5dvaba42afq
Sensitivity of the resting-state haemodynamic response function estimation to autonomic nervous system fluctuations
2016
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
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In this study we compare the resting state hemodynamic response retrieved by means of a point process analysis taking the cardiac fluctuations into account. ...
durations are associated with the mean inter-beat interval and low frequency power of heart rate variability in the brainstem. ...
However, it only filters cyclic effects aliased in the fMRI signal, while the physiology-related low-frequency fluctuations remain in the data. ...
doi:10.1098/rsta.2015.0190
pmid:27044997
pmcid:PMC4822449
fatcat:7qg3fjj3pzcwpj5hgt5772mnxa
Physiological origin of low-frequency drift in blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI)
2009
Magnetic Resonance in Medicine
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Our study supports brain physiology, as opposed to scanner instabilities or cardiac/respiratory pulsations, as the main source of low-frequency drifts in BOLD fMRI. Magn Reson Med 61:819 -827, 2009. ...
We further demonstrated that intrinsic, physiological drift effects are a major component of the spontaneous fluctuations of BOLD fMRI signal within the frequency range of 0.0 -0.1 Hz. ...
BOLD fMRI signals share a metabolic and physiologic source. ...
doi:10.1002/mrm.21902
pmid:19189286
fatcat:qfyg5qrbqng4lg3drj4gzso7ha
Methods for cleaning the BOLD fMRI signal
2017
NeuroImage
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Through the review, we summarize the importance of signal denoising as an essential step in the analysis pipeline of task-based and resting state fMRI studies. ...
This review aims to provide a comprehensive summary of existing methods for cleaning the BOLD fMRI signal. ...
in R & D [SEV-2015-490], and the research and writing of the paper were supported by the NIMH and NINDS Intramural Research Programs (ZICMH002888) of the NIH/HHS. ...
doi:10.1016/j.neuroimage.2016.12.018
pmid:27956209
pmcid:PMC5466511
fatcat:nexqgsdfmvd73grkzcfnrkhesm
Beyond Noise: Using Temporal ICA to Extract Meaningful Information from High-Frequency fMRI Signal Fluctuations during Rest
2013
Frontiers in Human Neuroscience
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Analysis of resting-state networks using fMRI usually ignores high-frequency fluctuations in the BOLD signal -be it because of low TR prohibiting the analysis of fluctuations with frequencies higher than ...
While the standard model of convolving neuronal activity with a hemodynamic response function suggests that the signal of interest in fMRI is characterized by slow fluctuation, it is in fact unclear whether ...
The authors are grateful to Lucie Bartova and Lukas Pezawas for managing the subject recruiting process, and to Georg Rath for technical support. ...
doi:10.3389/fnhum.2013.00168
pmid:23641208
pmcid:PMC3640215
fatcat:ojj5c5ps7rcdblf3vtpid3uywi
The power of spectral density analysis for mapping endogenous BOLD signal fluctuations
2008
Human Brain Mapping
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In conclusion, analysis of PSD is a sensitive method for detecting and characterizing BOLD signal oscillations that can enhance the analysis of network connectivity. ...
FMRI has revealed the presence of correlated low-frequency cerebro-vascular oscillations within functional brain systems, which are thought to reflect an intrinsic feature of large-scale neural activity ...
Acknowledgments We thank the reviewers for their comments. ...
doi:10.1002/hbm.20601
pmid:18454458
pmcid:PMC5441229
fatcat:xqvzeo7warc5nnwyxyo2bhsvau
Investigation of BOLD fMRI resonance frequency shifts and quantitative susceptibility changes at 7 T
2013
Human Brain Mapping
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Although blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) experiments of brain activity generally rely on the magnitude of the signal, they also provide frequency information ...
Keywords BOLD fMRI phase signal changes; BOLD fMRI resonance frequency shifts; BOLD fMRI quantitative susceptibility changes; fractional oxygen saturation ...
Contract grant sponsor: Intramural Research Program of the National Institutes of Health; Contract grant sponsor: National Institute of Neurological Disorders and Stroke. ...
doi:10.1002/hbm.22320
pmid:23897623
pmcid:PMC4280841
fatcat:varkuuodinb4hhtmamsrgkxz2y
Hemodynamic response function in resting brain: disambiguating neural events and autonomic effects
[article]
2015
bioRxiv
pre-print
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Cardiac activity can also induce changes in the BOLD signal, thus affect both the number of these events and the mapping between neural events and BOLD signal, namely the hemodynamic response. ...
To isolate neural activity and autonomic effects, we compare the resting state hemodynamic response retrieved by means of a point process analysis with and without deconvolving the cardiac fluctuations ...
However, it only filters cardiac cyclic effects aliased in the fMRI signal, while the cardiac-related low-frequency fluctuations remain in the data. ...
doi:10.1101/028514
fatcat:pshi5i2nanbklnkn44c55qpp6a
Physiological noise modeling in fMRI based on the pulsatile component of photoplethysmograph
2021
NeuroImage
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Further, we investigate whether variations in the amplitude of the PPG pulses (PPG-Amp) covary with variations in amplitude of pulse-related fMRI fluctuations, as well as with the systemic low frequency ...
The amplitude of the fMRI pulse-related fluctuations did not covary with PPG-Amp; however, PPG-Amp explained significant variance in the GS that was not attributed to variations in heart rate or breathing ...
Overall, the pulsatile component of the PPG signal was found to explain a large fraction of variance in fMRI related to both low-and high-frequency physiological fluctuations. ...
doi:10.1016/j.neuroimage.2021.118467
pmid:34390877
fatcat:s5mtdu7mc5el3f6qxmt3wcsqey
Resting fluctuations in arterial carbon dioxide induce significant low frequency variations in BOLD signal
2004
NeuroImage
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(IT) and the Alberta Heritage Foundation for Medical Research (AHFMR), the Canadian Institutes of Health Research (CIHR) and the Heart and Stroke Foundation of Alberta, NWT and Nunavut. ...
MJP is a CIHR New Investigator and AHFMR Medical Scholar. KI is a AHFMR postdoctoral fellow. ...
A component of the low-frequency fluctuations in the BOLD signal has been ascribed to changes in neuronal activity in functionally connected regions, often termed resting state networks (Biswal et al. ...
doi:10.1016/j.neuroimage.2003.11.025
pmid:15050588
fatcat:p36yzup4rvfgdgpeaahrhtlivy
Low Frequency Systemic Hemodynamic "Noise" in Resting State BOLD fMRI: Characteristics, Causes, Implications, Mitigation Strategies, and Applications
2019
Frontiers in Neuroscience
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Advances in functional magnetic resonance imaging (fMRI) acquisition have improved signal to noise to the point where the physiology of the subject is the dominant noise source in resting state fMRI data ...
Among these systemic, non-neuronal physiological signals, respiration and to some degree cardiac fluctuations can be removed through modeling, or in the case of newer, faster acquisitions such as simultaneous ...
AUTHOR CONTRIBUTIONS All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication. ...
doi:10.3389/fnins.2019.00787
pmid:31474815
pmcid:PMC6702789
fatcat:rup7ygtqava6los7hy2vwyaxaa
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